The Stovebolt Site Forums The Shop Area Engine Shop Best way to remove bell housing on seized engine

Okay, over the years I have read and done this several ways. As the saying goes, "there is more than one way to skin a cat" so I would like to hear from you all. For all of the cat lovers out there, rest assured no cats will be harmed.

Here is the situation. I am in the process of junking a 1946 235 that is seized. The cylinders have been steeping in a mixture of acetone and ATF for years with no success. The head hasn't been pulled to see the extent of corrosion. Recovery of the flywheel and bell housing is desired. What is the easiest and least time consuming method to gain access to the pressure plate bolts? Some have said that the bolts can be removed without rotating the crankshaft, but there is always one or 2 of the 6 pressure plate cover bolts that have no wrench access. Other methods entail torching the pressure plate cover, but I don't really want to huff asbestos. Removing the rod and main caps and then driving the pistons out works, but is time consuming.

This old dog wants to learn a new trick.

It can be done, get you a U-joint extension to your .5” ratchet system. They can all be removed, did it on a 270 a few years back.

Ed

I use a 3" diameter hole saw in a variable speed 1/2" drill motor on the pistons. Use lots or cutting oil and the piston cuts like warm butter. It cuts the piston crown away just inboard of the rings and frees up the crankshaft so it can turn. Those cast iron pistons are going to be junk anyway, as most anybody who would rebuild the engine is going to bore it and use aluminum replacement pistons.
Jerry

I freed up a badly seized antique Lawn Boy by adapting the spark plug hole, through a series of fittings, to a grease zerk. Grease gun provided the hydraulic pressure and popped it loose pretty quickly. It also made a terrible mess.

On a 4 stroke engine, you’d have to know which cylinder(s) were the problem and would have to loosen the rockers to get valves closed. And even then, you might have to inject a LOT of grease, before anything happens.

I like Jerry’s hole saw idea much better for your situation.

Even if the hole saw doesn't completely free up the piston, a few whacks with a BFH on a block of hardwood in the cylinder will finish the job.
Jerry

Paul WNCLast one I done was a gift of tremendous corosion,torched the pressure plate and clutch center. With the clutch disc clamped you wont get any asbestos,take out flywheel bolts,knock it off on the ground.Or you can torch the junk rods,take the crank out,probably save the crank. Once the rods are cut might drive out one at a time and have a boreable block. So lot of variables there

Remove the oil pan & cut the crank in front of the rear main brg.

Isn't that a little drastic, as well as hard?

Why go to that work destroying parts, easy enough to do with std. U- joint ratchet?

Ed

Wrenchbender Little drastic,hard on your torch too,if you snip the rods can save crank.

Once it warms up outside a bit, I will try the ratchet and u-joint method. It didn't work once on a different engine in the past...maybe I wasn't holding my jaw right during that attempt? Hopefully this old 235 engine stopped in a place that will allow removal of the hidden bolts. If not, I will work my way through some of the other methods mentioned. I suppose GM design engineers never worried about disassembling dead engines. Thanks for the responses.

I had the same issue several years ago. I loosened the rod caps and was able to get a straight handled wrench in there.