Help: REbuild is leaking oil like crazy - Page 3

Porsche_monkey · 04-30-2004, 03:44 AM

Yes John wins. Dirko rules, huh?

Porschephd · 04-30-2004, 07:24 PM

Not that I have had any issues with 574 (hope I never do) but I have a rule of thumb. I set all my bearings, check all the orings, dowels, etc and regroup. I then apply my 574 when I am ready to put the case halves together-NOW. I never let them sit longer then smearing the 574 with my finger and slapping them together. I do see guys having issues with them when they let sit, even for 10-15 minutes. While it is not supposed to make a difference, I believe you can not let it skin. At any rate I just make sure it is a smear and go.

Wayne 962 · Wayne 962's Garage

Don't know if I buy that. The 574 shouldn't harden - only in the absence of air. Theoretically. I've seen squeeze-out that never hardens. Still 45 minutes tops is what everyone seems to use as the benchmark for assembling the case halves...

-Wayne

dtw · 05-02-2004, 09:07 PM

It skins like gravy if you don't assemble it quickly. Good to have all components ready to go as soon as the orange goop is spread. It doesn't harden up, it just skins.

Porschephd · 05-02-2004, 09:10 PM

In theory it should not dry until it is without air, however I have heard of way to many people having issues with letting the 574 sit. I can say that I have seen it skin when blobbed on the surface and left. I believe it is the skinning in conjunction with the amount. If used with a roller I doubt there to be an issue, however with a smear and glob from your finger the amount is far greater and one small spot would cause a mess. There are a few examples on this board as well as John. For me, I can't risk it. Not with the warranty I offer. 574 and put that case together.

ChrisBennet · ChrisBennet's Garage

Steve Weiner told me that the trick is to snug down the perimeter bolts first. I see Greg Brown also says the same thing. Greg Brown wrote a good article (does he write any other kind?) about case sealing in Velocity Winter 2002 starting on page 24*. Thanks to Bill V. for tipping me off to this article.
-Chris

* Page 24 of the PDF, page 46 in the hard copy magazine.

Porschephd · 05-03-2004, 06:05 AM

That is always a great idea and I do agree. The ONLY time I DON'T is when it is an old 2.7 case.

Wayne 962 · Wayne 962's Garage

This is another topic up for interpretation. On the subject of 574, I think that it gets blamed quite often as a material defect, when in fact, the problems are with long install times and/or poor surface preparation. I know that on at least one motor, I was guilty of not preping the surface well enough, and it did begin to leak there.

As for tightening the bolts - Stephen has it right - the early mag cases are a problem, and tweak and torque themselves. I would say on the aluminum cases (stiff) that it wouldn't terribly matter which order you torqued the nuts down, but on the mag cases (especially ones that haven't been machined fully/properly), I would torque down the through bolts first...

-Wayne

Nitrometano · Nitrometano's Garage

May the engine need a Kotex!!!

mtelliott · 06-25-2004, 06:00 AM

As a quick update, I've got the engine case, all sealed up and just getting ready to install the exhaust and intake? Might actually be able to get it in the car over the holiday (July 4th) and see if I did a better job this time round.

As for cleaning the cases, I was meticulous this time round. Made sure ti really wipe everthing down and applied plenty of 574. Reinspected the case (with another set of eyes examining and found a piece of the spreader brush). Did a double examination of the case to make sure it would go together cleanly, then put it all together and tightened it down quickly and efficiently (that's what I think I did wrong the first time round).

In case your wondering why it's taken so long, I have a two year old (who likes to help) and a 4 month old (and a wife that puts up with my obsession).

Michael

Porsche_monkey · 06-27-2004, 02:27 PM

My suggestion is to use plastic spreaders from a hobby shop, not the cheesy little brushes that leave hairs behind.

mtelliott · 07-19-2004, 06:35 AM

Update: She's Alive, alive I tell you, alive.

Fired her up this weekend. After about 10 seconds of cranking, she fired right up. Idle went to about 1800 then settled down to around 1000 RPMs. Talk about a relief.

And then, I notice a leak. I'm thinking, oh *&$%. Went back and looked at where it was coming from and thought, well that's strange, it's coming out of the passenger side heads. That can't be right.

Walked away, and then came back. Looked closer, and noticed that it was coming out of the oil fitting on the chain tensioner on the passenger side. I remembered that in Wayne's book, he mentions not to over tighten since you can always tighten if they are leaking. Picked up the wrench, gave it a little snug, no more oil. When it was leaking, it fell down on the metal surround and leaked everywhere through it. Now, it appears that I have a leak proof engine.

Talk about relief.

Then I noticed the fuel leak. The rubber line running from the engine to the hard line that I believe runs back to the tank was leaking. Reached in there, tightened it up, still leaks. Tightened it up a little more, still leaks. So, I'm thinking that a 22 year old line has the right to leak and I'm not going to question it (I think the fitting on the inside is turning as I turn the nut on the hard line).

Any way, It would appear that the reason why the engine leaked the first time was that I didn't get the cases put together quickly enough.

Many thanks to a lot of members of the board.

Wayne: Your book is excellent. Had I followed your advice without question, I probably would have not had to do it twice.
Others: Thank you for your advice, your tools, your opinions, and your support. This was something that I always wanted to do and am much richer (poorer actually) for the experience. Of course, I'm already thinking a couple years down the road when I build my race car. Going to wait till my kids get a little older so that they can be involved.

ChrisBennet · ChrisBennet's Garage

Quote:

Originally posted by mtelliott
Then I noticed the fuel leak. The rubber line running from the engine to the hard line that I believe runs back to the tank was leaking. Reached in there, tightened it up, still leaks. Tightened it up a little more, still leaks. So, I'm thinking that a 22 year old line has the right to leak and I'm not going to question it (I think the fitting on the inside is turning as I turn the nut on the hard line).

Congrats on your engine rebuild. I might suggest that you use a 2nd wrench to counter hold when tightening any sort of fitting.
-Chris

mtelliott · 07-19-2004, 07:27 AM

There's no way to counterhold on that line. Not that I know of. It's called the fuel return line. It's a rubber hose that doesn't have a nut to hold onto. It's hard for me to explain. I can put my hand on the line and it doesn't turn when I turn the nut on the hard line that connects to it, but I can't get it to stop leaking.

john walker's workshop · 07-19-2004, 09:11 AM

use a 11mm open end wrench to counter-hold the return line. there are flat sides on the metal end that attaches to the engine line.

mtelliott · 07-19-2004, 08:33 PM

John,

You are the man. Worked like a charm. Took a little less than 1/8 turn to seal it. No gas leaks. Took my car for it's first spin. I purchased it in boxes so this was the first time I've ever driven it.

Thank you to you, Wayne, Henry, Grady, and quite a few others for all your advice.

I'm having a good day.

Michael

Henry Schmidt · Henry Schmidt's Garage

Quote:

Originally posted by snowman
If this were a chevy you wouldn't have this problem.

That's right. "if it were a Chevy you wouldn't have this problem". But then again if it was a frog you wouldn't have to feed it gasoline. My point, a frog is not a car and a Chevy is not a Porsche. I would rather eat sand than give up my Porsche to drive a Chevy, any Chevy.
That said, I do own a Corvette but if I had to choose, the Vette is gone.

Back to the real question: We always use 5 different adhesives when assembling 911 engines.No one adhesive can perform all the needed sealing requirements. ThreeBond 1104 on case halves, ThreeBond 1211 on the # 8 main bearing, Curil T on the cylinder base geskets, 574 Loctite where the case halve comes together at the through bolts and on gaskets (very this coat) and Epoxy patch where epoxy is required.

82SC · 07-27-2004, 10:30 AM

this may be a dumb question but could someone, post rebuild use the case breather hose and pressurize the case to see if there are any obvious leaks?

Problems with this that immediately come to mind is that the case is not heated so it may not reveal all leaks

I guess one would have to plug up all oil lines...and I would guess that leaks by the cylinders would be minimal...

hmmmmmmmmmmmm

82SC · 08-03-2004, 02:03 PM

anyone...

mtelliott · 01:32 PM

Quote:

Originally posted by 82SC
this may be a dumb question but could someone, post rebuild use the case breather hose and pressurize the case to see if there are any obvious leaks?

Problems with this that immediately come to mind is that the case is not heated so it may not reveal all leaks

I guess one would have to plug up all oil lines...and I would guess that leaks by the cylinders would be minimal...

hmmmmmmmmmmmm

I've thought of this question for a while and haven't come up with a good answer. Seems like it would work. My question though is oil is made to move in a particular direction inside the engine. If you just presurized the engine, what damage could you do to some of the relief values internal to the engine. Probably nothing but I dont' know. Some of the experts would have to chime in. Had I built the engine right the first time, I wouldn't have had the problem.