The Stovebolt Site Forums The Shop Area Engine Shop 1956 235 rebuild questions

Hey guys,

I finally got my 235 over to the machine shop. They called me yesterday, and it looks like the last owner did a number on the top of the cylinders with a ridge reamer. The worst taper is on the number one cylinder at .025, which would explain my 90 pounds of compression. Also, three different compression rings were broken, and three lifters apparently came apart. I didn't think solid lifters came apart, but that's what he said. I now have a few questions:

They said they are going to try to bore the number one cylinder to take a 040 piston, and if it's too big they'll sleeve it down to 030 and bore the rest to match. Am I better off with a sleeve and 030 or boring all 6 to 060? I know pistons/rings are available up to 080, is going to 060 going to cause overheating? Machinist recommends the 030 and sleeve, because it will allow another rebuild down the road if needed, and should run cooler. Is he just trying to sell me a $100 sleeve?

Second, I'm debating rebuilding the motor myself, or having him do it. Cost to assemble the shortblock is $320, and I think that money could be better spent on a t-5 swap. The problem is, I've never rebuilt a motor before. Going off a Chevytrucks article, http://www.chevytrucks.org/tech/engine4.htm, it doesn't seem all that complicated, although the article talks about shims on the main bearings, I don't think they apply to a truck engine. Assuming I get a copy of the assembly manual along with parts from Patricks, is there anything else I should know, or will need? Any special tools outside of a torque wrench and ring compressor?

Finally, while at the machine shop I am going to have them drill and tap the nose of the crank for a SBC dampner bolt, is there anything else I should think about modifying while the engine is apart? I read someone mention installing a speedi-sleeve, are they always necessary?

I know this is a ton to read, and I appreciate all the help. Too many questions!

Vince

What size and year engine?

Is the rebuilder providing a warranty?

If you do the "rebuild", and anything is wrong with the machine shops' work, you are SOL.

Drilling and tapping the nose on the crank is probably a good thing. How much $$ for that work?

A speedi-sleeve is only necessary if you a groove/grooves where the seal rides.

1956 235

Re-builder will offer a one year warranty if he assembles, will only warranty the machine work if I do.

I don't have a quote for the crank yet, I'm going to ask him about it on Monday when I tell him whether to assemble the block or not...

I'm confused on the seal/groove for the speedi-sleeve. Is the groove in the crank? He's going to grind the crank, will that remove any necessity for a sleeve?

Hy Coachie, the groove you are inquiring about would be worn into the surface of the harmonic balancer, where the balancer passes through the timing gear cover, hope that helps.

Sorry,

The groove is in the crank's "snout", where the old seal "rode" on the snout.

Grinding the cranks means grinding the main-bearing and rod-bearing journals on the crank.

Good luck, and keep asking questions. There are few things so nice for enjoying our trucks as getting a properly rebuilt engine. There are few things worse in enjoying our trucks/hobby than paying $$$ for a badly rebuilt engine.

I'd spend the extra money and get a good/clear warranty in writing. Re-install and test the rebuilt engine immediately upon getting it back from the shop.

If your engine does not have shimms on the crank mains you should look at and consider this mod. I just did and it went in just fine and I hope it works as advertised.

http://www.enginebuildermag.com/Article/1766/old_iron_sealing_stovebolt_chevy_engines.aspx

Hey Homer, I like the idea of a one piece seal, and less leaking. Did you modify your block yourself, or did the machine shop do it? Any leaks?

The warranty you don't want: "50/50 parts & labor".
This means he inflates the cost of everything by 100%, and you pay for the whole thing.
If he installs the engine, does the install go with the warranty, or do you have to R&R it yourself?
Assembly $320 is 4 hours at $80, but it may take you 20 hours. What's your time worth?

I didn't modify it myself. The machine shop that did my work was not familiar with it or didn't have the equipment to do it so they had another nearby shop do it. I haven't run my engine yet, I may paint it today or tomorrow, I'm still early in the process. Dave

I pulled the motor and brought it to him, and will re-install myself. They're a machine shop only, no diagnostic/other auto work.

Good point on the 50/50 warranty, I didn't think of that and will ensure what the warranty covers.

I didn't think the rebuild would take me 20 hours, is that realistic? I was assuming 6ish, but to be honest that was 100% guess.

The time really adds up when you double check everything and follow the shop manual. Don't forget to throughly wash everything and check EVERY oil passage in EVERY component, I found a problem that way. Dave

Dave,

That's why I'm a little inclined to rebuild myself. As much as I trust the machine shop, I'm sure I care more about my motor than he does. If I rebuild, I can double or triple check everything, including the cleaning. But then I lose the warranty. Decisions, decisions.

When I had my 235 machine work done I knew about the shims for the crank. I bought them and after looking at what it takes to put all that in I gave the shims back to the machine shop, NAPA, and they did the crank install for me for a nomial fee. I forget what it was but it definitly was worth them doing it instead of my time, plus peace of mine.Larry

I might stand corrected but 1956 chevy engines had Hyd. lifters. I've got one in my truck now. Not good. Hard to keep any oil pressure. Just a thought. That's probably why he said some lifters came apart. Check with Hot Rod Lincoln and see if I'm close to right. Good luck.

No original truck 235 engines came from the factory with hydraulic lifters (except maybe if the truck 235 was matched with the Powerglide option that available near the end of the 235's years, 60-63).

All car 235 engines from 1956 and newer had hydraulic lifters.