So the old carb (motorcraft 2150) on my 302 was leaking fuel everywhere. I ordered a re-man carb from advanced, and put it on tonight. Didn't notice it right away, but an EGR port that was previously covered with I *think* the old gasket at the manifold, is now partially exposed. it's got a crappy sounding exh leak. I finally got around to taking it for a ride when I was done, and the truck feels LESS powerful. the motor is a 1980 302, and the old carb was from '81. and at some point, the carb was taken off. I know this because the gasket I took off at the manifold was from '85.

the tag on the old carb is:

E1TE
CMA
D 0J 16

my prolem is this, I can wind it up in 1st gear ok, not as snappy as the old carb, but ok. slap it into 2nd, and it runs out of breath at 3,000-4500 rpm, and makes a wierd exhaust note and the motor feels like it's got a high end miss when it hits that rpm range. with the old carb it would pull pretty hard up to 6k. 3rd gear it feels less powerful.

what can I do?

 

Check to see if the carb accelerator rod is indexed correctly.

There are 4 positions.

The sheet of paper that camw ith it has the index hole info on it.

 

Sounds like the float level is too low.

 

so is it running too rich? orrrrrr..........?

 

there wasn't a sheet of paper for it, however I looked at my old carb, and it indeed was indexed different. it was on the lowest point. SO I put new carb at the same setting, since it was in the middle of the 3 settings. Well not much happened, it still runs out of breath now at 4000 rpm. the exhaust changes tone in and out and feels like a high end miss.

what else should I do?

 

should I try adjusting the timing? I wonder if teh vac advance went bad..

 

Did ya chance the location of the vacuum line on the new carb? You want a port that has 0 vacuum at idle. 2) Or dose the new gasket extend into the intake hole? You did adjust the low speed jets as they are not preset as a rule.

 

Hi Taz, I'm thinking back to your first post about this, you mentioned a partially exposed EGR port and a crappy exh leak. If I guess rightly, you mean the bottom of the carb doesn't match the top of the EGR block exactly? I've noticed this before on some of my carb swaps. Sometimes if I'm trying a newer carb (late 70s - early 80s) on one of my older V8s (late 60s - early 70s) I'll have to fashion my own gasket out of flat gasket stock to go between the carb extension block and the carb (sort of a similar problem to your egr block not matching up). Then you can marry up the two different surfaces without any leaks and begine to tune out your carb. Not a perfect solution but if you do have 2 different surfaces, carb to egr block, this might help.

 

Well I gave up and got my old E1TE-CMA carb back. This was AFTER i put ANOTHER re-man carb on my 5.0L. reman #2 made it run WORSE. SO, I got my carb back this aftn, got my refund from parts store, got the correct EGR gasket for the manifold, AND i pillaged the new carb of its' gaskets. Armed w/ a friends borrowed Chilton's light/heavy truck repair manual from the early 80's, I disassembled the old carb (holy crap it was way easier to take apart than I thought), cleaned the dirt/crap out w/carb cleaner, put new gaskets in, and accelerator diaphram (the part that was leaking gas originally), on my old carb from the new one, slapped it back on the truck. Viola! all power/drivability problems solved. I noticed that my old carb's power valve was different, the little gas inlet nozzle on my old carb has a clip (connected to the float) to raise/lower the needle, the new carb DID NOT have this. also the #'s on the main jets did not match on the new carb. on my old carb they're something like 51F.
I took my '79 for a long drive tonight when I had dinner w/ my GF, just to make sure it was fine. We went back to her place so I could show her dad my truck (he's got a really nice shape baby blue '77 F100/302/C5 auto/short bed/2wd/D44, with 70k original miles on it). I took him for a mad beat, he had no idea a 302 could be so snappy . I've driven his old F100, man it's so gutless, but it's still pretty cool to drive.

I kept thinking about a post that LxMan1 had about keeping your old carb and rebuilding it, since the success rate was so low w/ re-man carbs. Well in this case he was right.

-T