Rebuilding the engine
 

I've been kibitzing articles and videos by owners rebuilding their 986's engine. The idea of having a zero-miles engine sure appeals to me. My car's 155K engine has good compression and it's running fine, but that won't be the case forever. (Although I talked to a guy whose '96 had over 300K original miles and was still running strong.) I've rebuilt several engines, and my 986's 2.7L seems fairly straightforward. Have any of you folks rolled up your sleeves and tackled the job?

Bring lots of money and a pile of special tooling................

Care to elaborate?

There are a ton of "single use fasteners" inside these engines that are never supposed to be reused, there are very limited sources for piston rings and all bearings, almost no oversized units to compensate for worn crankshafts or cylinders (which cannot be overbored), so if your cylinder liners are out of round (which they probably are), you are in for $4-5K just for new liners at a minimum. If your piston skirts show wear, you are going to need new pistons, probably aftermarket units. You're are going to need Porsche cam retention and timing tooling, Porsche RMS installation tool, Porsche piston wrist pin tool, etc., etc. Some of these tools cost $500 to $600 each, and rentals are few and far between. There are very few areas where you can (or should) cut costs rebuilding one of these engines, which is why quality rebuilds from professional shops often top $20K.

Here are a couple threads that I remember from when I was new here. There are others that did rebuilds, but James and Alex have the best documentation from what I remember. Neither is going to serve as spoon-fed instructions, but there are many good points and some comments from the Porsche engine expert Jake Raby.
http://986forum.com/forums/diy-project-guides/54170-my-diy-engine-rebuild.html
http://986forum.com/forums/diy-project-guides/49562-engine-removal-rebuild-re-installaion.html

You will need to explore further, but I think that in both cases, they had engine difficulties later and have been gone from the forum for a few years.

You can also find many good comments from BYprodriver. He went through Jake's training and did some nice upgrading. Where the other two were figuring a lot out as they went, Bill knew what he was getting into from the start. Search his posts on your own, but save this spreadsheet in case the internet loses it: https://docs.google.com/spreadsheets/d/1roke7O_Yyigm8AaE1Gei1ncGhFN6sh9sgAE9H0gh9Ks/edit#gid=0

I have two engines in my garage that are too far gone to rebuild, but have been good to pull parts from - two other engines I have are going back into cars. I would caveat JFP's advice that the extent and definition of a rebuild should be factored with what you are starting with. Taking a low mile engine and doing full maintenance such as chain ramps, cam adjusters, IMS bearing and bolt-ons can be [much more] affordable. The correct Porsche tools are very expensive, but there are alternatives. Check here for blemish/bargains: https://www.ebay.com/usr/type4store?_pgn=1 Some of the alternative tools [and procedures] can ruin your rebuild. Personally I do not see the practicality of a full DIY rebuild vs buying unless you want to do it for the exercise and enjoyment.

With the stated milage of 155K on the engine, it is going to need a lot..............

Yes. My thought was not that it would be a good idea to do it with her high mileage engine.
Rather than doing a complete rebuild on something like that for a "zero-miles engine", what do you think about buying a +/- 50,000 mile engine for a few thousand dollars and doing maintenance on it short of splitting the case?

A low milage replacement is always going to be the cheaper route, even if you have to do an IMS/RMS update before putting it in. Problem with that is finding one that is (1) low in actual milage, and (2) not beat to death already. The 986's have been out of production long enough that the bone yards are pretty picked over already.

eBay always seems to have a number of complete 986 engines available, some from relatively low-mileage cars, for relatively reasonable prices, including warranty. Assuming, as you point out, that the seller is not misrepresenting the mileage.

JFP, I'm disappointed to learn the engines are such bears to rebuild, and so expensive. There are so many third-party sources for parts (much cheaper than Porsche's), I didn't anticipate that would be the case. I was sorta looking forward to dropping the engine, tearing it down, and meticulously reassembling it with new parts. You are a big spoilsport!

No, I am someone that has done it multiple times, and knows what you can get into with these engines. And as far as someone doing rebuilds and selling them cheaply, just remember: You gets what you pays for..................do it right, do it once................

One thing I've learned over the years working on cars is to always listen to those with greater knowledge and experience. Every forum I've ever been on, from C++ programming to this one, has had a Big Dog, someone who knows the subject cold. It became apparent early on that JFP is 986Forum's Big Dog. We're fortunate to have his input.

That.






Look. It's 4A. ;)

:cheers:

There are a few fairly large canines on this forum, but personally the two that always catch my attention are JFP in PA and 78F350... for different reasons.
I hope I don't insult anyone, but this is how I see it:
JFP explains how to do the best job so that the customer (or yourself) will be very happy and will never come back to complain. If your need a special Porsche tool, buy the special Porsche tool.
78F350 on the other hand helps those of us that are financially challenged, ready to take some risks mechanically and are willing to accept that if we screw up it's our own fault... and we are fine with that. If your need a special Porsche tool, have a look in the scrap metal heap and see what you can come up with...
Like I said there are a lot of others with experience who give very useful advice but these two are my favorites.

Grant, you and I (many of us) buy these cars as broken toys. We learn what we can from our mistakes and the helpful posts of others. Often we are are not concerned with doing things by the book. JFP in PA is a long-time professional and enthusiast. When I am looking for correct technical information or advice, I always include his user name in the search here and at Renntech.org. Much of the 'good' advice that I can give is based on what I've learned from his posts.

A dealer or shop owner spreads the costs of his tools across the income from fixing many cars as a business expense. He wants to match the tool to the car to the Porsche directions for max efficiency and customer satisfaction. He can't be waiting for a part or tool and still have happy customers. His reputation is all important.

One or two car efforts are different.

I did a full rebuild on my 3.2 M96 about 10 years ago. Then, there was almost no Forum advice. BY was a great help, so was Jake. I had no idea what I was getting in to. I had rebuilt many engines for old British cars but the M96 was a whole new level of precision ,skill and complexity. I did all the work myself except machining. I spent over $15k (10 years ago !) on parts and special tools and I was frugal. It was a ridiculous project in terms of time and cost but very interesting and humbling.The engine stills runs well but for the cost involved there were many wiser choices.