Carb question.

Hi

I Have a 2 month old motor(258) I had a hard time getting it running, had to set timming to 30 something degrees to get it to run initially. I did the nutter bypass and stripped off or sealed off everything that was old leaking or not needed. The carter pulse air system was finally removed 2 weeks ago when the brand new professionally rebuilt motorcraft 2100 arrived.

Instantly my vacuum leaks and wierd issues went away. I had the engine idling at 150 rpm and it was really smooth. I adjusted the idle cam about 2 full turns and brought the idle back up to 650rpm exactly. I pulled the distributor vacuum and set the timming. I had no problem at all getting the engine to 8-9 degrees. The engine ran great at all RPM's. I have a manual choke and since the engine was warm I left it wide open. I decided to go for a quick ride around the block and the engine falls flat under a load and often back fires. It seems to happen in all gears above 1200 rpm give or take. As soon as I had it back in the parking lot and the clutch in neutral the engine was smooth and strong from 600rpm to 4500 rpm. It seemed to have plenty more to spin but I did not want to push it. I normally drive at about 2000 maybe 2500 at most.

I know the motor and current carb has no vacuum leaks. I soaked the engine and every gasket and hose with starting fluid and propane. No change in the rpm. As far as I can tell no leaks.

So is my problem in the new 2100 or my distributor? Oh the vac advance is working perfectly. Plugs are new, wires and cap have not had any problems before. Also its a ford electronic pickup 83 cj7 not the points that most of you had in the 70's cj's,

I'm thinking about bringing the timming down a degree or two to about 6degrees. I am really afraid to start adjusting the carb. The guy I bought it from is a jeep pro and insists he tuned it perfectly for a stock cj.

Thanks for any suggestions!

 

I spent the morning messing with the jeep. I still don't quite understand the problem but I advanced the timming a lot. Its back up to 20 degrees or more. Engine drives great, It likes to have a little bit of a rich fuel mixture but overall its running well. I'm happy for today, but if anyone has thoughts on how to get it right, I'd be happy to hear them.

Thanks.

 

I would check to make sure that the timing marks are correct. The balancer on my 72 was off by about 25 degrees when I first purchased the Jeep, it wouldn't run correctly unless I set the timing to about 35 degrees at idle. Also check to make sure that the mechanical and vac. advance are working. Good luck