Wrangler Fuel Delivery Issues

NCJeepin

Well-Known Member
Joined
Mar 23, 2005
Location
Conway, SC
OK..

1989 Wrangler. 4.2 with the Weber Carb.


Jeep stopped running.

Removed fuel hose, turned over.. got short small bursts of fuel from the pump, seemed very weak.

Replaced mechanical fuel pump with new... Before hooking line to the carb, turned over again.. a huge flow now.

Buttoned up all the fuel lines... The jeep idles at about 2500 RPM.

no matter what i do to the adjuster screw it stays that high.


Im guessing i have too much fuel pressure????

What is a simple solution?

Thanks
 
inline fuel pressure regulator

Hey Bruce, If you give me A few minutes I'll try to find what pressure you need, & summit part #. I'll re-edit this post. Fuel psi. 4-1/2 to 6-1/2 psi. is the pressure you are looking for. SummitRacing.com 1-800-230-3030 Summit fuel pressure regulator SUM-G3131-1 is polished aluminum $35.95 ea. SUM-G3131B is black powdercoat $30.69 ea. you may want to check the inlet/float needle seat, in carb. since it's been over-pressured. Hope this helps. other regs were much more $$$. I have heard good results with must Summit brand products. though I don't think I have ever had any. Oh just noticed you replaced old one, & didn't say whether you got A stock replacement, or A hi-po unit. If it was A stock type replacement, it shouldn't be too much pressure. The only way to tell 4 sure is to use A gauge. big box parts store for those. might find A regulator there as well.
 
Thanks for the reply.. I did put a stock replacement on... According to weber it needs to be 3.5 psi... i'll put a gauge on it, and i have looked at the regulators too, thats kinda where i was going to go with this and you have pretty much firmed up my thoughts....

thanks.
 
The high idle is probably a vacuum leak, those motors are notorious for them. I usually hook up a smoke machine and find the leaks in about 30 seconds.

Definatly put a gauge on it to find the fuel pressure
 
3,5psi. for Weber.

NCJeepin said:
Thanks for the reply.. I did put a stock replacement on... According to weber it needs to be 3.5 psi... i'll put a gauge on it, and i have looked at the regulators too, thats kinda where i was going to go with this and you have pretty much firmed up my thoughts....
thanks.
Click to expand...
Yeah, if Weber wants 3.5psi, that's less than the Mc2100's 4.5-6.5psi. That rating depends on what the float needle valve can hold back, before it lets fuel past the seat, uncontrollably. So use their recommended pressure. & sha-ba-do-bang's recommendations are A good idea too.
 
fuel pressure regulator does nothing... vac lines look good,. any other suggestions?
 
Regulator does nothing?

NCJeepin said:
fuel pressure regulator does nothing... vac lines look good,. any other suggestions?
Click to expand...
Did you put the regulator in the line from the pump, to the carb? Also have you tried to move the throttle closed by hand, while (I'll use the term loosely) idling? Check that it's down on the stop screw. (idle adjuster)May want to check the float level. (per manufacturers recommendations) I'm not A carb guy, although I rebuilt my Mc2100. it's an easy rebuild,& setup, & I did it recently so it's fresh in my mind. Maybe some grit, got through the line, when you changed the fuel pump, & is stuck in the float needle seat? can't think of anything else.
 
Thanks for the reply.. my next move is to check the float in the carb... I put the regulator between the filter and the carb. I even dropped it down to .5 psi and it still does 2500, and also i can back out all the idle/mixture adjustments and there is no change at idle. This is a wierd one for sure.
 
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