Agree with Walt on the above. The 3.0 and 3.2 cases have proven to be very stout and pretty much never need line/align boring thru the mains.

That ebay link above is by a guy here on the forums. His name is Ed Baus (edbaus username) and he is a stand up guy. He's not selling crap that other people are going to get screwed on.

I think if you've got the wherewithall (sp?) to rebuild the engine, then a replacement case will get you pointed in the right direction. WAY cheaper than a complete engine. Plus, you NEVER know what surprises lurk inside an alleged "good, used" engine that someone is selling. Even a reputable seller can only know so much about an engine he is selling secondhand.

Thanks Kevin,

The search continues. Walt mentioned Ollies nearby, I know there is an Ollies in AZ. but also one in California. Are they affiliated? The AZ Ollies is also a Porsche specialist Machine Shop...

Another photo showing the worst of the past machining damage....:mad:http://forums.pelicanparts.com/uploa...1361487527.jpg

I believe Ollie emigrated from CA to AZ. Their loss, your gain.

I just got off the phone with a guy who says that while 10 years ago the "aluminum cases never need align boring" rule was more or less correct, they have had 10 more years of use, some of them hard (as in racing) use. He believes he can tell if this is needed by looking at the wear patterns on the main bearings.

You might consider sending a used case you purchase - even from a trusted source like Ed Baus - to Ollies to have them measure it and tell you if anything needs to be done. If Ed has a good history of this case, and it came from a street car, and had never blown up, and sat on a shelf for 10 years as a bare case, and so on - maybe having it checked is overkill. Maybe any good machine shop could check, but it takes more than just a bore gauge, as you are not only checking the bearing bores for ovality, but are really checking to see that each bore is absolutely concentric with all the rest. A place like Ollies is used to doing just that on those cases.

Me, I think I'd skip that step. But that's just my Alfred E. Neuman side.

Alfred -

That's the first piece of good news I have heard since the first bolt was loosened (Ollies local that is).

I believe I will be hauling my heads, replacement case and anything else (crank shaft? rockers? etc.) over to Ollies once I find a case I can live with. Any suggestions of what other parts to have checked and/or machined, well, I am all ears. The last thing I want to do after going through what I have so far, is do it again. I will admit though, that if it wasn't for the $, this process would be almost a pleasure for an old engineer like me.

Who was it that said: "This is the most fun I ever had without actually having any"

Thanks as always Walt!

Doesn't hurt to have a crankshaft checked to be sure it is straight. Check the journals to see if you can still use standard ID bearings (I think maybe 1st under rod bearings are less expensive than stnadard these days? So having crank ground if it needs it maybe not all bad). Have journals polished. Have rods checked and resized if needed, plus wrist pin bushings checked and rebushed as needed. Rockers can be checked, resurfaced, and rebushed as needed. Have them check pistons (including ring grooves) and cylinders (ovality).

Not mentioned is the matter of the cylinder and piston type you have - the desireable Nikasil, or the less desireable Alusil. There is a whole evening's Pelican searching's worth to get an idea what that is all about.

I'd guess that most of the parts - crank, rods, pistons, flywheel, pressure plate - which need balancing are still reasonably in balance for a street motor, where you won't run it up over 6,250 or so (and that not often) because your optimum shift point won't be higher than that anyway.

But that is one of those while I am doing this things to ponder once you learn what you are spending and what the extras might cost.

Well..... here's a wrinkle..

I contacted the boys at Ollie's and sent along the same pictures I previously posted on this forum. They say that they have seen AND REPAIRED worse than that on MAGNESIUM cases!

While they will reserve final judgement until they have the case in their hands, they are quite optimistic that they can give me my case back as good or better than new. They also mentioned that if needed, they can re-drill the threads a couple of thousandths outside away from the cylinders and that once the studs are flexed a bit to clear the threads, the heads will slide on fine.

So... original case (devil I know) back for a few hundred bucks vs. continuing my search for a more expensive and potentially iffy replacement...... I am thinking of driving everything over to Ollie's next week unless someone can chime in here!

Thoughts?

Gee, and just when things were going so well....

so, in addition to the case repair/replace question (see previous post), I should now beware of the dreaded Alusil P&C's? Like the case, I was planning on taking them over to Ollie's for a check (honing?) before re-ringing. One of the rings was found to have a tear in it on inspection, and though my pre teardown leak downs showed all cylinders at 2% or lower, I thought it was prudent to replace them all.

I still have to verify that mine are Alusils (10 fins vs. 11 for Nikasils?), before I add this new fish to fry, but as I am finding out, luck is not exactly on my side so far!

Anyone?.... Bueller?

Contact me if you are considering a used SC crankcase.

I have several available.

Alusil vs Nikasil easy to differentiate. The Nikasils are magnetic on the inside surface. Not strongly, but demonstrably.

Alusils not. The Alusil pistons have some sort of ferrous coating, too, per what I have read, so perhaps the piston sides are magnetic? I've got some Alusil pistons in my basement, and maybe I'll check them.

If you had 2% leakdown, perhaps you just save $ and put them all back in as you found them. Perhaps replace just that one ring. As you have noted, one of the strategies for Alusils is to do just that. 2% is about as good as it gets.

I once had a mag case welded up. It has suffered a whole lot more damage (engine blowed up, as they say) than this little stuff on your case. Worked fine, though other issues caused me to replace it.

I know Ollies says it has been able to do extensive welding successfully on the early sand cast aluminum cases - they can even cut out a damaged section, and weld in a replacement harvested from a similar case which was damaged somewhere else (blowed up motors often have a slot from a spigot all the way up to the case parting line cut in by an errant connecting rod).

I have a sand cast case which was created by mating two unmatched case halves and doing suitable machining to make this work. It has a couple of places where some welding was done (nothing really dramatic, though) to repair miscellaneous damage. Worked fine for the previous owner as a 2.8 race motor, and has for me too.

I have no personal experience with welding the later style pressure cast aluminum cases. And claim no expertise with the effects of welding on aluminum, far less how important this might be in particular parts of a case (some must be more critical than others).

Crazy...

As adamant as Ollie's is about being able to fix my case (based on the photos only), there are those who are just as sure that it's a bad idea...

On the pistons, based solely on the leakdown numbers and NO smoke, I am leaning toward using what I have as long as Ollie's checks and gives the thumbs up on all tolerances. I will most likely replace only those rings that are damaged (so far just the one) and move on. Of course, I am only assuming (based on my current luck) that mine are A-loser-sil;) at this time. I may also entertain changing them if I can find a good used replacement Nikasil set (looking as we speak).

Also, while I imagine that true engine combustion is at higher pressure than a leakdown test produces, how is it that the bad ring did not reveal itself with my 2% numbers???

like I said, crazy..

Another indicator of cylinder/piston type is the name on the cylinders. Almost all Mahle are Nikasil. Only very rarely were there Alusil cylinders made by Mahle. So if your cyls don't say Mahle, they're definitely Alusil.

Also, you can have Alusil cylinders bored and plated to your desired spec with Nikasil.

But if you're planning on reusing your rings, you can just stick the pistons back in their respective cylinders and you're good to go. By the way, which ring do you have to replace? Is it one of the two upper compression rings or the lower oil control ring?

Agreed it's good to check the crank for straightness and see if it's still in spec. The bearings themselves can give you an indication of what kind of wear the crank has seen. But it's still prudent to check because, obviously, you never know what decisions the previous wrencher made. Often times the crank can just be flushed out with solvent and put back in as-is, so long as the journals look good and measure within spec.

Appreciate the response Kevin. Turns out my rings were fine after all... I misunderstood the info I received and it was only the seal between the head and spigot that was "torn". I am happy to play the fool on this one! :D

Now I am back to seriously considering running what I have, after all, the thing was re-ringed 35k miles ago and all cylinders are at 2% or less leakdowns.

I have the rockers and camshafts on my mind now. Pretty sloppy shaft/bushing interface and no record of any work being done on them with the previous re-build.
Faces look pretty good and the shafts also show little or no obvious wear.

I want to at least send them out for re-bushing. Is it also a must to re-face them and if so, re-face the cam lobes as well? Lastly, for any and all this work, who might out there recommend to do the work. Anyone out there with a core exchange program? what kind of pricing might I be looking at?

Thanks again for the interest and all of the great responses SmileWavy

Bill

Yes those cylinder shims are typically a discard item when you rebuild the engine. Often you'll have to adjust your shim thickness choice from what was original, if you had work done on the cylinder head surfaces. The shim thickness is what sets the final deck height.

I'd go with what you have if it was recently re-ringed and has good leakdown numbers. How were the compression numbers, if a compression test was done?

Rocker bushings seem to be an increasingly common wear item. Take a close look at the bushings inside the rocker to see if they're really worn. Shafts also help you determine wear by the fingernail test. If you can feel any ridges, they are worn. The wear spec on the shaft is VERY tight. So only the slightly worn shafts can be polished and re-used.

There are quite a few shops that do the rocker work in no particular order

Supertec (Henry Schmidt here on the forums)
Steve @ Rennsport Systems (Steve@Rennsport here on the forums)
John Dougherty at DR Camshafts (camgrinder here on the forums)
WebCam- webcamshafts.com
Elgin Cams-
Craig & Denny at G2 Performance (cgarr here on the forums)

Any time you rebush the rockers you must square up the rocker contact pad. Kicker is that reconditioned rockers are all nice & new, but your cams are not if you haven't reground them or bought new. So sometimes you're better off sticking with what you've got if the wear is not bad. Existing rockers and cams have worn-in and fit nicely with each other. That's why its advisable to keep your rockers labeled where they came from upon disassembly.

Great info. Kevin,

No compression test was done, just L.D.

With regard to the shafts you mention. I assume you are talking about the rocker shafts and not the cam shafts? I suppose I was considering the 180 degree turn technique as they seem in reasonable condition.... No?

As far as the Machinist you mentioned, I contacted John already. Seems like a good, qualified guy. I am committed to re-bushing and re-facing the rockers, and the decision I have to make now is should I get the cams done while I am at it. They look pretty good, but am I taking a risk? John believes that with my 9.3-1 comp. ratio, it is a worthwhile upgrade to move to a 964 profile. He also has a less aggressive profile as well. The car will be street (with a track wannabe personality), so I want a set-up that will be long-lived and reliable.

Thoughts?

Thanks allot for sticking with me here...

Bill

Flipping the rocker shafts is indeed acceptable practice! The shafts used to be cheap and was easier to just buy new vs. polish/recondition. Now the shafts are $20 each....

Well if you're going to do the rocker reconditioning, you should have your cams reground to have both working on each other's fresh surfaces. Just doing the rockers alone is similar to replacing chains w/out doing sprockets- accelerates wear on the new chains.

As long as you are doing a cam grind, yes the 964 is a worthwhile change. No ill effects with the 964 profile. It's a common modification that the tuners discovered works quite well years ago.

Thanks again Kevin,

964 it is. Already have the SSI's, B.B muffler, cat-delete tip and an Electromotive HPV-1 on the thing so.....

Just had a sit down with the Machine shop on my heads. While he will measure everything out, he thinks they look pretty good (they were re-done 35k mi ago).
The mystery on them is that there seemed to be a bit much build-up which would seem to indicate an oil-burner. This was not the case while it was running although several of the exhaust valve seals were "torn" as opposed to dis-integrated. The guides look just a bit long, but upon measuring, do not look to be the culprit as far as interfering with the seals. Springs look good too but will be tested.

Current theory on the ripped seals is that they were not properly fitted when installed during last head job and got banged around at first? Anyway, this may or may not explain the excess oil buildup around the valve seats. I guess we will know more once the heads are disassembled and measured.

Speaking of valve seals... I am being told that I should look for the Viton seals instead of the teflon type????

Much appreciated,
Bill

What color are the valve stem seals? The white are teflon and some have said they seal too well and don't allow lubrication of the guide. Also seem to be a bit harder to install. So that may be why yours are damaged- faulty install method.

The Viton ones seem to be the preferred type. Do a search and you'll see varying experiences

http://forums.pelicanparts.com/911-engine-rebuilding-forum/528811-valve-stem-seal-teflon-og-rubber-viton.html

Show us a picture of the oil buildup. Could be valve guide leakage or could be carbon buildup. Carbon buildup is fuel related and often occurs on engines that are "babied." Need to keep port velocities up and blow that stuff out. Engines that are rarely taken to high rpms often have a considerable amount of carbon on the exhaust valves. That said, often times the super duper carbon buildup in the exhaust guide(s) is a combo of valve guide leakage and fuel.

So that's what they mean by "spirited" driving ehh?

Heads are at Machine shop right now for disassembley and measuring. The seals are the white teflons. I have read more than my feeble mind can handle on the teflon/viton debate but it does seem that the prevailing wisdom out there (as well as my machinist) is that Viton is preferred these days.

I am posting the photos I have at this time that might give you an indication of the buildup issue. The fuel theory is interesting.... I know that the car had an un-diagnosed blown airbox and had been running quite rich for a while before we got in there so there's that too...

Not sure if things are clear enough but here goes -
http://forums.pelicanparts.com/uploa...1362000622.jpg
http://forums.pelicanparts.com/uploa...1362000665.jpg
http://forums.pelicanparts.com/uploa...1362000719.jpg

How do the exhaust valves look on the inside as they currently sit in the head's exhaust port (where you bolt on the heat exchanger)? That's where a lot of carbon buildup occurs- on the end of the valve guide sticking into the exhaust port.

I recently got a set of pistons and cylinders from an '85 3.2 that were said to have only 16K miles on it. 16K seemed reasonable based on how nice the cylinders looked. But I was surprised how much carbon was on the piston tops. Also found that at some point early in the carbon buildup process that someone slightly over-revved the engine because the pistons all had tiny little smiles on them where the exhaust valves had contacted the pistons....... :mad: But nothing a little bit of grinding and mirror polishing couldn't fix.

They actually looked quite nice, clean and shiny (at least on the ones we looked at yesterday).

So by the photos, does this look like carbon buildup (fuel) as opposed to oil?

Also, as I am considering re-using my P&C's as they are, am I foolish not to clean all that crap up and if so, how best do it. Everyone warns about messing with the Alusils once they seat :confused:

By the way.... you want to part with those 3.2's ? :)