surging
Thread Starter
Instructor
Joined: Jul 2003
Posts: 213
Likes: 1
From: zanesville ohio
surging
Just returned from a show and on the way home I noticed at low speeds 40 and under that I could hear more than I could feel like it was surging under load. Where I noticed it the most was like going up a grade or hill and when I would give it more gas it was not real responsive. Does this sound carb related like to rich,to lean?
Drifting
Joined: Sep 2004
Posts: 1,959
Likes: 1
From: North Bend Ohio
Surging is a lean condition. Your part throttle cruise metering is a touch lean. One step smaller primary metering rod should cure this. You'll probably get better gas mileage to.
You could also try one step stronger power piston spring with the original rods. This will get the rods up out of the jets a little more under cruise vacuum.
BigBlockk
Later.....
You could also try one step stronger power piston spring with the original rods. This will get the rods up out of the jets a little more under cruise vacuum.
BigBlockk
Later.....
Race Director
Joined: Oct 2002
Posts: 12,065
Likes: 2
From: Smalltownville Michigan
Cruise-In 5, 6 & 10 Veteran
St. Jude Donor '09
while your'e at it, check the fuel lines at the pump... the rubber ones could be pinching off...when mine did that, i thought I had carb issues... changed the hoses out for new molded lines and it went away...
Thread Starter
Instructor
Joined: Jul 2003
Posts: 213
Likes: 1
From: zanesville ohio
Would this also cause it to surge at idle in neutral? You can hear it and when I hooked up a vaccum guage you can see the needle fluctuate? Anyone have an idea what I should be looking for or how to go about finding my problem?
Drifting
Joined: Sep 2004
Posts: 1,959
Likes: 1
From: North Bend Ohio
Originally Posted by john1977
Would this also cause it to surge at idle in neutral? You can hear it and when I hooked up a vaccum guage you can see the needle fluctuate? Anyone have an idea what I should be looking for or how to go about finding my problem?
This would be a good time to check the ignition timing. Retarded timing will make the idle rough. If you have a timing light set the advance somewhere around 12 to 16 BTDC.
BigBlockk
Later.....
Thread Starter
Instructor
Joined: Jul 2003
Posts: 213
Likes: 1
From: zanesville ohio
BigBlockk; Sorry for the delay in replying,Yes it is a Q-jet and timing is at 12 deg. have been in the garage playing with it. I turned the idle scews in till they just touched and back them out 1 1/4 turn to start.It is not surging as bad but it will run for several seconds like 10to 15 sec.then you will hear it slow down a little then pick back up (100 rpms)
Drifting
Joined: Sep 2004
Posts: 1,959
Likes: 1
From: North Bend Ohio
Originally Posted by john1977
BigBlockk; Sorry for the delay in replying,Yes it is a Q-jet and timing is at 12 deg. have been in the garage playing with it. I turned the idle scews in till they just touched and back them out 1 1/4 turn to start.It is not surging as bad but it will run for several seconds like 10to 15 sec.then you will hear it slow down a little then pick back up (100 rpms)
BigBlockk
Later.....
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