Options on cheap rebuild of Chevy 235? (Page 1/3)
IanT720 MAR 16, 09:28 AM
Hey guys I scored a '55 Chevy Belair in fall. It's a true barn find, 235, Powerglide, 4 doors and patina . I got the car running and driving actually. The odometer says 50,000 miles. I believe it. I don't think the engine has ever been rebuilt. As of now, it runs smooth. But has lots of blow by, and low power. It burns a little oil on startup but smokes a lot from the breathers. I'm sure it's just worn out. Also I can actually rotate the engine easily by grabbing the radiator fan. So me thinks it has low compression, and coupled with the blow by. I bet the rings are shot. I'm on a very very tight budget. I already removed the engine.
-should I plan on new, stock rings and a hone?
-what do I measure?
-what's the limit where I need a bore?
I really don't want to buy oversized Pistons. But will if I have too. Opinions?

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1987 Fiero GTX 3800 Turbo... My Build, ST3 Cam, Lowered, Wheels, and pics enjoy!http://www.fiero.nl/forum/Forum1/HTML/089483.html

Thunderstruck GT MAR 16, 09:52 AM
Rings probably just stuck.

Try running some Marvel Mystery Oil through it.

Pour about a 1/2 cup into each cylinder, let sit for a few days (longer is better) and put about 25% of it in an oil change.

Works a good percentage of the time.
IanT720 MAR 16, 10:37 AM

quote
Originally posted by Thunderstruck GT:

Rings probably just stuck.

Try running some Marvel Mystery Oil through it.

Pour about a 1/2 cup into each cylinder, let sit for a few days (longer is better) and put about 25% of it in an oil change.

Works a good percentage of the time.



Interesting! Will try that.
Patrick MAR 16, 03:43 PM

Do those old engines have valve guide seals? If so, I'd imagine they'd be hard as stone by now.
IanT720 MAR 16, 08:45 PM

quote
Originally posted by Patrick:


Do those old engines have valve guide seals? If so, I'd imagine they'd be hard as stone by now.



No idea, but I'm sure it has something like that. I'm sure that's why it burns a little oil on startup. But not the blow by out the breather.
rogergarrison MAR 22, 09:18 AM
If you search around, Offenhauser made a dual carb intake and split (dual) exhaust manifold for them. Gives you quite a bit of pep. Its the same engine used from 53-55 in Corvettes.
IanT720 MAR 22, 10:28 AM

quote
Originally posted by rogergarrison:

If you search around, Offenhauser made a dual carb intake and split (dual) exhaust manifold for them. Gives you quite a bit of pep. Its the same engine used from 53-55 in Corvettes.



I've seen those, pretty cool! But my money goes to the Fiero

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1987 Fiero GTX 3800 Turbo... My Build, ST3 Cam, Lowered, Wheels, and pics enjoy!http://www.fiero.nl/forum/Forum1/HTML/089483.html

Hank is Here MAR 23, 12:39 PM
Ah the old stove bolt I6's. If it has 50K and has never been rebuilt it does need a refersh. It it were me...I would do an old school inframe ring job and lapping of the valves. Pop off the head, pull the pan and go for it. While not much cost but would be a little more time I would recommed replacing the rear main seal with one of those chinese finger trap tools. --I think by 55 they had stopped all rear slingers and had rear main seals.
IanT720 MAR 23, 05:03 PM

quote
Originally posted by Hank is Here:

Ah the old stove bolt I6's. If it has 50K and has never been rebuilt it does need a refersh. It it were me...I would do an old school inframe ring job and lapping of the valves. Pop off the head, pull the pan and go for it. While not much cost but would be a little more time I would recommed replacing the rear main seal with one of those chinese finger trap tools. --I think by 55 they had stopped all rear slingers and had rear main seals.



Alright you have to educate me a little, in frame ring job? Just fresh rings? Lapping the valves? Just like a 3 angle grind? And I believe it has a rope rear seal.
Hank is Here MAR 24, 08:03 AM

quote
Originally posted by IanT720:


Alright you have to educate me a little, in frame ring job? Just fresh rings? Lapping the valves? Just like a 3 angle grind? And I believe it has a rope rear seal.




This is all old school methods...at least to me. While I have never done it on a 235 in a car, I have done the head and valve lap on a 235 in a truck.
In frame...don't pull the motor just leave it sit in the car while doing the rings. Pull the head, pull the pan, remove the rod caps and bring the pistons out the top...replace rings, put back togther...viola! If you feel like it you could even run a quick flex hone on the cylinders.

Valve lap? this is not a full valve job, you don't really cut the valve/seats but just reseat the valves. Basically remove the springs, remove the valve, add some valve granding compound to the valve/seat and spin away. If you geel up to it hook a drill to the steam of the valve. If you replace the main seal it is good to loosen the main caps to get a little sag/wiggle our to geat the new rear main seal in place.