Thread: looking for your take on this...

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i bought me a '81 cj5 cheap that had a bad 4 speed trany. got that all fixed and now i am having trouble with the chevy 350. major symptom is it want to die with too much load. if i rev it in neutral it will rev well but under load it pops and cuts out. and will do it in neutral but not as much.

first thing is i am here because im not an engine mechanic. i have had the carb apart and it does seem to be clean. it is a 4160.the float seems to be good. it is getting good gas. accelerator pump is working good.if i screw in idle screws in it does die, so im thinking that the power valve is good. i am thinking that it is the timing. it has points.

think about it and let me know if anything seems obvious. i know the replace the carb distributor route but i am low on cash....

thanks
heath

Any engine needs three things to run, fuel, spark & compression.

Since you've checked the fuel suppy, continue on that vain and check fuel pressure (to be sure the pumps good and that there are no restrictions in the fuel line), then check the timing. If you don't have a timing light, advance the dist by turning it counterclockwise about 1/4" and see if it runs better.

If not, do a compression check and let us know what you find.

Good luck

Could be a cracked cam timing gear. That happened on me once on a 327. Ran fine as long as you were driving it easy. If you stepped on it fairly hard or was driving up a hill it would lose power. Found out that the gear on the cam was cracked. Replaced the gear and it ran fine after that.

thats the kinda stuff i dont think of thx.

Based on ease of Checking.

yes i did rule the fuel filter out. the comp was 115lb to 125lbs average would be about 120lb. can someone let me know how this sounds and about what ratio it may sound like.

thx

i rechecked the comp as i did it with other spark plugs in.

here are the readings with all plugs out and throttle held open

#1-140
#2-136
#3-135
#4-130
#5-137
#6-129
#7-137
#8-130

i do not have dwell meter i adj it by hand. i will try the meter as i will do anything to get this right.

thx

you got it louey. will do thanks.

how bout this.... the carb has vacuum secondaries. the do not open. could this be the cause of not dieing under load? they dont even budge. i want to put a diferent spring, but if they do not budge i am thinking that they may be stuck??
is there a diferent solution to the spring like riging it up to be mechanical??
thx

Originally Posted by had2020

major symptom is it want to die with too much load. if i rev it in neutral it will rev well but under load it pops and cuts out. and will do it in neutral but not as much.

At what rpm does this happen?

yes i set the dwell, adj timing put in short yellow spring in secondaries and new baffle. i am not trying to get lucky. i AM NEVER LUCKY. i would say under 2000 rpm. even a little lower. the secondaries are not opening. i can open them by hand freely but they are not opening with vacuum. i go try one thing then check if anyone has ideas then try that then come check here. i am going to check for vacuum leaks.... be back in a bit

thx

remember guys this is the first holley carb i have messed with. i am not trying to have you do the work for me because i dont wana get my hands dirty but because i wana drive this jeep and i am itching to get it going.
now i see that next to the mechanical choke there is an inlet i for air to the bottom left of the choke. on the side not the choke plate. it sucks air all the time this is not normal is it? there is no hose hooked up .

thx

Originally Posted by had2020

the secondaries are not opening. i can open them by hand freely but they are not opening with vacuum.

The secondaries will only open when the motor is under load. They will not open with you winging the throttle in the garage.

well that helps. now i guess thats why people do the paper clip thing...

dang dang dang.

how about this...
when i first got the trany fixed it would run down the road but cut out under quick acceleration. it had the main vacuum port on base plate open sucking air hard. after i pluged this it runs worse. i adjusted idle screws, points, timing, plugs. maybey smaller jets now... because it was getting more air before.... lol
i thought the 4 speed was gona be the hard part...
thx