new car, short shift, money shift

[Flat6pac]

I got the phone call, Bruce, "Can you fix me up?" did the money shift, 3.2SS.
3 exhaust rockers broke, the heads are in the shop today and I get to critique some one else's work..You can too
Nice job, telling me what cams I m going to be setting up. I thought that was choice way of doing things.
Tube sealant, certainly got carried away with red..don't use it myself but some see the need.
The engine will be here just a few days then back home. Enjoy the pictures
Bruce

[PFM]

Bruce,

Looks to me like a 4 to 3 "upshift" oops not the 4 to 5 he was trying for.... Don't ask how I know....

PFM

[Walt Fricke]

Interesting how those rockers all seemed to break at the adjuster.

Most of mine have broken elsewhere. Often at the shaft area, where things are thin.

I wonder what influences where they break?

[KTL]

What's with the goop around the rocker shaft bores?

[Flat6pac]

I had to peel it out with a scratch all to get the 5mm in to loosen the shafts.
Bruce

[Flat6pac]

Well, yesterday, Monday, the heads are in the shop. Call today and said all 6 exhaust valves are shot, theyre ordered.
I questioned the dilivar studs as the engine has been rebuilt and built. Non magnetic and the gold tone, got to be replaced with steel. The sealing surface is Carrera so there is the torque and 90 degree swing. I took the heads off with a small 3/8 impact so they werent torqued to any more than SC spec.
I have removed the dilivars and cleaned parts trying to get the sealant off..more tomorrow.

Bruce

[Flat6pac]

Mmm, I got the heads back on Monday afternoon, sealed up and bolted to cam carriers, installed the cams, set the valves, installed. I could give it spec torque, 15# +90 degrees swing for the cylinders are Carrera type seal.
The engine is finished, the distributor is now working freely and the vacuum advance is available after disassembly and a lube bath.
Pressure tested the oil cooler, 70PSI 48 hrs
I had to shorten, the new when rebuilt, exhaust studs. There was up to 5 washers on each stud trying to take up the slack. Now all the exhaust is tight without washers.
Cam spec was written down as 2.0 in paint in the chain boxes, the good information. The cams came in at 2.08 and 2.05, I can have that much variance from just looking at the case centerline.
So, It looks like it did when it came in, but itll run...

Bruce

[ninesixfour]

Do you typically just replace the Dilavars and leave the stock steel ones alone? Ever seen a stock steel upper broken?

[Flat6pac]

Ive never seen a top steel broken, always the dilivars. The man from South Africa on here said he broke a new steel stud after he rebuilt but @25ft# torque on an SC I have a hard time seeing it happen.
Then I have a 3.0 that im doing, that I bought core, it has 24 993 studs on it. The only place I have done that is on my 76 930 but that was bought when the 993s were a $ more.
Bruce

[KTL]

Originally Posted by Flat6pac

So, It looks like it did when it came in, but itll run...

No it doesn't. Where's all the illegal use of orange and gray goop? That stuff should only be sold to people with a license to use it PROPERLY. Come to think of it, I really don't know what is a proper use of that crap. RTV is probably mis-used almost as much as WD-40.....

Nice job.

[lindy 911]

Now that we have the internet it's easy to find the proper way of doing things. If it weren't for this site I would have RTV all over my fresh rebuild. A lot of people learned to use RTV as a gasket sealer back in the day. Honda used to promote its use in motorcycle repair and all of us racer types without any money could find almost as many uses for it as duct tape.

I now know the correct use of 574 and Curil-T but lets not get too carried away with bashing those who don't. The fact that motor ran is impressive to me given the builder obviously had limited working experience with a boxer. One of my first posts here was the suggestion to use RTV to seal a chain box cover gasket.

KTL, don't get me wrong as I totally agree with you but the guy deserves a little credit for having the nads to take on a 911 rebuild in the first place. I'm only bringing it up because I'm guilty of it myself like a lot of others here, I'm sure. OK, I'll step down now...

[KTL]

I agree modern times allow us to obtain much more information than years past. But even in the past, parts diagrams were there to tell us what's contained in the assembly of everything. I have Porsche microfiches for my '87 (which of course are no longer used whatsoever, thanks to the magic of pdf PET docs) that I used for years before gettin the electronic info. Granted, I completely understand that Porsche with their part numbers for just about anything is a nice convenience. Many other manufacturers aren't nearly as anal about ID-ing their parts.

Completely agree there are specified uses of liquid gasket. A buddy of mine has tubes and tubes of Mopar RTV that are extras from doing all the gasketing on Jeeps, Dodges, Chryslers, etc. at his Jeep store. So i'm not implying that the use of it is entirely improper. I just don't like it, especially when there's fiber gasket that can be used instead. My thought is that sealant has become a common substitute simply from a cost standpoint. It's easier for a manufacturer to spec a sealant than to have thousands of gaskets cut for their applications. Sealant is great for first-time installation, but when it comes time to go back in there, that stuff is a real PITA to clean up so you can re-seal it again.

Just like anything else, there are going to be shortcuts or misuses. I found on my sump plate someone decided to use 574 in conjunction with the gaskets. If there's a gasket, then there's no need for sealant on top of it! Unless of course someone got lazy and reused the old gaskets.........

Just a pet peeve of mine. RTV works great, especially in a pinch when you just can't get a gasket when you need it. Still don't like cleaning it up....... Chain box sealing wouldn't be the worst application of RTV- if used sparingly. But gooping the stuff on the rocker shaft bores is a hack. I don't think that can be debated IMO. RTV on the cam sealing plate o-rings? That's a hack too.

[lindy 911]

Couldn't agree more.

[Walt Fricke]

Well, I'm less interested in whether something is a hack or not than in whether it works.

Does anyone know if RTV applied onto the ends of rocker shaft bores (carefully cleaned, of course) is going to prevent, or even reduce, the oil seepage out of them?

I have trouble believing it will help, but could easily be wrong there.

I've learned to live with the seepage. I don't like all the grime that gets on surfaces which can help cool the cylinder heads, and it is a PITA to clean off when rebuilding. But I'm not sure there is much practical effect here. Sort of like the irritating little leaks our motors (well, my motors) are prone to.

Walt

[lindy 911]

The folks in the know on this forum hate RTV. But the rocker shafts in the picture above appear dry, not sure if it's the RTV or just a sealing shaft. Personally, I'm willing to use any method that works. Some people thought I was crazy for using JE pistons in my rebuild, so be it. I'm not interested in being a purist, I can't afford it.

I can say that the RSR seals worked for me, some say otherwise.

[Walt Fricke]

The RSR seals have not kept things perfectly dry for me. Perhaps the rockers have just been in and out too often in their cam carriers. Nothing I can't easily live with, though.

[lindy 911]

One thing I noticed during the tear-down was slight marring of the rocker shaft bore. You could not feel the mar with a finger nail but it was visible. I polished the bore and polished the shaft itself, using the RSR seals lubed with silicone grease, re-assembled. It's one of the few places that seals oil that I didn't screw up and is dry. Through bolts, nose bearing o-ring and a few small gaskets ate my lunch for no apparent reason.

[Flat6pac]

When you realize youre torquing steel into aluminum the 9ft# of torque called for is only good new on new. 30 years later and several removals 9# no longer works.
Bruce