Inspection Milestones during Engine Rebuild.

[autobonrun]

Reading all the horror stories on engine rebuilds scares the hell out of me. Primarily, what I see is that other than doing it yourself, you have to trust the individual /company doing the work. A flashy web site does not guarantee anything with respect to rebuild quality.

Many just send their engine out and hope for the best. As stated by others on this board, an engine running strong for a few thousand miles doesn't say it was done right. With 202k miles on my 79SC, I know my day will one day come where I have to do a rebuild.

My question is this; Are there some key milestones that can be put in place to allow inspection and review during the rebuild process? For example, can all the parts be machined to spec and those specs demonstrated to you before they are assembled? Can the use of shuffle pins (if purchased) be shown before the engine is enclosed?

In the engineering field, I know we always use inspectors on key pieces of equipment, and those inspection milestones have to occur before the manufacturer continues the process. Many also will recognize this procedure if they have had a home built from scratch. Is this procedure something that is or can be used during engine rebuilds? I think if a rebuilder would not allow me or my representative to inspect the engine at some key assembly points, I would walk away.

[Wayne 962]

Best suggestion for that would be to visit the rebuilder every couple of days to check on progress.

I'll say this again. It is a matter of trust (how do you know you're heart surgeon is going to do a good job?) and reputation. People who will stand behind their engines and give you a guarantee are the ones that you want to go with. Any of the builders I mentioned in the previous ad will do that. My partner used to work with John Williamson (Otto), and he remembered a story where a 914 engine was shipped to Europe or some other far away place. It blew up (sometimes these things just happen), but John took care of it. I'm sure he wasn't happy about it though...

Anyways, the best way to protect yourself is to know what type of questions to ask - just like going in for heart surgery. I know I've been plugging the book a lot lately, but it's true - this knowledge is not published anywhere right now. Even the factory manuals don't tell you what to do, because they are showing you how to put together a NEW engine, not a rebuilt one. The Bentley manuals are just a more detailed copy of the factory manuals - no real insight into what you need to know.

I've spoken to many, many, many experts in the field over the last few months, gleaning information from them. The only big thing I can't really get any good info on is porting - everyone seems to have their own little secrets.

Be armed with the right information, and ask the right questions. If you don't like what you hear, then move on...

-Wayne

[autobonrun]

Assume that the major players in Porsche motor rebuilding are located in say 5 cities across the US. An inspection company would hire an individual in each of those cities that would be contracted out to inspect engines for individuals. This would be more practical than trying to travel yourself if the rebuilder is not located in your city. Even if he is, having a knowledgable inspector do the inspection for you would help, and would mean you would not have to take time off from work. I would envision the inspector using a base checklist plus some client preferences that he uses to perform the inspection. Based on the rates I pay for other mechanical inspections, I think this would add no more than $200 - $300 to the price of a rebuild. To me this is a small price to pay to insure the rebuild is being done as I expect and is around 2 -3% of the price of a rebuild. From what I've seen, inspection helps insure trust is not misplaced.

However, I'm curious what the inspection milestones could be. Possibly:

1) Receipt of all new parts and completion of machining rebuilt parts

2) Bottom end assembly
3) Top end assembly
4) Final inspection before shipment

Does this sound possible and is it being done now?

[Superman]

Your '79 engine will not need to be shuffle-pinned.

Perhaps the two most critical moments for measuring are:

1) At the moment of complete disassembly. Measure all the old parts, including cylinders, pistons, rods, crank, valves, etc.

2) After machining/new parts acquisition. Measure all the new and reconditioned parts just before they go together.