55 CJ5 Battery Issues - need your help

[bmorgil]

If you have nothing in the circuit like a radio for instance that might have a capacitor in it, the only place I can think of for a significant leak would be in the charging circuit. In an alternator it is usually leaking diodes in the Alternator. In a generator it is usually leakage in the regulator. Leave the battery hooked up and disconnect the power to the Alternator/regulator circuit. Put your multi meter in there on milliamps and see if you have current draw with the charging circuit disconnected.

[LarrBeard]

I have a similar issue. My battery will run down over a few days. Now when I shut it off, I take the ground cable off of the battery. I can rub it on the terminal and see the very slightest spark. Everything on it is new with the exception of the ignition switch. When I get time I'm going to check out the switch to see if it is bleeding some current through that switch.

Yep, that little spark is a sure sign of a sneak path load somewhere. The M38 series with the24-volt systems are notorious for developing sneak path discharge issues.

[okiemark]

The easiest thing to check first was the alternator so I unhooked it and still a draw. And I mean a draw so small you have to turn out the lights and still barely see it, but enough to run down the battery over a weeks time. In the mean time, I just pull the ground cable off the battery when I'm not using it.

[bmorgil]

Mark, see if there is a very small amount of voltage at the + on the coil. Like millivolts.

[tahoewilly]

I love that we're all working on the same stuff! Unfortunately, the car is covered in snow (no garage) and I won't be able to dig into to some of these options until it melts/start to warm up. I'll follow up when that happens + when I've tried some of this stuff.

Thank you again to everyone who's reached out - I'm pumped to learn and get my hands dirty, I just wish I had a damn garage.

[LarrBeard]

Patience Grasshopper... the first requirement for a Jeep Project.

[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.

[tahoewilly]

LarrBeard, Bmorgil - thanks for the help (again). I'm going to tinker a bit further before I pull trigger on any new parts just to make sure I'm not missing anything. Will report back.