First thing, easy way to see if the engine runs. Throw some ether starting fluid into the carburetor, turn the key, and then crack some beers cause the engine is running. Well that isn’t what happened.
The starter clicked but the engine didn’t turn over. It was locked up. I pulled the plugs and put down a bore scope.
Well that is not good.
Remember this is an AMC 121 engine that is basically a Audi EA831. This block is aluminum silicon. The head is aluminum. Where did all this rust in the cylinders come from? This is cylinder 3. Looking on the porsche 924 forums, the head of this engine has stainless valves but steel valve seats. That is where the rust has to have come from. So we are dealing with rusty intake valves but the engine is frozen.
Over a couple days I soaked all the pistons in a mixture of ATF, acetone, and brake fluid. This mixture really creeps and loosens stuff up. I just poured it down the sparkplug holes. After a couple days of hitting the starter it finally broke free and started spinning.
We got an engine that spins! With the plugs out lets test the compression.
- 110lbs
- 90lbs
- 0
- 90lbs
So uh, cylinder 3 with all that rust is not happy at all. We either have a bad head gasket, valves are trashed, or rings are cracked. That engine head has to come off to properly check and fix the problem.
Lets see if we can get the engine to actually run before tearing it apart though. The carburetor needs to be rebuilt and the Jeep came with 2 rebuild kits and a spare carburetor for parts.