My Jr-8 ran about 15 years ago. After I bought it 4 years ago, I soaked the pistons with brake fluid & diesel fuel and the engine turned over easily. Now, after setting for 4 years, it is seized. Does anyone have any ideas on what I might try before I tear the engine down?
Thanks
Larry Harp
I've had good success with a 50 / 50 mixture of acetone and automatic transmission fluid.
Are you sure the problem is a stuck piston? I would also look at other rotating parts such as in the valve train, oil pump, water pump, etc. Stuck valves can also lock up an engine.
I can move all of the rocker arms so I don't think a valve is stuck. I am trying to decide if I should remove the timing chain to see if the cam will turn or if it would be easier to drop the pan and pull off the rod caps to see if the pistons move.
I have had excellent luck with Marvel Mystery Oil by squirting into each spark lug hole with a pump oil and letting it set for a couple of months. Then gently turning over by hand. Good luck.
Since I recently had my first success in unfreezing my 1923 A-22 engine, I thought I'd kick in my 2¢.
I put about a bottle and a half of Marvel Mystery Oil in each spark plug opening and gently rocked pressure back and forth with the hand crank. I worked it every couple days for a about 6 weeks without success. I pulled the engine from the chassis and put it into a cradle in the back of my truck. After the ~45 mile drive to the rebuilder, before removing from the back of the truck, it turned freely.
So, I guess my advice is: MMO, time, and taking it on a spin around town!
Where Are You From? Marysville, Kans
Do You own a car built by Durant? 1923 Durant A-22 Touring