Anybody know of a good mechanic to work on an old jeep?

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T34r1tUp

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i personally dont like flathead engines just because they are wwwaaaaayyyy before my time. unless you are wanting to keep it original i would just swap it a more modern engine.

if you got some $$$$ i would swap in a chevy ls1.

cdn.speednik.com_files_2012_04_LS1_Willys_3.jpg
 

71buickfreak

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What kind of tune do you have installed on the ECM? Where is your O2 sensor mounted? It sounds like it is staying it warm-up mode, and not going into closed-loop. It is dumping fuel, and that is why it is running rich. How rich is it? Does the EFI system have a laptop connection and a dashboard so you can monitor the sensors?

What is running hot? 200, 210? Newer engines are designed to run a little hotter than older cast iron engines. An LS1's run temp is 200-210, 220 is getting hot, 230 is aproaching the danger zone. How hot has it gotten?

I have a shop in Stillwater, let me know if you want to bring it up. That goes for you too, Cowman.
 

TMLoftis

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What kind of tune do you have installed on the ECM? Where is your O2 sensor mounted? It sounds like it is staying it warm-up mode, and not going into closed-loop. It is dumping fuel, and that is why it is running rich. How rich is it? Does the EFI system have a laptop connection and a dashboard so you can monitor the sensors?

What is running hot? 200, 210? Newer engines are designed to run a little hotter than older cast iron engines. An LS1's run temp is 200-210, 220 is getting hot, 230 is aproaching the danger zone. How hot has it gotten?

I have a shop in Stillwater, let me know if you want to bring it up. That goes for you too, Cowman.

Ive only let it get to about ~210 but it's still a cast iron block.

O2 sensor is right after the manifold.

It's not just real rich but it fouls the plugs after about probably 100 miles or more.
 

71buickfreak

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210 is not that bad, its warm for sure, but it will live at 210, cast iron and all.

I don't know much about that howell system, but it seems really low-buck. You need to be able to monitor the sensors, that is a key point. What kind of radiator are you running? If it is the stocker, it could be plugged up. Do you know anything about the motor itself? What kind of shape was it in when you swapped it?

We had a Mustang with a rebuilt 302 and a high-dollar EFI system and it was fouling plugs within a 100 miles or so. In the end, we upgraded to a learning ECM, and that fixed it. I suspect your problem is in the computer or you have a bad connection on your O2 sensor. The whole running hot thing is likely a secondary issue.
 

TMLoftis

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210 is not that bad, its warm for sure, but it will live at 210, cast iron and all.

I don't know much about that howell system, but it seems really low-buck. You need to be able to monitor the sensors, that is a key point. What kind of radiator are you running? If it is the stocker, it could be plugged up. Do you know anything about the motor itself? What kind of shape was it in when you swapped it?

We had a Mustang with a rebuilt 302 and a high-dollar EFI system and it was fouling plugs within a 100 miles or so. In the end, we upgraded to a learning ECM, and that fixed it. I suspect your problem is in the computer or you have a bad connection on your O2 sensor. The whole running hot thing is likely a secondary issue.

It's a new 3 core radiator.

The engine was rebuilt with 19k on it since the rebuild.

The howell kit is basically retrofitting a 4.3 V6 Chevy tbi system.
 

71buickfreak

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It is most likely an ECU programming issue then. If a sensor was faulty, then it would be tossing codes. Give me the fuel system details- Fuel pump, line size and type, regulator type and location, etc. I had an aftermarket EFI system that would run rich because we had a larger fuel pump in the car than it needed, it was pushing fuel past the regulator. Pressure was ok at start up, but it would creep at idle, once it got past the regulated pressure, it stayed there.
 

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