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Not everyone has the ability to map their cams and calculate the lift at the different crank positions in software, so here’s a way you can do it at home.
After doing the valve drop as I described above, disassemble the moch up and remove the rod and piston. Re fit the head with the valves installed with soft checking springs. Hardware store will have something. Just strong enough to hold the weight of the valve and retainer. Fit the cam deck, cam and 2 rocker arms, Intake and Exhaust, (set the required lash) time the cam at whatever position you have decided to run it. You can move it as many times as you like to do the same measurement to find the lifts. With the “cam timed”, you may have used your dial indictor to set the cams, so with the indicator in place, position the pointer onto the retainer and make sure it will not be interfered with by the rocker arm and has enough travel. Rotate the crankshaft so the rocker pad is off the ramp and on the backside of the lobe. On the base circle. Zero out the indictor. Remember you timed the cams at overlapping TDC turn the crank backwards well past 20° BTDC and turn the crank clockwise until you reach 20° BTDC. You can also turn the crank all the way around clockwise too, just make sure you know where to stop. At 20° BTDC, measure the indictor travel. Record this number. Do the same at every position through to 20° ATDC. These values need to be less that what you measure doing the valve drop. Plus the clearance you want to run. For example, maybe the valve drop at 20° BTDC was 0.450”. The valve lift at 20° BTDC was measured at 0.490”. Not really but to make the point I’m using these numbers. And you want to run 0.040” piston clearance. Well on paper you have 450” – ( 0.490” +0.040”), which would give you 0.080” interference on paper only. You haven’t crashed the valves into the piston and you have a absolute interference number. Typically the closet the valves will come will be at 10° either side of TDC. You should expect the lift numbers to always be smaller than the valve drop numbers. The clearance can often show up as an issue. Changing the cam timing often is required to obtain the clearance you want or your cutting pockets deeper. You can see now why getting the valve lift numbers from your cam supplier makes it a lot easier. I hope stuff helps and makes it clearer and an idea there are short cuts in doing some of the stuff. When you understand what you are doing and why, its really simple stuff. Hell if I can do it, anyone can. |
I weighed all of my rods, rod caps, bearings, bolts, nuts, pistons and pins to create the most matched sets possible. It's a bit of a (fun) puzzle to mix and match each component to find the optimum balance.
I started with the rods, caps and bearings, and arranged them from lowest to highest. A dry erase marker worked well on the metal pan work surface for writing everything down. http://forums.pelicanparts.com/uploa...1561254394.jpg I then worked through the rest of the components, placing them wherever they would preserve the best equilibrium. Finally, I marked each set with the position it will go in (1-6). http://forums.pelicanparts.com/uploa...1561254394.jpg It helped me to put it all into a quick spreadsheet, to make sure the pairs were as close as possible, and that the heaviest pair would be closest to the flywheel (pair 3-6). http://forums.pelicanparts.com/uploa...1561255002.png I ended up with each pair being matched to within 0.1g (I believe the spec is 0.5g), and the sum of the left side (1-2-3) being equal to the sum of the right side (4-5-6). I'm trusting my machinist's work on balancing each rod itself; everything else he's done has checked out so far. All in all, I think it's pretty well balanced! Next, I went ahead and measured the unstretched length of each rod bolt, and recorded that along with its location (rod 4a,b, etc.). I marked each "stamp" side bolt, so that I'd remember to put it back in the right place. This will allow me to measure the stretch after I've torqued them down, and adjust as necessary. The new bolts were a tight fit, and required some fairly strong whacks to seat in place. I didn't want to damage or mar any of the surfaces, so I found some washers just large enough for the bolts to pass through, and set it up on my vise. The vise is just giving me something to whack against; it's not clamping the bolts. http://forums.pelicanparts.com/uploa...1561254394.jpg http://forums.pelicanparts.com/uploa...1561254394.jpg Next up, I'll assemble the rods onto the crank. - Jake |
@Neil thanks- very nice write up. Makes good sense- at least as I sit now, before actually trying it :)
And: Quote:
Best, Jake |
I'm guessing your machinist also checked the end to end balance as well.:cool:
http://forums.pelicanparts.com/uploa...1561257828.jpg |
@Gordon I think so... Jay at German Precision reconditioned and "balanced" them... I'm assuming that's the same thing as checking the end to end balance... or ?
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So, moving on to the assembly of the rods onto the crank. If you've been following along here, or if you've seen any of the many threads on the subject, you'll know that there is a lot of debate/confusion out there regarding how best to treat your rod bolts; i.e., torque to spec, torque to stretch, how many times they can be stretched, how far to stretch 'em, etc. etc... It's confusing.
The clearest path seems to be to use ARP rod bolts, which have a clear spec for how much to stretch them. For better or worse, I'm using OEM bolts, which don't have a stretch spec, only a torque spec- but then the question is which torque spec to use. Wayne's book says torque to 14.7ft lbs then add 90 degrees, the Woods/Anderson handbook says 40ft lbs, and the tech bulletin for the newer "12.9" bolts says torque to 10.5 ft lbs, + 90 deg, and + 90 deg again. I've also seen 40-55nm, with 55nm being just over 40 ft lbs. Based on some of the great feedback in this thread, I did measure the bolt lengths prior to assembly. My plan is to combine the first two specs, then measure the lengths to compare stretch from bolt to bolt. Then, I'll add torque to any of the bolts that are noticeably shorter than the others. I lubed up the bearings with assembly lube, and applied some of the lube to the threads of each rod bolt. I did not use any thread lock. I started by just finger tightening everything, to make sure that I had everything in the right place, making sure that my rods were in the proper locations, based on the balancing I had previously done, and that each rod bolt was where I wanted it to be, so that I could easily reference its pre-stretch length. In other words, get everything arranged, and double check it, before starting to torque anything. http://forums.pelicanparts.com/uploa...1561581819.jpg Then I went through and tightened everything to 14.7 ft lbs. Made sense to me to do them all in each step, instead of getting to final torque on one and then moving to the next, as this would limit the number of setting and re-setting I'd have to do on my torque wrench. Next, I set my wrench to 40 ft lbs, and started to turn each nut the additional 90 deg. If I hit 40 ft lbs first, I'd stop, and make a mental note of how many degrees short of 90 i was. I found it pretty easy to do both of these steps in a "sweep" kinda way, thus avoiding any issues with standing friction on my torque readings. Turns out, I hit 40 on all of them before getting to 90 degrees, and they were all reasonably close to 45 degrees from the previous (14.7 ft lbs) position. This would indicate that my torque wrench is a little light, and/or that the 14.7+90 spec is intended to get you a little over 40 ft lbs total. From there I measured every bolt and recorded its length into a spreadsheet to easily calculate the stretch. The idea was twofold: make sure that none of the bolts were stretched noticeably more than another (indicating a bad bolt), and to find any under-stretched bolts and torque them a bit more. http://forums.pelicanparts.com/uploa...1561581819.jpg The idea was good, but, in practice, measuring the length of the rod bolts was tough. The OEM bolts aren't designed to be measured like this, so the surfaces of the bolt head and bolt bottom aren't perfectly flat or parallel to each other. This makes it really fiddly to use a micrometer, as you might be on a high spot, for example, which you weren't on during the original measurement. I found that consistency really helped; e.g., I tried to measure each bolt in exactly the same orientation every time. Even then, it was typical for me to see deviations of up to 0.0020" within repeated measurements of the same bolt. This is why the ARP bolts are designed with a little dimple in the head, so that you can use a pointy-tipped stretch gauge and get much more repeatable measurements. My solution was to take 3-4 measurements per bolt and average them together. With that, I was able to calculate the stretch of each bolt. All of my bolts had stretched about 0.0053", with the lowest stretch being only 0.0027" lower than the highest (which is only just over my worst measurement deviation). So, looking pretty good! That said, I decided to try to bring the most under-stretched bolts up closer to the most stretched bolts. I did a rough calculation, based on the thread pitch, to relate the desired additional stretch in length to degrees I'd need to additionally crank the nut. I also added the target measurement, so that I'd know what measurement I was shooting for after applying the additional degrees of turn. You can see those values in my spreadsheet. http://forums.pelicanparts.com/uploa...1561581819.png I then marked my 14mm socket with 2 10-deg markings, at 90 deg intervals. This was not very precise, but would at least give me a visual reference for how far to crank the nut. I'd seat the socket onto the rod nut, find the closest set of markings on my socket, then draw a little line on the rod to align with my first marking. From there it was pretty easy to get down to 5 deg increments, as I could easily eyeball halfway between my marks. http://forums.pelicanparts.com/uploa...1561581819.jpg http://forums.pelicanparts.com/uploa...1561581819.jpg In practice, I found that trying to torque anywhere less than 5 deg didn't work with any reliability; that's just too small to overcome the standing friction with any precision. But, for the bolts which required more than 10 deg, the system worked like a champ! I was able to bring increase the stretch of my shortest bolts to within 0.0011" of the longest ones. Again, this well under my previous measurement's margin of error; so you'd be right if you said this was a bit overkill :) Now that I've gone through all of this, if I had it to do again, I'd probably get the ARP bolts, and do the proper stretch spec. If I were to do the OEM bolts again, I'd definitely measure their lengths pre and post torque, but only with an eye towards catching any obvious outliers. Regarding the different torque specs for the OEM bolts, the experience with my bolts would suggest that it doesn't really matter- they're all very similar to each other. Most of my bolts ended up at somewhere just slightly north of 40 ft lbs (and likely within a margin of error for any typical torque wrench), and also right around 90 deg over the initial 14.7 ft lb torque. Good times! -Jake |
Slightly off topic- but if any of you like this kind of project, and are looking for a semi-professional workspace to work on your own stuff, the shared shop space I work in has an opening. Check out my other post here:
https://forums.pelicanparts.com/off-topic-discussions/1032886-shared-shop-space-available-sf-bay-area.html PM me if you're interested! Jake |
Some slow progress here at the shop.
I cleaned up and test fit the oil pump and IMS assembly: http://forums.pelicanparts.com/uploa...1563218529.jpg ... then I remembered that I did have new IMS gears in my parts box. A quick trip to the hydraulic press and the old gears came right off. http://forums.pelicanparts.com/uploa...1563218529.jpg Here's the assembly with the new gears. Anyone notice what's wrong? http://forums.pelicanparts.com/uploa...1563218529.jpg Yeah, I put the drive gear on backwards! Dumb. No damage though, just a pain to get back off. http://forums.pelicanparts.com/uploa...1563218529.jpg That's better. Ok, everything's as it should be- fits well and turns smoothly. http://forums.pelicanparts.com/uploa...1563218529.jpg The old gears actually look pretty good, after a quick media blast. I'm not going to reuse them, but if I were, I suppose I'd need to somehow polish the teeth (as the new gears appear to be). http://forums.pelicanparts.com/uploa...1563217344.jpg http://forums.pelicanparts.com/uploa...1563217344.jpg Any schools of thought out there on reconditioning/reusing gears like this? I don't need to, but I'm curious... Jake |
I'm getting ready to seal up the case halves, but first, I thought I'd make up a quick set of the metal rod and chain holders:
http://forums.pelicanparts.com/uploa...1563219202.jpg http://forums.pelicanparts.com/uploa...1563219202.jpg http://forums.pelicanparts.com/uploa...1563219202.jpg http://forums.pelicanparts.com/uploa...1563219202.jpg I wouldn't call these professional grade, by any stretch... but they'll do the trick. Jake |
In prepping for closing up the case, I've read a bunch of the threads here about which sealants and techniques to use. The grandaddy of them all is here:
http://forums.pelicanparts.com/911-engine-rebuilding-forum/284737-complete-engine-sealant-thread.html#post2606686 Yes, it's 31 pages (and counting) on sealants. Not because it's such an interesting topic, but because everyone seems to have a different opinion on how to do it! Anyway, I'll be going with a slightly modified/updated version of Henry Schmidt's recommendations: Outer Case Halves: Threebond 1184 (was 1104) Bearing Saddle Surfaces: Loctite 574 (super light coat for sheer strength) #8 Bearing (balancer end) O-Ring: Threebond 1211 (1215 is the new version, but 1211 is still out there) Case Thru Bolts: Dow Corning 111 on Green Viton O-Rings Flywheel Seal: DRY Balancer Seal: DRY Intermediate Shaft Cover to Case: ThreeBond 1211 Oil Breather Cover to Case: ThreeBond 1211 Cylinders to Case: Curil K-2 Cam Towers to Cylinder Heads: Threebond 1184 Cam Chain Housings to Case: Threebond 1184 Cam Chain Housings to Cam Towers: 1184 Cam Chain Housing Cover to Cam Chain Housing: 1184 Gaskets: Thin coat of Loctite 574 I've amassed all of those goops, and more, so I think I'm almost ready. I'm still open to suggestions on the sealant front, however, I definitely don't need to re-hash any of the (religious) arguments from the previous thread ;) http://forums.pelicanparts.com/uploa...1563220452.jpg Having never sealed a 911 case before, I've got a fair bit of anxiety around getting it right; or, at least, as good as it can be. I think part of what makes it nerve-wracking is that you have to move quickly (before the 1184 sets up), and that you probably won't know you've screwed it up until you've got the whole rest of the motor together and driving for a while. The best advice seems to be to stay organized, and to rehearse the routine. A such, I'm double-checking that I have all of the gaskets, hardware, and sealants at the ready. Going through the hardware, I found my original case bolts, bevel washers and nuts. They appear to be in good shape, so I'm inclined to reuse them. I'm tempted to re-plate them, so that they'll look amazing before quickly getting covered in oil because I've botched my sealant job - ha :) On that note, all of my local plating shops have minimum orders, so it doesn't make sense to just send the case bolts and hardware. If I do go down that path, it would be best to send everything I might need re-plated, which means looking into the future a little bit. Any recommendations out there as to what other engine hardware I should send to the platers as a "while I'm there" kinda thing? I already bought a set of new hardware for the engine tin, so I'm mostly asking about structural stuff around the case and top end. Here are some pics of my cleaned up case through-bolts. Fresh out of the parts washer: http://forums.pelicanparts.com/uploa...1563228068.jpg http://forums.pelicanparts.com/uploa...1563228068.jpg http://forums.pelicanparts.com/uploa...1563228068.jpg Hit with a wire brush: http://forums.pelicanparts.com/uploa...1563228068.jpg http://forums.pelicanparts.com/uploa...1563228068.jpg http://forums.pelicanparts.com/uploa...1563228068.jpg http://forums.pelicanparts.com/uploa...1563228068.jpg Jake |
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This is a great thread thanks
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yes very nice thanks
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Has your case really been measured by someone ? I can't believe the main bores are still round , they become oval shaped and when the case is bolted together again the crankshaft will not turn so well . How are the cylinder decks ? #2 is always low on a high mileage engine . The camshaft housing will be warped and the camshaft may bind .
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Put a straight edge on the spigots and using a light from behind you will know right away. Last two mag cases I did still measured out great, but they were low stress T engines not the later heat affected t-reactor 2.7 type.
A tip for good sealing: there are a lot of stud holes as you can see. Make sure there is no debris in them or studs will scrape it off causing it to land on sealant below as you are lowering case half or cam towers. |
I am working on an original '71 with 90,000 miles . #2 cylinder deck was .005" low .
Good luck with your project . |
@1980, @47silver Thanks for the feedback!
@Richey Yes, my machinist (Ted @ German Precision) measured the case. That said, I did not receive a list of those measurements- just the "thumbs up" from a reputable, old-school Porsche guy. He's human, so mistakes are certainly possible- but normally his a-ok is good enough for me. @Richey + @Jeff Can you guys clarify re. the measurements you're talking about? I understand the issue about the roundness of the main bores, and as mentioned, I'm trusting Ted on that one. I do have a bore gauge, so I may try to check it out myself as well; but I think it'll be hard for me to reach the innermost bearings. What exactly do you mean by "cylinder deck"? I'm assuming you mean the surface on the case upon which the cylinder sits? If so, these were resurfaced by Ted (see above re. human infallibility :)) Quote:
Thanks guys! Jake |
Got a bunch of hardware back from the local plating shop, HyTech. They were great; recognized the parts as from a 911 right away. I don't have a lot to compare to, but the quality seems great to my eye. I had my parts back in 3 days. The biggest issue is that they normally do things in bulk, so there are minimum charges per process, which means you have to have enough parts to make it worth it. Also, staying organized is a challenge, as all of the parts get thrown together; so I made sure to take lots of pictures to help me remember which parts go where.
Here's a few pics of the engine through-bolts, you can compare with the pics from the earlier post: http://forums.pelicanparts.com/uploa...1564442395.jpg http://forums.pelicanparts.com/uploa...1564442395.jpg I really like the idea of a DIY plating setup. This thread has been awesome- check it out: https://forums.pelicanparts.com/porsche-911-technical-forum/1023138-zinc-plating-diy.html I may still go the DIY route for future stuff, as I really like the possibility of doing a few parts at a time when you need to. But, despite my workspace being within a semi-pro shop (or maybe because of it...), I have yet to convince my stable mates that having those chemicals laying around here is a good idea... Until then, it's batch 'em up and send them to HyTech. With all the hardware back, it's almost time to seal up the case! Jake |
Ted did my cylinder heads, pretty sure you’ve nothing to worry about in regards to case warp if GP were assessing it.
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If Ted resurfaced the cylinder decks , seems your good to go .
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you could have bought a hardware kit. All the nuts, bolts, washers, etc brand new.
Chris 73 E |
i was not aware of that kit, wished i would have known.
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@Chris Where's the fun in that? ;)
Actually, I did buy a hardware kit, and it has all the basics- washers, lock nuts, etc... but it didn't come with any of the more special bits. The parts that really started me on the plating path were the case through bolts; a new set of those with their washers is around $800 iirc, so cleaning up and re-plating my original ones seemed like a good idea. As the plating shop has a minimum order size, I just threw in a bunch of other hardware. I never really planned on re-plating the easily replaceable stuff- and I like the idea of new hardware, especially for things like lock washers, crush washers and other things like that which may have been overly deformed or stressed over time. To me, it's all a balance... and part of getting that right is learning about the pain and/or expense of the different options. I'm trying to keep this ride mostly original, so I like the idea of reusing as much as I can; but obviously (and to your point) hand cleaning and plating every old washer on the car wouldn't make sense. So, I guess I'm just trying to find the sweet spot between all new stuff and all old stuff! I gather that a lot of the hardware we can buy today, while functionally sound, might not have the same original plating. So for anyone who has to have 100% correct colors for each nut and bolt (and that's not me...) then re-plating is the only option. For example, Jpnovak mentioned in the DIY plating thread that he buys a lot of new bulk hardware in clear zinc for cheap then re-plates it to whatever he wants: Quote:
-Jake |
Finally, I'm ready to seal up the case. I've got all the hardware ready to go, the goops I've chosen to use are ready, and I've run through the procedure a few times to make sure I'm not missing anything. I've got a fair bit of apprehension, having never done this before- but I'm as ready as I can be. Nuthin' to do but go forward!
Here's everything prepped: http://forums.pelicanparts.com/uploa...1564804669.jpg http://forums.pelicanparts.com/uploa...1564804669.jpg http://forums.pelicanparts.com/uploa...1564804669.jpg http://forums.pelicanparts.com/uploa...1564804669.jpg But wait! I had a last minute panic about the oil bypass mod. I'm running a Glenn Yee modified oil pump, which requires the bypass mod. I was pretty sure that I had my case appropriately modded by Ted, but that was a while ago; I had to make sure. That took me down another rabbit hole for a while, but, sure enough my case was good to go. Here's a pic- you can see the new silvery plug, with the smaller passageway just to the side of it: http://forums.pelicanparts.com/uploa...1564805227.jpg Enough distractions, let's do this... I started with the Threebond 1211 on the #8 bearing saddle. This had to be first, so that I could set the crank into the case half. There's a lot of debate on the best way to do this, and certainly more than one way to make it work. I decided to go with Henry Schmidt's recommendation to coat the saddle with finger-wipe of the 1211. Others have gooped the 1211 onto the o-ring itself, while Wayne's book doesn't call for any sealant on the bearing itself (though does recommend Curil around the inner bearing gasket seal). Anyway, I tried to avoid the oil journal while getting thin coat around it. http://forums.pelicanparts.com/uploa...1564805982.jpg Here's the crank, oil pump and ims placed into the case. I checked to make sure that everything was turning freely. I rocked the ims drive gear back and forth to check the backlash, and got a nice clicking sound out of it indicating that it wasn't too tight or too loose. http://forums.pelicanparts.com/uploa...1564807013.jpg My sheet metal pieces worked well to hold the rods, but the piece I made for the chain was pretty flimsy. A few rubber bands helped. http://forums.pelicanparts.com/uploa...1564807013.jpg Next, I'll get the sealant on to the case half and stick 'em together. |
I decided that putting the case sealant on to the left half (not the half mounted to the stand) made more sense, as it's way easier to apply; you don't have to negotiate around all of the studs. Lots of threads on this topic- no obvious downside that I could find.
Also, lots of debate out there about whether or not to put sealant onto the bearing saddles. Factory didn't do it, so that's a strong argument. Also, there's a risk that sealant on the bearing saddles could force the bearing journals out of round, which would be bad... On the other side of the argument is that high performance engines often shuffle-pin the saddles to prevent "chatter", suggesting that adding some shear strength here would be a good thing. Anyway, not saying it's right or wrong, but I decided that a super-thin coat of Loctite 574 on the saddles was a good idea. Personally, I can't see how that would deform my bearing journals into ovals, and if I get some shear strength out of it, then great. So, the 574 goes on first, as it's anaerobic and I don't have to worry about the set up time. Here I'm applying it; keeping it super thin, and wiping away any excess. http://forums.pelicanparts.com/uploa...1564809439.jpg http://forums.pelicanparts.com/uploa...1564809577.jpg Next, I put another skim coat of 1211 on the #8 bearing journal. Then, on to the perimeter, where I used Threebond 1184. I squeezed out a medium sized bead all the way around. Here you can see the 1184 bead in light grey, the 1211 in white, and the 574 in orange (and assembly lube in dark grey). http://forums.pelicanparts.com/uploa...1564810108.jpg At this point the clock is ticking, so I quickly smoothed out the 1184 with my finger. Turns out I had more than enough sealant; as I smoothed it out I ended up removing a fair bit of it. Here it's looking pretty good: http://forums.pelicanparts.com/uploa...1564810528.jpg There were a few spots where I had a lot of spillover, so some quick work with alcohol wipes was required. http://forums.pelicanparts.com/uploa...1564810835.jpg http://forums.pelicanparts.com/uploa...1564810835.jpg Nice! Let's slap it together! |
Lowering the case half with the sealant on it down onto the other half wasn't difficult. I found that practice really helped here (pre-sealant, of course...). I had the timing chain positioned how I wanted it, and knew right where to look for proper alignment. No problems!
http://forums.pelicanparts.com/uploa...1564811874.jpg Here you can see that, even with a little pressure, the case halves don't naturally touch. I think this is because of the o-rings on the oil pump; they need a little force to fully compress into place. Here you can see the gap, before I started to tighten any hardware. http://forums.pelicanparts.com/uploa...1564811874.jpg From here it's just a matter of working quickly to get all the hardware in place and tightened down. I followed the order in Wayne's book, which calls for hand tightening everything first, then torquing the through bolts in an inside-out kinda order, followed by the perimeter bolts. I was sweatin' at this point, not really sure of how much working time I had left- but after double- and triple-checking that I hadn't forgotten any nuts or bolts I called it good. http://forums.pelicanparts.com/uploa...1564813921.jpg Here are some pics of the seam and squeeze out. http://forums.pelicanparts.com/uploa...1564813921.jpg http://forums.pelicanparts.com/uploa...1564813921.jpg http://forums.pelicanparts.com/uploa...1564813921.jpg http://forums.pelicanparts.com/uploa...1564813921.jpg http://forums.pelicanparts.com/uploa...1564813921.jpg I realized that I put the through bolts on "backwards", at least relative to the pics in Wayne's book (he's got the round nuts on the right side of the case). Does this matter? I'm going to re-do them anyway, as I haven't put the green Viton o-rings on yet. My plan was to torque the through bolts, let the sealant set, then go back one by one to remove each bolt and seat the o-rings with some Dow 111. http://forums.pelicanparts.com/uploa...1564814433.jpg Here's a good view of the case seam; alignment looks good, no offset. http://forums.pelicanparts.com/uploa...1564813921.jpg From start to finish, it took me about 3 hours. Back at it tomorrow. -Jake |
Congrats! It's a big step, and a good feeling.
If you're like me your workbench is starting to look a little less cluttered, as a bonus! I decided against 574 on the bearing parting surfaces - very seriously considered it though. If I had done it, I would have used a similar (minimal) amount as you did. Good job all around! |
Way too....oooo much glue!!!!
Some photos show its drained down on the inside of the case. This will end up in the pump and could block some oil passages. If you look how much has oozed out on the outside, the same is probably on the inside. If the parting faces are flat and lapped, you should not even need glue. But we do use glue "just in case". But all you need is a few microns thick. The glue is there to take up any minor divots etc on the parting faces. Once you bolt the two halves together, you squeeze out most of the glue, on the inside as well as the outside. As for the glue on the bearing caps? What leaks are you trying to stop from happening there? The through bolts? This is why there are O rings on the through passages? Don't do it as its un necessary. Advice to many here. Use the whatever glue you choose sparingly. Its about sealing off any chance of leaks. But that is done before any glue is applied. Its done in your prep before you even consider assembly the engine. Adding all this glue is a mind fake, and nothing about making sure no leaks occur. |
@Neil:
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Sounds like you'd vote for redoing it... how big of risk do you think the excess squeeze out inside the case presents? I've read others suggesting that sealant isn't a big threat; if it gets washed off by oil, it'll likely fall to the bottom of the sump, get minced up by the oil pump gears, and/or caught by the oil filter. Maybe the community would benefit from my taking it apart, and taking some pictures to see what the squeeze out inside the case looks like? I'll think on it... Thanks for the feedback, as always. Jake |
I think you can relax.
I used 1184 on my case perimeter a few days ago - I spent a lot of time cleaning my case halves (including removing the studs) and was confident that (as Neil points out) it would seal, theoretically, with no sealant at all. Because of this I used much less 1184 and subsequently have much less squeeze-out than yours, but still don't think you have so much that it's a re-do. Although I wanted to avoid squeeze out, I have no way to confirm on the inside of the case how much there may be, other than to assume it matches the outside. Should you take it apart? I'm not so sure. Maybe wait a few days and get a feeling for how strong the sealant is? I get the feeling it's pretty tough, and not going to go anywhere. It IS supposed to be resistant to oil so honestly I don't think you have to worry. I'll have a look tomorrow and give you my thoughts, after it's had a few days to cure. I can't remember when it reaches full strength but that information is on the threebond website. Even if a piece of the squeeze-out ended up in the bottom of the case and got through the screen, it would end up going through the filter, anyway. |
Thanks, @Jonny. I'm really on the fence about it. I had a pro mechanic look at it today (not a Porsche guy, though...) and he said don't worry about it.
I'm also quite cognizant of being that guy who asks for advice then ignores it ;) I hate it when people do that to me! Anyway, still stewing on it... Jake |
F' it, let's crack this sucker back open! A little extra work to settle some doubt can't hurt...
First step, loosen all the bolts. Interestingly, I noticed a fair bit of shrapnel as I removed the through bolts. http://forums.pelicanparts.com/uploa...1564978552.jpg http://forums.pelicanparts.com/uploa...1564978552.jpg Upon closer look, it appears to be the fresh plating scraping off of my through-bolt washers. A little disconcerting, but as long as it all stays outside the case it oughtta be ok. I'll make sure to clean these bolts thoroughly before reinstalling. A few whacks and it's coming apart. http://forums.pelicanparts.com/uploa...1564978552.jpg http://forums.pelicanparts.com/uploa...1564978552.jpg The 1184 around the perimeter clearly hadn't cured all the way (it's been about 48 hours). Not sure if this will make the clean up easier or harder, but no turning back now. Ok, case half removed, let's take a look: http://forums.pelicanparts.com/uploa...1564979046.jpg http://forums.pelicanparts.com/uploa...1564979046.jpg http://forums.pelicanparts.com/uploa...1564979046.jpg http://forums.pelicanparts.com/uploa...1564979046.jpg Looks like I has a little heavy with the sealant, but nothing too crazy. There are a couple of big-ish globs in there. http://forums.pelicanparts.com/uploa...1564979046.jpg http://forums.pelicanparts.com/uploa...1564979046.jpg But wait! I did find an issue... |
Here's a problem:
http://forums.pelicanparts.com/uploa...1564980532.jpg I forgot to bend the locking washers into place around the oil pump! So, even if I didn't really need to re-split the case for the excess sealant, I'm glad I did. Here are some more pics of the sealants, for the archives: http://forums.pelicanparts.com/uploa...1564980700.jpg http://forums.pelicanparts.com/uploa...1564980700.jpg http://forums.pelicanparts.com/uploa...1564980700.jpg http://forums.pelicanparts.com/uploa...1564980700.jpg http://forums.pelicanparts.com/uploa...1564980700.jpg ...and some looks at the 1211 around the #8 bearing: http://forums.pelicanparts.com/uploa...1564980832.jpg http://forums.pelicanparts.com/uploa...1564980832.jpg http://forums.pelicanparts.com/uploa...1564980832.jpg All in all, I gotta believe the sealants woulda been ok. That said, I'll definitely go lighter next time around. Hopefully this will help some of y'all in the future! Now I've got some more cleaning to look forward to. - Jake |
Good job. Proud of you for taking the time to do this. Its easy for others to say it would be ok, but you are the one that has to live with mind "f..ing" yourself, will it be ok.
In my opinion, it would not have been. You do not need any piece of the sealant to clog any oil galley. You hope it all gets caught in the filter. This time apply the sealant microns thick, not inches. Do not put anything on the main webs. leave them dry. Just make sure the parting faces are flat, no divots and if in doubt, now is the time to remove the perimeter studs and lap the faces. Remove the tabs that hold the oil pump nuts too. Yes, remove them. Make sure the threads on the studs are in good condition and the nuts are good or new. If you like, put a tiny bit of red loctite on the threads. Then torque the nuts to 18 ft/lbs. They will not come loose. We never use those tab thing'ys. If you think about it, the nuts holding the rod bolts tight are under more stress than the oil pump nuts. Make sure when you install the pump again that after torqueing down the nuts the coupler shaft is free to move back and forth. If not reposition the pump and try again. Go slow and be methodical. Ask if you are not sure. Great job. We have a saying here at my business. If something makes you uncomfortable and continues to do so, regarding any sort of assembly procedure, it will almost always rear its ugly head and bite you hard. There is no place in this business for risk taking. Its either right or wrong. |
Very interesting - thanks for sharing the pics!
Like Neil said, great job - what better way to insure you're getting the results you want, than going back and checking like that. You've learned more that 100 hours of reading forum posts, and able to get real feedback on your process, with your own eyes. So, time well spent. In my opinion the 1184 would have been alright, PROBABLY..... one or two blobs look threatening. Interesting how much thickness remains in places of the parting surfaces of the case, where other places it's squeezed out completely - the mag cases obviously need the sealant a lot more than the aluminum ones. The 1211 looks like it was a bit much, with the squeeze-out to the inside of #8 - I went lighter and concentrate it to the outside. The 574 still leaves me conflicted. It looks like it squeezed out well enough that main clearances wouldn't have been affected (much"), are you able to judge that at all? Opinion seems to be split, even among experienced builders. The factory says "no".... If I had a mag case motor I'd be tempted. |
You have the case thru bolts installed correctly, they come in from the 4-5-6 side. There is a slight difference in the case hole diameter to account for the o ring on the shoulder of the thru bolt versus the o ring on the nut end is on a narrower diameter of the bolt. Every picture in the shop manual shows this direction.
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Thanks, all.
@Neil Your comments are much appreciated. It was a pretty easy decision; though I'd lose some momentum, the time to re-open the case is peanuts relative to the total amount of time that I'll have in this project. The old line "If there is any doubt, then there is no doubt" held true here. In my professional life we'd call this technical debt; you might not have to pay today, but you will have to pay... plus a lotta interest! Good tip on the oil pump locking tabs. @Jonny: Quote:
Good idea re. the 1211; I'll go lighter and pull it more away from the inside. I'm still conflicted on the 574 for the main bearing saddles. I hear Neil saying I don't need it (reinforced by the factory practice of leaving them dry), countered by Henry Schmidt's recommendation to do it as a "why not" kinda protection. In my own mind it's hard for me to see a downside (assuming an ultra-thin coat). To your question, no- I can't really judge if my application of the 574 would have changed any of the clearances. I can say that, while cleaning everything up, in a few places I was able to peel off a translucent "skin" of dried 574. Really tough to know if this was because the 574 didn't squeeze out and created a tiny gap (bad), or if there already was a tiny clearance between the bearing saddle surfaces which the 574 then filled (better). Still thinking on it. @Ed: Thanks! I should have referenced the shop manuals before asking. For whatever reason I'm always slow do dig into the manuals (probably because I have them as PDFs, and they're hard to search...). Here's a pic, which confirms what you're saying: http://forums.pelicanparts.com/uploa...1565120107.jpg ...and the pic from Wayne's book which mislead me! http://forums.pelicanparts.com/uploa...1565120454.jpg Anyway, as someone wise said somewhere in this forum, Wayne's book is a great book, but it's not the only book... |
Here I'm cleaning up the case (again). A combination of acetone and mechanical scraping seemed to yield the best results (though I don't think there's any getting around this job being a PITA). The acetone did best where the sealant was still clearly uncured. I tried to carefully use a razor blade in a few spots, which worked well, but I noticed that it was too easy for me to potentially scratch the case, so I stuck to plastic scrapers.
I will say that the big globs of squeezed-out sealant that I had on the inside of the case were NOT easy to remove. It's hard for me to imagine those things somehow coming loose and then interfering with the oil system... but, still better to have none at all! http://forums.pelicanparts.com/uploa...1565121449.jpg http://forums.pelicanparts.com/uploa...1565121449.jpg http://forums.pelicanparts.com/uploa...1565121449.jpg Jake |
Quote:
Anyone know if this makes any real world difference on a late model case? I've got mine installed according to Wayne's Book......... Just installed my cylinders last night. &^%^&$$. |
Glad you made the move to open it back up and re-seal. The #1 bearing looks like it received a fare amount of sealant in the oil groove.
http://forums.pelicanparts.com/uploa...1565185935.jpg |
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