Hello all, new member here, great site! I'm working on my friends 88 yj. The thing has no low end in 3rd through 5th. If there is an incline at all in 5th, the thing won't stay above 60. Same deal in 4th and 3rd.
I know these are low hp Motors, but I thought the torque would make it climb like a billy goat. Here is what is driving me insane, she is lean, which explains the crappy low end. However, from all my research, the way this thing is setup, if anything, it should be REALLY rich. Here is the jeep in a nutshell:
Stock motor, exhaust, ignition.
New fuel pump
New holley fuel regulator, set to 5 psi.
New fuel filter.
Weber 34 dgec setup as follows:
-idle jets primary: 55 secondary: 47.5
-run jets: primary: 47.5 secondary 47.5
Idle screw is 1.25 turns from stop
IDLE MIXTURE SCREW IS 4 plus turns OUT!!!!
Timing is set to 10.
The thing starts right up, idles like a charm at 700 rpm. I checked all the vac lines. All the old stuff is gone, the vac advance is hooked up correctly to the distributor , as is the PVC and vent.
I bypassed the Holley thinking it wasnt supplying the needed fuel, runs the same.
The nutter bypass HAS NOT been done. Can the ECU still retard or advance the timing enough to cause this effect???
Im going to step up the primary idle jet to 65 and see if the thing just needs more juice?
Btw, checked for bad gaskets or cracks all around the intake side of the motor....nothing.
Any advice guys????? Please help me? Am I insane? Will this thing simply not climb hills above 35 mph????
Have you considered a possible gearing issue? I know that with mine (4.0L HO/ 5speed) just bumping up to 33's cut my hill climbing power substantially. If your friend has large circumference tires, making it more high geared, he could loose his uphill power. I don't know if that is the case, but I know that that is an issue for many people including myself. Good luck.
'94 YJ: 4.0L HO fi, 5-speed AX-15, Daystar 1.25" shackles, 17" JK wheels, lined tub, custom paint, Bestop Supertop, etc..
'88 YJ: 4.2L carb, 5-speed, stock everything. Banana-ish yellow. hard top. 26,XXX original miles.
My guess is ignition problems. Or the tire issues talked about. How big of tires and what gears in the Diff? Do you know what your timing is set to? These things can be real dogs unless certain things are taken care of
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89 YJ.. My first jeep and I won't let it go. ▀||||▀
Current Project: None... I disgust myself.
[URL="http://www.jeepforum.com/forum/f22/my-yj-build-adventures-thread-1356941/"][SIZE="3"][B]BUILDING THE YJ MY WAY[/B][/SIZE][/URL]
1. The drive train is completely stock, trans through the diff. Stock gearing.
2. it DOES have larger tires than stock, I need to check what they are. (I'm at work now) I believe they are BFG mud terrain. The jeep does not have a lift, but the tires do just barely fit in the wells without rubbing. My buddy seems to think they are 30.5x 15x 9's.
3. Timing is set to +10 I believe. Would taking some timing out help?
Something else you will need to check on once you bypass it -
Verify that the dist has the correct mechanical advance for your now bypassed ignition
It should be 15deg or more - just from your description you probably have the original type with only 6deg
Hook the vacuum advance up to manifold vacuum and cap the port on the side of the carb
Handicapped license plates are not for mentally handicapped people -
"Man has not yet evolved an inch from the primordial slime that spawned him." Mark Blankfield, Jekyll & Hyde... Together again