VCCA Home Forums TECHNICAL - 1945 AND NEWER 1949-1954 1958 engine in a 1953 Belair

My engine seized - I have a 1958 6-cylinder engine as a back-up. I know it will fit - what I do not know is if I am now committed to changing to 12 volts or will the engine fire with the original 6 volt system - any opinions? Would really like to keep it 6 volts if possible.

Use the 1953 coil, generator and starter.

I agree with bobg -

I have a 62 235 in my 48 running 6 volt system, and I have absoutely no problems with it. Turns over just fine and fires immediately.

Just personal opinion here, do what you want, but if it were mine, would leave it 6 volt.

Best to ya in whatever you decide.

Jim.

My advice is keep it 6 volts. The "problem" with converting to 12 volts is all the other "problems," like lights, gauges, bulbs, etc. etc. I've had plenty of occasions to go to 12 volts, but never did. Just my 2 cents.

If you use the 1958 engine and the 53 6 volt starter you will need to use the 53 flywheel since the 58 and 53 have different starter teeth and the flywheel starter rings. What are you going to do about the water pumps and fan and pulley differences? If you use the 58 waterpump setup you will need to change to a 58 generator pully and fan pully, won't you?

Here here. I agree with all the other posts too. Keeping it six volts is the way to go. Converting to 12v means having to use current reducers for all your gauges and fuel tank sending unit.
Mr. Mack's post is key--make sure you keep your 53 flywheel, bell housing, AND starter. The 58 mill should bolt up right in place of your old motor as Chevrolet had the genius to leave the outside of the block unchanged with all the original mount holes. Check with Patrick's Antique Trucks in for the shorter water pump.

Your choice but unless you're street rodding it, keep it 6v!

The 6 volt system will crank a newer motor just fine. I use lighter oil (10W-30) rather than single grade in my 54 235.
You might find your starter cranks a little slower if you're running the heavier oil.

Also, make sure you get a 12v coil if you decide to switch over.

Okay - have ordered the short water pump and have the generator, coil, and starter ready to go.

How do you get the bell housing and flywheel off of the 53 engine that is seized? Engine will not rotate.

What caused the engine to seize? Was it running and quit, or had it been sitting for a long time and won't turn over now?

In order to remove the flywheel & bell housing, you will have to pull the oil pan, front timing cover, all mains, and remove the rod caps and turn or possible lift the crank up far enough to get at all the flywheel bolts. That is if the pistons are frozen in place.

From your other thread......
Or you could torch cut,the crankshaft, or use a cutoff wheel,which will take a while, close to the rear main, (or in the rear of #6 Rod journel) where the crankshaft is smaller. then remove the rear main bearing cap and then the flywheel and stub crank shaft should rotate and allow you to remove it.
I have tried to remove the rods and pistons from a really seized 235 and it can be diffucult since the crankshaft won't rotate, some of the rod caps are very hard to remove on an engine where the pistons are seized to the cylinder walls. I was not able to save the rods or the crankshaft, the only thing I saved was the flywheel, and the camshaft. Even the lifters were seized. I didn't see whether the engine was one with a manual transmission or a powerglide

Which gets us back to the other thread to the point where you need to unbolt the bell housing and turn it to remove the clutch so you can get at the flywheel bolts.

The reason I asked about how it seized is because it makes a little difference on how you dismantle it. If it was a bearing that seized, you just need to undo that bearing to rotate the crank shaft. If the pistons are seized, you have to remove all of the main and rod caps and such as Walt mentioned above and lift out the crank with the bell housing as I mentioned.

And MrMack mentioned that if the pistons are seized, and you aren't able to move any of them, you can't get all of the rod caps off, which complicates matters even more. But, the more you dismantle, the more likely it is that you can break individual parts free. Spraying PB Blaster or some such into the cylinders may help free up any pistons that are stuck....

Please let us know what you end up doing. It's kind of like a large, heavy metal puzzle. Good luck with it!

Not sure why Walt is insisting on rotating the old engine. On my 52 235, I was able to get at all the flywheel bolts once the bell housing and clutch were off on the back of the motor.
I'm guessing your 53 motor is similar so you shouldn't have to pull the main caps and front timing covers off.
???

I could be wrong; happened a few times before..... Does this engine's bell housing have a solid front with a hole that the end of the crankshaft goes through. I'm working with an old memory here, but that's what I recall. If it has the open front there wouldn't be a problem getting it off, but the solid front would be. The problem would be getting at the upper clutch bolts if the engine wouldn't turn.

I really do miss my memory sometimes, though.....

I have not insisted on any method of removing flywheel & bellhousing only suggested what has worked for me in the recent past. If the engine is siezed you cannot get at all of the pressure plate bolts and the bellhousing is the last part to remove after 1st removing the pressure plate and then the flywheel.

So Walt, are ya saying that my memory served me well on this one? ;-)

How about an update Paul? Ya gettin thet thang apart yet?

You don't have to change the gas tank sending unit,it is resistance and it doesn't care whether it gets 6 volts or 12 it will work the same.