Thread: 350 rebuild help/tips

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I'm about to pull the motor from my '94 GMC Truck (5.7L 350 TBI) and attempt my first rebuild...so I have a few questions.

1) Is there a good "rebuild kit" with everything I'll need for the rebuild? I'm planning on stripping it down, having it cleaned and machined and then start the assembly. I'm about 95% sure of what I need, but it's that 5% that has me guessing.

2) What "specialty tools" will I need for this job. I've got a good assortment of hand tools and other shop tools (engine puller, engine stand, floor jack, jack stands...blah, blah, blah) but are there any special tools that I'll need, aka ring compressor, etc.?

3) What other parts should I replace? I think everything is good (it isn't running as strong as it used to...I think it's the rings, thus the rebuild). What are the other "while you are in there" parts that need attention?

4) Any tips for this project? Little gremlins that jump up and bite you?

5) Any other websites with information that would help me through this project? http://www.helprebuildingyour94GMCtr...ubicinchV8.com perhaps?


I'll be on this thread asking more stupid questions as this project continues. I'll probably be pulling the motor in a week or two, so I have a little time for research and preparation. Thanks, guys...

I'd put in cam bearings while it's torn down. If you're re-using the pistons, tap them lightly and listen for a dull thump that means it's cracked. A good one kinda rings.

I've had decent luck with Summit's kits in mild rebuilds.

I would suggest you have the machining done first so you don't have the wrong pistons, etc if it needs boring.

I agree with new cam bearings and I usually have new freeze plugs put in.

A good purchase would be a torque wrench.

While you may be able to rering your old pistons or maybe a 0.010" overbore would be sufficient, you will find the best (lowest) prices for an overbore of 0.030" and pistons will be cheapest on the 0.030" oversize (usually). New cam bearings are a good idea and new rockers and pushrods are not that expensive in the overall scheme of things. Why not add new Z28 springs to the heads and maybe shave the heads a little so the surfaces are flat and raise the compression just a bit? I would suppose it is easy to get a 3-angle valve job on your old valves as long as the seats are OK. While the heads are apart the cheapshot enhancement is to smooth out only the exhaust ports but not bother with the intake ports to maintain good fuel mixture. There are a number of inexpensive rebuild/overhaul kits available under $300 once you accept the 0.030" overbore idea; boring and honing might be about $8-10 per cylinder.

Don Shillady
Retired Scientist/teen rodder

Once inside the engine, you'll need a breaker bar as the main bearing cap bolts can be tight. To get the pistons out, you'll need to rent a ridge reamer (I suggest you rent as they are about $70 to buy and you'll only need it once). Feeler guages and plastiguage are nice for double checking the machine shop's work when they are done. Micrometers are expensive, even I don't have any yet. If you buy pre-fit rings as opposed to file fit and the machine shop gets your cylinders bored correctly, you wont need a ring filer. You'll need a harmonic damper puller. A torque wrench is a must. Some people recommend oil pump primers, but they aren't required. I will just lube everything up real good with assembly lube and crank the engine over without spark plugs until I get some oil circulating. I just tore down my old engine and I am listing all of the tools I used and the ones I will use when I reassemble it.