When you do a complete engine rebuild (gaskets, pistons, ect) how many many miles do you add to the life of the engine? How hard is it to rebuild an engine? Is it do able for some one who has a pretty good understanding of engines? How long does it take to rebuild and engine? Is it really worth it? :yesnod: or :nono:

Thanks a lot :flag


[Modified by 69chromebumper, 3:34 AM 8/6/2002]

 

Well, several questions there and they are all a little difficult to answer because there are good rebuilds and bad.

I have seen rebuilds that added no miles to the life of the engine because it blew up on breakin, on the other hand I know of at least one rebuild that has over 100k miles on it. It all depends on the amount of care taken during the rebuild and the quality of the workmanship and parts that were put into it.

My personal rule of thumb (take with a lick of salt :lol: ) is that undocumented rebuilds are good for 30k miles. When I say undocumented I mean when you purchase a car and the person selling it says "The motor was rebuilt xxx miles ago" but he can provide no reciepts or documentation of any kind. The reason I apply 30k miles is because 90% of the time in my experience they (the seller) will claim 25-35k miles on this rebuild.

This obviously goes away from the intent of your question which points to you wanting to rebuild your engine.

How hard is it to rebuild an engine?

It is not hard to rebuild an engine, keep in mind that you will want/need/require outside help in the areas of machining (block preparation, attaching pistons to rods etc....) but the assembly portion is so well documented in an innumerable quantity of both good and bad books that anybody who knows (or can learn) how to use a torque wrench can accomplish it.

Go to your local bookstore, and read up on the process, buy a few of these books and read up. At the same time find, either through the forum, a local car club, or a local corvette specialist, a machine shop of good repute. Visit that shop and tell them what you plan to do, ask them about the types of services they offer, ask if they will give you a quick tour of the shop (this is something I use alot) if the shop is clean and reasonably uncluttered its a good thing.

Cleanliness is crucial in engine assembly (at least in my opinion) and a sloppy shop, probably means sloppy practices.

Is it do able for some one who has a pretty good understanding of engines?
Absolutely.

How long does it take to rebuild and engine?
Depends on how good a job you want to do. I rebuilt my oddfire Buick V6 over a weekend, including getting the crank welded and reground and one rod resized, this was cheap and maybe - maybe added 10-15k to the life of the motor ( I spun a rod and had to fix it - at the same time my other car - Big block monte carlo was down as I rebuilt that engine - that one took 9 months (money)) If you have the parts and the time assume 2 weeks (most of which is machining time and assumes that the shop cant jump straight onto your job) 1 week if they can get right on it is reasonable (and you have everything on hand)

Is it really worth it?
If you are the kind who takes satisfaction from doing something yourself and doing it right - there is little else you can do to your car that will offer as much. (except for maybe paint which is far more difficult) If you are an impatient sort and just want to get it back on the road, buy a crate motor or pay someone to do it for you. There are few shortcuts to doing this job right, but if you do...the moment that motor fires up you will feel incredible.

Take care - let us know what you decide.

 

I'm in the middle of this, right now.

Here's what I've learned, so far.

As mentioned, find a machine shop that is clean, with a machinist who will talk to you, show you around the shop, and describe the full process. The machinist should also be interested in knowing what you're aiming for and how much you want to spend, as this will dictate what direction needs to be taken. Does it have to be balanced? To what degree? What's the car going to be used for? How much do you want to spend?

Also, while you don't want to hurry the machinist, get a firm commitment on when you will have your engine back. Make sure the shop doesn't their dealer orders a priority. If they do, and their manpower is limited, your job will be shuffled to the back of the line. This is what I'm confronting right now, and it sucks.

If the machinist stands their and tells you how it's going to be, ignores what you want, is not receptive to YOUR ideas, walk out. Find someone else. My guy had actual examples, on hand, of engines he had built to the exact specs I wanted, using the exact parts I wanted. This meant a lot to me, and is worth a delay. He understood I was the customer, not the other way around. If you find a machinist who doesn't see this, run the other way.

Can you build it yourself? Yes, but make sure your shop is clean as can be. I have sand all over mine, from blasting. Not a good place to start. Also, unless you're familiar with the workings of a micrometer, leave the measuring to the machinist. I measured my crank journals, and they seemed fine to me. The machinist took a look at them, and found they were too far gone. It could have been built, but oil pressure would have been low. My rods looked fine to me. Further testing showed five of them to be out of spec. Thankfully, the block was fine. But it needed to be bored .30 over. My machinist won't bore without having pistons in hand. He measures each piston and then bores each cylinder to correspond with the piston. This ensures each cylinder has the appropriate piston to bore clearance.

Is all this absolutely neccessary? No. But it's the difference between a lackluster rebuild and a true blueprinting. And it's all the difference in the world, when it comes to building reliable, long lasting power.

Again, I was going to build it myself. But when I took a look at the money I was spending on the motor, I realized I wasn't up for an expensive learning experience.

If you want a good learning experience and don't mind the occassional hurdle, or outright mechanical failure, give it a shot yourself. As mentioned, there are tons of books regarding how to do this. And it's not rocket science. I drive my car 3000 miles a year, tops. So if I got 30000 miles out of a crappy rebuild I did myself, that's 10 years. Not bad. Something to think about. Right? Still, I went the other route. But I can easily see it both ways.

Good luck with it!

 

thanks guy I really am thank ful for the advice!!!!
:cheers: :cheers: :cheers: :cheers: :cheers:

 

Since you are 16 i suggest you take AUTO SHOP in High School/Tech school.
It it one of the few courses that give you useful knowledge.
30 years later i still remember my auto shop teacher, but nobody else :yesnod:

 

The other post petty well cover the process. My answer for " Is it worth it "

I say YES. I have done some good motors and I have done some lousy motors but when the guys are all sitting around talking about THEIR MOTOR BUILDER DID THIS--THEIR MACHINIST DID THAT--THEIR INSTALLER DID WHAT EVER. You will be able to listen and think to yourself I DID IT MYSELF!!!!!!
bob