55 CJ5 Battery Issues - need your help

[tahoewilly]

Ok folks - winter is over and I've managed to enlist a neighbor who's been helping me trouble shoot a bit. Right now our hypothesis is that the engine might be getting tired. We tested the pressure and it was yielding about 50-60, well below what's needed to fire this thing up. The other issue may be related to the timing gear set.

Here's my question - what's the right sub-group to ask around if anyone is selling an L4 engine and/or a timing gear set that works for a '55 CJ-5?

[LarrBeard]

Ok folks - winter is over and I've managed to enlist a neighbor who's been helping me trouble shoot a bit. Right now our hypothesis is that the engine might be getting tired. We tested the pressure and it was yielding about 50-60, well below what's needed to fire this thing up. The other issue may be related to the timing gear set.

Here's my question - what's the right sub-group to ask around if anyone is selling an L4 engine and/or a timing gear set that works for a '55 CJ-5?

Just comments:

50 -60 pounds of compression is way too low - is it consistent across all four cylinders? It could be worn rings, valves or a combination of both.

Timing gear stuff is available from Kaiser-Willys.

https://www.kaiserwillys.com/vehicle...h-4-134-engine

You ask about an L4 engine in the same sentence as mentioning a '55 CJ-5. The CJ-5 had an F-134 engine originally.

[bmorgil]

Checking compression on a stone cold engine is more of a how well it pumps up in a few strokes and consistency between the cylinders. The process outlined in the service manual is the way to check a cold motor. Refer to paragraph C-7 in the Universal Manual for the procedure. Somewhere we discussed this before on this forum. Using only 4 complete strokes to diagnose each cylinder, you are looking for how fast the cylinder pumps up in four strokes and how consistent each cylinder is. There isn't a spec for "cold compression" Until the pistons warm up and "fit" the cylinders, considerable compression is lost. Once warm you can look for the correct psi compression numbers. Since the 134's have less than 7 to 1 compression, 50 to 60 psi on a used cold engine is possible. I think it will fire up if you get 60 psi in 4 strokes on all cylinders, if it comes up quickly. If the first stroke gives you 70% or so of the total psi reading, and the next three strokes bring it up to the highest reading, that is what you are looking for. For the first stroke to give you a good squeeze and the next three bring it right up to a maximum number, at stater cranking speed all spark plugs out.