Guys

I've been lurking here on and off for years, reading your posts and loving it. I have a '93 Black Touring (bone stock) that I bought new in Jan '94. 5 weeks ago my engine went south, blown apex seals I was told. Long story short, I've had an engine rebuild done and took the opportunity to start some of the reliability mods, principally 3mm seals, a down pipe, new cat, boost gauge, new vacuum lines, etc. My question is ... can you guys offer any advice on what to look for or request to ensure a quality rebuild. I have no particular reason to question the work done by the tuner but we live in a "buyer beware" world unfortunately. Can you recommend any best practices (standard operating procedures) for assessing the work? Should I ask for a compression test report? I'm picking her up next week!!!! Can't wait.

I was on a road trip when the engine blew so I had it towed to the nearest reputable tuner which turns out to be a 5 hr drive from where I currently live. I'll be flying in to pick the car up and plan to drive it back. I think it's doubly important to assess the work done as soon as possible, so that I don't discover anything nasty either a) during the long drive home or b) some time later.

Any advice that you scholars can offer would certainly go a long way helping me ensure I get her back on all fours. Much appreciated. Thanks in advance.

 

The builder should definitely give you a compression test, but the real chance to discuss the quality of the rebuild was before and during the rebuild. What parts were replaced, do you have pictures of the housings/rotors/e-shaft, etc.?

 

Compression numbers for a fresh rebuild are really a moot point, especially if the engine hasn't been installed and run for a long period of time yet. I've built engines that made 80psi on the stand/dry, yet after 1 hour of run time they made 110psi and by 1000 miles exceeded 120psi. Add to this the fact that most builders use assembly lube/oil which artificially raises compression, and it's easy to see that any numbers given are pretty much meaningless until it's been brought up to full temp and ran long enough to burn off all contaminants and lubes, and allow the seals to seat to the grit finish of the housing.

Really, the time for this worry and your research was before you made your decision. What sort of parts get replaced, what sort of reputation does the builder have in the community, and what sort of warranty/terms are offered?

As for now, the best thing you can do is throw it in and see what happens. You're only going to offend the builder if you question his methods at this point, whereas had you asked these questions beforehand, it would have been considered a perfectly normal part of negotiations and research.

 

my thoughts exactly. some people do not replace rotary housings/have side plates lapped for cost effectiveness.. and the only way to tell this is to wait after the motor has been installed and/or broken in to see if this has been done. Hell i have seen some builders not even check the clearances of the rotor-apex seal groove area to see if they were within spec's...

Really the only way to find out is by running that companies motor, and seeing if it worked out good.

 

Ah, but the rebuilder in his case is R&R the engine. I would think any responsible rebuilder would let the car idle a bit and drive around to make sure everything's working properly. You make a valid point for a pure rebuild, but I would think an R&R would "break-in" the motor enough to at least make sure the compression is good. Maybe I'm wrong.

 

I agree. If it only takes an hour of run time to go from 80psi to 110psi, shouldn't the builder do that BEFORE sending the engine out? I would certainly pay a little extra to know I'm not going to be stuck with 80psi forever...

 

Ah, okay, that's somewhat unclear in the original post. In that case, I would normally let the car idle while checking for leaks and other issues, and then go drive it, usually 20-30 miles. I'd then check again for issues before calling it good. A compression check at this point is useful, but still not conclusive, since the engine's compression WILL raise up as it breaks in within the next 1500 miles+. Think of it as a pot of macaroni and cheese, and you're talking about tasting the macaroni before you put the cheese in...of course it's not going to be perfect. So just wait until it's done and then worry about it.

Besides, look at it from another point of view. Most builders didnt get where they are by being careless. So, its reasonable to assume that the builder has done everything he can, short of a human error, to put together a good engine. So, for you to come along and (prematurely) say that the engine isn't good and you won't accept it because it isn't making XXXpsi compression by X hours of runtime doesnt make sense and it's only going to make them wary of dealing with you.

After all, if there truly were a problem, the engine would have to come out and apart. At the same time, if you run the engine 2k miles and there is still a problem, the engine has to come out and apart. What's the difference? At least in the second example you gave it a chance to see what would happen. IT didnt cost you any more or any less to take that engine and let it break in before running the final compression check and forming your opinion at that time.

 

Guess you've never heard of Hayes...

Good point, I didn't look at it that way.

 

Guys ... thanks very much for the input. I appreciate that the original post was somewhat vague. There's a fine line between keeping it brief and blah blah blah I guess.

I have a history of dealing with the shop I took the car to. This is why I had the car towed to his shop in the first place (at considerable expense too!). On any given day depending on whom you talk to, some say he's the only game in town worth trusting in the Greater Toronto Area. He's been in business quite a long time and has built up a reputation ... trouble is he is a bear to deal with. So I figure he's still in business for reasons other than his "bed-side manner".

He doesn't give you much air-time, either on the phone or in person. Customers are just a buzz in his ear it seems. Anyway, because my engine blew on a long weekend and I was 400mi from home I needed to take care of the situation PDQ and figure out how I was going to get back to Montreal to continue working so that I could pay for the rebuild. He said it would take him a week or two to get to my car. Not a problem. I left the car with him and flew back to Montreal. Since then I've been operating at a distance which can be a challenge.

He's charging me a pretty high price for the rebuild. I'm okay with that. You very often get what you pay for. Some times this doesn't hold true ... for what ever the reason ... simple human error, carelessness, incompetence ... whatever. I told him up-front I wasn't going to nickel and dime him ... I wanted him to do the job and do it right, take his time since I was flying back to Montreal and wouldn't be back for about 5 weeks.

Anyway, the engine rebuild is complete. He mentioned that he replaced both rotors with ones that had already been machined for 3mm seals. He says he keeps a stock of 3mm rotors because he sends the rotors out to be machined. He doesn't do the machining himself. He also replaced one of the housings. So besides all the seals, gaskets, rotors and one housing, he didn't replace much else. He has already taken the car out for several test drives. The first time ... he discovered an oil leak between the flywheel and engine. He's fixed it ... admitted to having made a mistake. He says the car is running fine now. Excellent but I'd just like that added insurance by completing some form of checklist when I go to pick the car up but it sounds like there isn't really much I can or should do until the engine is properly broken in.

Which actually leads to the question of whether the 400mi drive from Toronto to Montreal will at all be detrimental to a proper break-in. I asked the guy doing the rebuild and he said no problem, the long, steady drive would be an excellent form of breaking in the motor. I would imagine I should probably keep it below 60mph though. Any thoughts? Thanks again.