Tear Down almost done - pictures.
 

It's analysis and recommendation time.

I'll post these pictures and let them confirm the story.

Dropped #1 exhaust valve. 1975 911S 991/44 engine (CA) 54K mi on car, some evidence of engine work on the way in, like sealant behind L timing chain case. I drove 80 miles with the piston like that. Felt rough but I needed to get home....

http://forums.pelicanparts.com/uploa...1203310919.jpg

The only nugget I found in the case - lots of others at the strainer.

http://forums.pelicanparts.com/uploa...1203310992.jpg

Does this case already have timecerts? To me it looks like it - I'd be surprised.

http://forums.pelicanparts.com/uploa...1203311027.jpg

http://forums.pelicanparts.com/uploa...1203311057.jpg

http://forums.pelicanparts.com/uploa...1203311102.jpg

http://forums.pelicanparts.com/uploa...1203311370.jpg

Let your opinions and suggestions fly. Particularly a good Machine shop w/i driving distance to Redding CA.

Buy a 3.0

A bit glib, but this is great advice if you aren't married to the idea of a 2.7. They are perhaps the most bulletproof engine Porsche ever built and make wicked power.

Is that bearing surface damaged?
It looks like it.

I have almost two 2.7 engines worth of parts. One has been in the family and in the car for 33 years and only 54,000 miles. I'd rather rebuild a known engine than take my chances on what I can find on the market. I recognize the structural problems with the magnesium case which for the most part can be dealt with. A valve job will be more expensive to the tune of the valve guide replacement.

I agree that the letf crank journal in that picture looks scratched, grooved or otherwise worn. Its a good picture because my naked eye and finger didn't detect it. Maybe it will "buff out" with a polishing....

Any opinions on the head studs?? - are they timecerted already?? I did some kerosene case cleaning today so a cleaner picture can be taken.

I was not clear if mine had been done either. So I had the machine shop tear it down and inspect it and it turns out that they were not previously done on my 2.7. Have you thought about sending all of the parts to a shop to have them inspected, cleaned, machined and reassembled?

Hey I would rather rebuild my own than deal with an unknown too - but if I had a 2.7 - I'd look for a nice 3.0 or 3.2 to rebuild. By the time you do the machining - by the time you get that crank polished and magnafluxed - by the time you replace the engine oil cooler and rebuild your oil pump (or better yet, replace) you'll be in 3.X territory.


Sorry for the "glib" reply - but that's what I would do.

Just out of curiosity, how much oil was left in the engine after 80 miles of driving with a hole in the piston? What's the first / worst things to happen when running low on oil?

Rebuild the 2.7. I was pleasantly surprised when I got my case back from the machinist. This whole nightmare of machining costs for a 2.7 is a bit overplayed IMHO. Besides, have you priced a P&C set for a 3.0 and greater? :eek:

The 2.7 you OWN is a bird in the hand. I bet the purchasing costs for a 3.0 and rebuild would exceed the costs of doing your 2.7 correctly.

My .02

Thanks for the replies. Your input is helping me decide what to do. I do want to get my parts to a Porsche machinist and still want some recommendations in my general area. Prior to that I may bring the crank to a local shop to see if the surfaces are a concern. I need to tear down the 'other' 2.7 engine I bought cheap to evaluate replacements for parts that were destroyed (Piston) and damaged (cylinder, head and oil pump). I did finally rotate and look at my oil pump and it sticks a little and shows damage to a limited band of the scavange section. This would be what is picked up from the sump before the filter. It has been recommended to open the filter - I'll look into how best to do that - any recommendations?

I posed my bearings for a look-see. To me they do not show any horrible problems. The pitting in the intermediate shaft bearings seems interesting and perhaps a sign of the 16 years of little use this car saw.


http://forums.pelicanparts.com/uploa...1203744903.jpg


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>I was pleasantly surprised when I got my case back from the machinist.

I paid $1000 to a have a 2.7 case machined last year - resized to standard, stud inserts, etc. Nothing fancy.
What did you have done to your 2.7 case and what did you pay?
thanks,

-Chris

+1 on the bearing surface

To answer an earlier question - The oil drained from the engine looked fine and was short about two quarts from my 9 quart refill (no external cooler) a short distance before. So I did lose oil from the crankcase through that big hole in the piston. I kept my eye on the oil level and oil pressure gauges and they didn't vary much as I drove. I was hyperaware as I drove.

Tonight I pulled the # 1 rod and all the bearing surfaces looked fine. Even the wrist pin bushing attached to that piston looked undamaged.

So what about those head studs pictured above? Timecerted or what??

Will get the 'donor' engine up on the stand tomorrow and start the teardown as time allows.

I'm not sure what means - can you elaborate?

Case-savers, decked, oil-bypass, set to standard, etc. And it cost me roughly the same.:)

I'd say some of your head stud mounting holes have been time-serted, yes.

Thanks for the timecert ID. Some places do that fix rather than casesavers. the two explainations I've heard are not convincing. EBS racing in Reno uses timecerts becuse they have worked well and the company is a few doors down. A local VW shop told me that timecerts are preferred when you need space for the big bore spigots they use.

I'll take mine to be ID'ed by the VW guy.

I have been having no success finding a close specialty Porsche machine shop. Jerry Woods told me that they really don't do cases. Obviously Competition Engineering is a candidate but not a drive-in for me up here in Redding (150 mi N of Sacramento). AS much as I'd like to put it all in front of the same machinist, I think I would end up doing the crank polish locally etc.