Ed Hughes

I figured I'd start a new thread now that this is in progress.

Recap: I built the engine two years ago and spared no expense other than using my original pistons and cylinders which were within spec. I recently got a set of new Mahle 98mm 10.5:1 compression pistons and cylinders which are going in, along with twin plugging. I do not intend to split the case again.

So, the motor came out yesterday, and today I stripped the top of the engine down. I'll start on some exterior cleaning next weekend before stripping the topend down and removing the old "jugs".

Some pics from yesterday and today:

rusnak

Ed....(raises hand)....um....what is there to clean?

Ed Hughes

Well, it really comes down to making sure I don't get any contaminants in the case when I open up the internals. She does have a little oil around the breather on top of the case and general grit that accumulates.

Ed Hughes

OK, surprise #1. Whalebird made a comment on a thread a few weeks ago about how it isn't a bad idea to drop your engine every once in a while. It struck a cord in me, and I've always counseled people that it is easier in the long run to drop an engine to reseal top goodies, etc, than it is to do a partial drop and try to do the work in a compromised environment.

Well, take a look at my MOTOR MOUNT!! If this engine was not out, I probably would not have seen this, and it is only going to get worse. This is what is bolted over your crank pully, and what the engine support bar attaches to. It is what supports the weight of the engine. I've had this engine out twice, and I did have a crack at the ear right above this (non-structural) where the engine tin mounts to. That was welded and painted the first time I took the motor out, probably 6 or 7 years ago. I then rebuilt my engine two years ago, and recoated-no issues at inspection then.

Now, look at the cracks. The metal just looks plain worn out. It is sobering. I know Ruby puts out some decent power, and I do make some use of it, but wow!!!!

Peter Zimmermann

Ed: Fascinating. Maybe 20 years ago I wrote a brief tech article for PCA - LA about this issue. During a period of about a year my shop discovered this problem on about 3, maybe 4, '84 Carrera Targas. It scared us enough that an inspection of the pylon, using flashlight and mirrors, became a routine part of services done after that to all 1984/85 cars. We erred on the side of safety, and replaced (rather than repaired) a number of pylons. The problem seemed to be with manufacturing of a batch of mounts (improper cooling?), but we never determined the cause. I will try to find that article, but I'm not sure that I still have it.

Ed Hughes

Wow, that is interesting Pete. I've no interest in repairing this piece. My initial thought is that it may indeed be a high-strength steel or heat treated, for it to crack like that.

I believe I've found one off of an '85 to replace it with. There seems to be a different part number for SC's and '84-89. Is that due to the size of the crank pulley and the clearance required?

whalebird

Nobody wants to find problems, but there is satisfaction in KNOWING. This isn't a PPI; your keeping(not "getting") things right and prudent care and feeding of Ruby is fun for you. Finding stuff like this just feels good and is a sign of good things to come.
Cheers Ed.

cbad-box

Ed it looks like things are moving along. I will keep watching this post, hope I can stop by and check things out as you progress.

Mario

Peter Zimmermann

This issue came about just long enough ago that my memory is a bit fuzzy on part numbers, etc. I will have some time to look for the article later today, maybe if I can come up with it we'll have a little more info. FWIW, I don't recall seeing the problem on any models other than '84 Targas...

g-50cab

Wow Ed - better to find this now - than after that first track outing of the season...

Ed Hughes

No kidding on lucking out in seeing this now. When I have all that extra HP on tap soon, I'd have just ripped this part to shreads!!!

Mario-anytime, my friend!

dshepp806

What would be specific to that year (for this failure)?

Doyle

whalebird

Howdy Shepp. I was thinking about you...subtle Rush referance in post #190 in the now epic "amber lamps" thread in OT.

Sorry Ed. I promise not to derail your "epic" Ruby Redux thread. I'm keeping an eye on this thread and will be with you every step of the way. Hey, did you decide against the Extrudehone?

dshepp806

Greetings to you, too, bird. I couldn't find the "amber lights' thread" but will look further (don't go there much,..just occasions to argue with the theists..

This thread will be a good one,..hope Ed has lotsa' memory sticks..maybe we should offer up a collection (for the pics)? Very excited to see this process begin.

Best to you, Ed, on this process!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!,

Doyle

Peter Zimmermann

It seems like nothing more than a bad batch of engine mounts.

My shop saw a large number of broken valve springs in 1978 model 911 SCs, and it was a first for that. I kept some crude notes about them, and it dawned on me that all of the broken springs had occurred to the engines in the first 1,000 consecutive build numbers, by VIN.

The mounts are the same kind of deal, bad heat treating? A stamping problem? I talked with people inside the Porsche system, at the time, and they admitted nothing.