How to Repair a Stuck Engine

Stationary Engine List


| September/October 2000



Stationary Engine

While "barn fresh" engines are still appearing into the hobby, more enthusiasts are tackling the more serious restorations of engines which have stood outside in the elements for years or been through fires. A subject which comes up on the Stationary Engine Mailing List with regularity is how to free a stuck engine:

"On Saturday I picked up a McCormick Deering M 1.5 HP engine that will be a birthday present for my dad. While it's being given to him to restore, I would like to get a few things done to it before I give it to him, mainly getting the stuck engine freed up. The connecting rod is disconnected, and I have the head off. I turned it on end and have been soaking it in Kroil. I've given it a few whacks using a hammer and a chuck of lumber, but it doesn't seem to be moving. I know patience is probably the best tool for a job like this, but it's not a tool I'm very familiar with! Has anyone had any success using Kroil for this? I know it works wonders on everything else. I've also thought about making a steel plate to bolt on where the head goes and putting a block of wood in the cylinder and tightening it down to put constant pressure on it, but I'm afraid of cracking these holes out. Anyone have any ideas or tricks to share?"

I had a stuck engine a few years ago and it took about a month to get my rustbuster to finally leak through. I was using Gibbs-it. Great stuff! I had my stuck engine blocked up and would go out and give it a good rap everyday. After about a month there was fluid running down below the engine and I was able to pound it out without damage. I thought about taking it to my favorite machine shop and pressing it out with his 12 ton hydraulic press, but because of design of those engines it would be hard to block up under the ram without possible damage. I realize it's a gift for your dad, but sometimes haste can ruin a good engine.

I had a similar problem with an M. Since it is a sleeved engine you can remove the piston/sleeve assembly. That will make it a little easier to work with. I tried soaking it for over a year in Kroil. I heated the sleeve red hot with a torch several times and hammered it with a wood block. Nothing would move it. I finally made a slug that fitted over the head of the piston and pressed it out. Once it moved initially it was easy to move the rest of the way.

Patience, patience, patience! If you are not familiar with this, you need to learn to be if you are to play with the old engines. Without it you have the great potential to turn your engine into a piece of scrap metal and break parts that are expensive to replace. Depending on how bad your piston is stuck will dictate how long it takes to get out.

Since your stuck engine has a pressed in sleeve, I would suggest soaking as you are doing till it starts to creep through the rings. You may tap on it once in a while with a hammer and block to fit the piston. If you use too much force, you are going to end up with the sleeve and piston on the floor. Many of us soak engines for months to a year! I would not heat it due to the seals in the sleeve.