Inliners International Forums General Discussion Electrical HEI distributor on Chevy 153?

So I'm having a strange ignition issue with the 153 in my CJ2a. It has a miss, and in checking the timing I noticed the timing light does not fire consistently on the #1 cylinder. I put the light on the other cylinders and they all seem to fire the light consistently. The #1 plug is black and sooty, the other three look normal. I swapped the plug wires between #1 and #2, same result, (#1 is still inconsistent, #2 is normal). I'm a little baffled by this as the cap and rotor look fine. I ordered a new cap and rotor anyway. I put a pertronix in this distributor about 4 years ago, could it be failing?
Question: My spare motor has an HEI distributor on it. Can I just swap that in? The only connections I see on it are for "BATT" and "TACH". Can I just give it 12V from the battery and run it? Doesn't it need a ground like the older coil has?

Try a different plug before you go swapping the distributor. If it still fires badly then more the likely the Pantronix unit is your issue.

Did you check the compression in that hole? Yes, try another plug.
Time on the side of the road has helped form my feelings about aftermarket HEI. When I ran it in my '53 pickup there was always a spare module in the glove box and a complete points distributer under the seat. Is the height on the other engine aftermarket or GM? I think there were two GM HEI distributers a small one & a big one. The big one is best but ugly.

So I changed the plug in #1 and that cured the timing light not firing. I put in new plugs, rotor and dizzy cap, and reset the timing. It started more easily and idled well, but it still stumbles on acceleration and I am hearing what sounds like a rod bearing knock under load. I swapped out the pertronix with points and reset the dwell, The engine ran the same, still stumbles and knocks under a load. I cannot hear the knock at idle anywhere using a stethoscope. I would have thought that I'd hear a bad rod bearing even if it wasn't under load. Could a bearing going bad explain the stumble on acceleration? Maybe I need to move this question to the engine forum.

Glad to know the plug fixed your first issue. as to a bad bearing making it stumble more than likely NOT the stumble could a carb or timing issue Or a combo of both.

What Larry said. Rods tend to knock as the load is coming off. That little slack time when it is not under heavy compression or power as you back off. It could be a wrist pin. I once had a knock that turned out to be an exhaust leak. As Larry said the stumble could be the carb maybe the acceleration pump or just some dirt in a jet.
No more traffic than is on this site I doubt if it matters where you post your question.

Timing is set to 4 deg BTDC, where it's been for the last four years. It definitely advances mechanically when I rev it a bit. Could a lack of fuel under load lead to the knock? Carb is a Weber 32/36 which is always a little limited on the accelerator pump as it only has a pump on one bore. But this is different. I'll try putting some vacuum on the distributor to see if it advances

Try bumping the timing up some more.

I gave it a thorough going over this morning. bad news is that cylinders #3 and #4 only have 55 lb compression. So I think I'm looking at a rebuild, at least the top end. I can check the rod bearings once the head is off, but this will have to wait until after hunting season as it seems likely to be more than a weekend job.

Might be the right time to look at a 181?

I thought about that. I happen to have two 153's, (both of which now need a rebuild), and I'm not sure I really need the extra HP from the 181, and resulting decrease in gas milage. I'd need to move up to a bigger carb, (which wouldn't be progressive), and fuel economy is a real concern for me as the CJ2a tank is only 10 gallons, and my driving is typically into the woods, away from any gas stations.

I'm a big fan of using what you have. Depending on the condition of your 153s you could almost build both with one v8 kit. Pistons, rings, lifters, rod beatings, valve springs, valves (maybe some head work). V8 kits are pretty cheap. You would beed Gaskets & main bearings.

For the 181 if needed you could most likely re-jet your carb. I doubt milage would change much. The bigger engine wouldn't be working as hard. You would gain some bottom end torque, handy in a 4x4. I have a complete 151 (iron duke) from a '80 ( I think) YJ ? It has a 2bbl carb and that carb and intake might fit some of the 181 heads. I believe it is progressive. I need to find something to stick that engine in.

I hate having to make these choices. It is one of the reasons I have so much junk sitting around.

The issue I've seen with the 181s I've looked at in the past are related to them being marine engines. Salt water life is hard on them, and the freshwater boats have mostly been sitting outdoors for awhile without the benefit of antifreeze. if I found a fresh take out, I'd consider it. But Like I said, I do have two of the 153s on hand, one of which I've been running in the jeep for the past 4 years.

I agree, there are a lot of rusty & cracked boat motors out there. They came is forklifts too. A good one of those would serve you well but if you are happy with your 153 go for it. Parts are plentiful. They are easy to work on and truthfully have plenty of power for any kind of 4x4 Jeep use short of all out show off crazy u-tube stuff. You can rebuild both of your 153s for what a 181 would cost.

I've been looking at 181's and it looks like I'd have $500 in one needing a rebuild, or over 1,500 is on "ran well when pulled". I think I'l take a shot at rebuilding one of my 153's.