I have a 1977 #s matching Vette. The engine has been apart since 2000 (someone overheated it and cracked a head). As you can see the engine has a lot of dirt and grime on it. There is some rusting in the cylinders. Am I going to need to get the cylinders machined and then get new pistons, does it just need a good cleaning, or is the block worth keeping?

note: That is oil on the cylinders not water.



Thanks

 

good question.

Im waiting to hear the answers.

good picture of the timing tab im missing. I know what to look for now.

 

IMO...if you are just going to drive it for a while, and there is not a ridge at the top of the cylinder, then you may be able to just ream the cylinders if they are not too far out-of-round. Just ream them enough to get the rust out.

With that said, if this were my car, I would have the block checked, bored, and rebuilt. If this is the original engine for the car, and you want to hotrod it, get another 350 and save this one for a matching number sale when you get too old to get in and out of the thing.

 

If it were my block I would borrow a hone from A/Z and run a hone up and down all the cylinders lightly enough so that you can move the crank and pistons and then I would drop the oil pan and pop out all the pistons and hone them again without the pistons and buy new rings and rod and main bearings and put it back together and drive it. With that head off and considering it was overheated it would be worth the tear down and rebuild.

 

I agree, clean, disassemble and hone, and look for cracks before reassembly

 

I would oil up the cylinders real good and save it. you would need heads and a overhaul at the least. I would just buy/build a 383 for it

 

I have a different set of heads that I got with the car.

 

If you are just going to hone it, I have a 4" ball hone that is just collecting dust. It is safer than the 3 stone hone. Send me a PM if interested.

 

In my case, I sent the bare block into the machine shop and had them soak it in an acid tank for 3-4 days. Afterwards, we checked the block over for cracks and measured the bores for taper and roundness. I got lucky and found the original bores to be within spec so we just had to hone the cylinders.

What I got back was a nice clean block ready to paint and assemble. With a little luck all the parts will be hear soon and we can start putting it all back together.

 

What are we talking for an acid soak and pressure test? I'm looking at the exact same situation as my block has been headless for about a year and the cylinders could use a bit of work. There's no ridges and a quick hone would probably do the trick, but I would sleep a whole lot better knowing I checked everything before reassembly.

 

The acid soak was $85 and machine honing another $90. I would recommend machine honing over a hand held unit to keep everthing straight.
Good Luck

 

It probably needs more then a hone job.
If ya have rust you got pits and will maybe have to go .20 over to clean the walls up.
And who knows what else lurks in there.
Have you tried to turn it over?

 

Any other precautions or tests that should be performed? I want to make sure I'm dealing with a perfect block. Anything else I should look into?

 

Cam bearings have to be removed and replaced after the block comes out of the tank. Although I haven't done it yet, all the oil and water gallaries must be rodded out with a good brush kit and everything has to be cleaned, cleaned, cleaned, then lubed down with assembly lube before it goes back together.

Here's what my block looks like so far:

 

Nice

 

Testwise though, is there anything else than should be done. I know all about the cam bearings and oil galleries, but is there anything else that could/should be done besides a pressure test, acid bath.

 

I'm not really sure what else there is with the bare block. I'm sure you could magnaflux for cracks to be sure the pressure test didn't miss anything and recheck your measurements. Anyone else??

 

If you are going to take it to a shop for soaking, ask them what it would cost for them to clean up the block, oil galleries, and to measure the cylinders (top, middle, bottom at 0 & 90 degrees), crank bearing bores and cam bores. They should also make a record of any problem areas they find. It sounds like this is relatively new to you, so having them check it out would be a wise move, IMO.

 

Thanks for the offer but I think that machine honing sound like a much better option.


Thanks to everyone! It is awesome how much info and tips you can get on this site.

 

Actually, if you REALLY want to know what kind of condition your block is in, you'll have to either have a shop ball hone it or do it yourself before you take it to a shop to have the bores measured with a DIAL BORE GAUGE before you go any further with it. If measuring it with said dial bore gauge proves that the bores are indeed within diameter and taper tolerance then you can go ahead with having it either a) Jet cleaned or b) Hot tanked,then magnafluxed to check for cracks. Since it cracked a head it probably blew a head gasket and got pretty hot as well so you'll want to make sure and have the decks checked for straightness, after which it either may or may not need to have the decks resurfaced. Once you've gotten past that point you can then concern yourself with either reboring and finish honing or just rehoning the cylinders. After that's done you can then have new cam bearings installed, which would have been destroyed by hot tanking. If you're lucky you'll probably get out of there for about $400, if not it can run upwards of a grand. Of course this can vary greatly depending on how reputable your machinist is and how much competition he has in your neighborhood. And before you make one more move- buy a copy of 'How to Rebuild Your Small-Block Chevy' by David Vizard and READ IT.