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Posted by: SLITS Jul 26 2011, 07:54 AM

Ok, finally got around to start checking The Grey Ghost for the upcoming endurance test to Ouray, CO. I've had an oil leak(s) I have been trying to trace down for sometime now. Thought it could have been, in order:

1.) Warped valve covers

2.) Improper tightening of chain housing covers or valve covers

3.) Cracked oil tank

4.) Only Dr. Ferry knows

Anyway, got the car on the lift on Sunday to look again. I looked and didn't find anything out of the ordinary (being old and blind, nothing is out of the ordinary).

Brought in a second set of eyes (no, not my glasses) and wella ... found something that caused extreme distress ....

There is a shaft in the chain housing that chain gear #1 (tensioner) sits on. The shaft had backed out of the housing and was only stopped by the head from completely backing out. If it had backed out, one can imagine this large piece of steel being wound up in the cam drive chain, sucked into the bottom of the case and ... well you might get the picture .. (didn't take any images)

It appears that this shaft is pushed into the boss and the backside is epoxied (factory) to seal it. Now whether the shaft is staked in the housing I cannot tell.

Anyway, I was able to push the shaft back into the housing and engage the boss in the front cover of the chain housing.

I am going to stake the shaft and then re-epoxy the back side to seal it and pray for the best (epoxy doesn't stick to oil very well). Boss does not appear to have been ovaled out.

I know that this would have let go somewhere around Beaver , UT.

Anyway, one leak down ........ Game still on.

Not sure if this is a problem with /6s or just the 2.7.

Posted by: gms Jul 26 2011, 09:02 AM

This usually happens when an engine is rebuilt and the builder puts chain housing in solvent and does not clean and reapply epoxy on the chain tension shafts.
There is a good chance your housing hole has become oval, I would replace!

Posted by: J P Stein Jul 26 2011, 09:20 AM

A fairly common occurance with magnesium chain housings. Those shafts (steel)are only pressed it to the mag. Couple that with the fact that the shafts are not as hard as the chain wheel pivot thus they notch the shaft oblong (making a step in the shaft). Some think this notching helps lead to tensioner failure( & shaft walking)....include me in that "some". Your displaced shaft will just walk out again.....the epoxy is just used to seal the shaft/housing interface.
My orginal bits went into the recycle bin.

The cure for this is $tone expen$ive. Aluminum chain housings hold the shaft in much beter. Bushed wide foot pivot arm are also necessary....been there, did both 10-12 years back when it was less expensive.....but not cheep.

I've included a pic showing the ten & pivot wheel on the same shaft.


Attached image(s)

Posted by: SLITS Jul 26 2011, 10:23 AM

Thanks both of you for the replies; your advice is very sound. My thought was to replace the chain housing also, but to move the car around and not have it leak oil everywhere, I thought I would do the temporary repair.

I have another engine ready to go, but that's another story.

Oh, I am running solid tensioners to not worry about failure of stock or Carrera tensioners.

Flame away

Posted by: sixnotfour Jul 26 2011, 12:34 PM

Common on CA. cars that run hot. your fix will probably last the rest of what life that 2.7 has left in it.

Oh ya the solid tensioners may have contributed because you have set so tight.

Posted by: SLITS Jul 26 2011, 03:32 PM

Thanks Jeff ... Your Sogginess has a way with words that make one feel so worthy.

Now, where did I lose that 7R case?

Posted by: Cap'n Krusty Jul 26 2011, 03:36 PM

I wouldn't EVER use solid chain tensioners unless I knew I was gonna get the resulting major repair work not too far down the road. They're real money makers for me.

The Cap'n

Posted by: SLITS Jul 26 2011, 04:33 PM

Thanks John ... I feel much better now.

Posted by: PRS914-6 Jul 26 2011, 04:51 PM

If the hole is not egg shaped and still round, you can clean everything with no residue cleaner and use Loctite Stud and Bearing mount and press the shaft back in. Then re-epoxy. The Stud and Bearing stuff is super strong and the shaft will not move (as long as the hole is straight. Every time I have used this stuff it required significant heat to separate the two pieces.

Posted by: Root_Werks Jul 26 2011, 05:08 PM

I had a 75' 911S years back that the....drivers side kept back out on me. I kept pushing it in every day before going to work.

So just do that!

Posted by: SLITS Jul 26 2011, 05:57 PM

Thanks Paul for the Loctite advice.

And Dan, you just gave me a brilliant idea ... I going to machine a piece that will fit between the head and shaft, jam it in so the shaft can't back out.

Posted by: sixnotfour Jul 26 2011, 08:03 PM

you are so slits, that will work.

Posted by: proto31 Jul 26 2011, 11:34 PM

Hey, I'm pretty sure you should be using JB weld or equivalent.

Dan

Posted by: Dave_Darling Jul 26 2011, 11:56 PM

Are they SOLID tensioners, or just the older-style non-hydraulic ones? There's a big difference.

Solids are generally not recommended for a lot of reasons, one being the potential to contribute to situations like this. (Another being that they'll be too loose when the engine is cold, or too tight with it warm. Neither of which is particularly good.)

--DD

Posted by: SLITS Jul 27 2011, 06:53 AM

Dave ... they are solids, not early tensioners.

Engine has 100K on it and this is the first problem to rear it's ugly head. Borrowed this engine due to broken ring lands (#1) on my previous 2.7 which will go back in as I have repaired it.

I am still learning about common problems with Sixes. This thread and replies have added to my knowledge base.

Posted by: J P Stein Jul 27 2011, 08:16 AM

One learns where the term DAPO comes from. It seems that DAPOs intended each of their fixes were "temporary" and then got lost in the shuffle. "Sure, the motor runs good. It just has this small oil leak that should be easy to fix."

OK, Slits' fix IS temporary but will it be for some yahoo reading about it?
A quick fix for a 1000 dollar problem (double/triple that if you have it done).....nah, that will never happen.....

Posted by: SLITS Jul 27 2011, 09:07 AM

Love ya JP .... before this engine goes anywhere, it will be repaired correctly. Maybe I shouldn't have been so "light" in my replies, but then I have a fuched up personality anyway.

Car is still on the lift so I can pull the engine.

If newbies or ??? are reading this, there is only one correct way to repair what has happened.

Posted by: SLITS Jul 31 2011, 07:00 PM

Here's the temporary fix so it doesn't leak oil all over the shop:


Surface roughed up with crocus cloth, sprayed with brake cleaner, wiped with alcohol (several times). One layer of JB Weld, then covered with fiberglass mat impregnated with JB Weld, then a small coat of JB Weld over that.

Now, before you "spurts" fly into action, let me start the song for ya .... ready?

"Who's the leader of the club
That's made for you and me
M-I-C-K-E-Y M-O-U-S-E
Hey! there, Hi! there, Ho! there
You're as welcome as can be
M-I-C-K-E-Y M-O-U-S-E"

Carry on ya'll ...............