Lucihale
New member
Like the thread title implies, my 1973 CJ5 with a 3.8 feels like a moped running on dog farts.
To start-
Two bbl Weber carb. (Pretty sure. Previous owner.)
Aftermarket intake (Dunno Make or model.)
Hedman headers (Just put them on last month.)
all leads to 2.5" pipe to a really nice muffler and out.
New fuel filter, cleaned air filter.
Just checked plug gap.
Replaced head gasket about 6 months ago, replaced radiator at same time as headers.
New plug wires.
Okay! Clues-
Carb adjustments-
I just adjusted the carb to a leaner mixture and a slower idle. HOWEVER, everything I read tells me to adjust that correctly I should have the idle screw turned in just one turn and to adjust mixture from there. My engine WILL NOT run at that speed. It just stalls. And the lean-best formula for adjusting by EAR doesn't really work because I've turned his mixture screw in ALL THE WAY, and his idle didn't really change... Weird. So I went from what I THOUGHT was a fluctuation. The idle is pretty steady, but there are still fluctuations that don't change with mixture screw.
results?- It ran better for certain, but recently the gain seems to have reversed.:?|
Engine noise-
There is a decidedly "whirring" noise from the engine at higher rpms.
There seems to be an air sucking noise too at any engine speed, but it SOUNDS like it's coming from the carb itself, not the intake.
Symptoms-
The first 3/4 of the pedal don't really do much in the way of acceleration. There's a "false floor" that I can push it to and start to get some giddy-up, and then just a little more pedal left for MODESTLY more acceleration.
The original engine was supposed to put out 100hp stock, with the mods, and the tuning it feels like I got about 135Hp out of it at best. Now it feels like I'm running at about 90Hp.
The engine has to be reved to warm it up if it's too cold, otherwise it stutters and stalls.
My inline fuel filter is FULL. The old one NEVER did that. It would have a small amount in the bottom, the new filter is completely submerged in gas when I stop.
Possible associations-
I need a new alternator, the current one isn't putting out enough amps to run the headlights and the engine at the same time. I dunno if that would have this kind of effect, it didn't before.:?|
I've heard that if your mixture screw doesn't do anything for about 2 turns, you need a larger gas jet. Any validity to that? Because MY screw doesn't really seem to do anything at ALL.
Ideas? Help? Suggestions?
The end result I would like is an engine that will give me enough pick up to hit and hold 60mph. WITH the stock 3spd transmission. I will answer all and any questions to the best of my ability promptly after they are asked, this is my primary vehicle and I would LOVE to have it up to par. Thanks in advance!
To start-
Two bbl Weber carb. (Pretty sure. Previous owner.)
Aftermarket intake (Dunno Make or model.)
Hedman headers (Just put them on last month.)
all leads to 2.5" pipe to a really nice muffler and out.
New fuel filter, cleaned air filter.
Just checked plug gap.
Replaced head gasket about 6 months ago, replaced radiator at same time as headers.
New plug wires.
Okay! Clues-
Carb adjustments-
I just adjusted the carb to a leaner mixture and a slower idle. HOWEVER, everything I read tells me to adjust that correctly I should have the idle screw turned in just one turn and to adjust mixture from there. My engine WILL NOT run at that speed. It just stalls. And the lean-best formula for adjusting by EAR doesn't really work because I've turned his mixture screw in ALL THE WAY, and his idle didn't really change... Weird. So I went from what I THOUGHT was a fluctuation. The idle is pretty steady, but there are still fluctuations that don't change with mixture screw.
results?- It ran better for certain, but recently the gain seems to have reversed.:?|
Engine noise-
There is a decidedly "whirring" noise from the engine at higher rpms.
There seems to be an air sucking noise too at any engine speed, but it SOUNDS like it's coming from the carb itself, not the intake.
Symptoms-
The first 3/4 of the pedal don't really do much in the way of acceleration. There's a "false floor" that I can push it to and start to get some giddy-up, and then just a little more pedal left for MODESTLY more acceleration.
The original engine was supposed to put out 100hp stock, with the mods, and the tuning it feels like I got about 135Hp out of it at best. Now it feels like I'm running at about 90Hp.
The engine has to be reved to warm it up if it's too cold, otherwise it stutters and stalls.
My inline fuel filter is FULL. The old one NEVER did that. It would have a small amount in the bottom, the new filter is completely submerged in gas when I stop.
Possible associations-
I need a new alternator, the current one isn't putting out enough amps to run the headlights and the engine at the same time. I dunno if that would have this kind of effect, it didn't before.:?|
I've heard that if your mixture screw doesn't do anything for about 2 turns, you need a larger gas jet. Any validity to that? Because MY screw doesn't really seem to do anything at ALL.
Ideas? Help? Suggestions?
The end result I would like is an engine that will give me enough pick up to hit and hold 60mph. WITH the stock 3spd transmission. I will answer all and any questions to the best of my ability promptly after they are asked, this is my primary vehicle and I would LOVE to have it up to par. Thanks in advance!
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