Sorry for the newb question but does the air intake need to be removed to adjust the Idle Mixture Adjusting Screw? I'm in my drive way laying on the engine and cant seem to find a way in there. Need to tune the carb. Its idling at around 900-1000
Idle Mixture Adjusting screw (1 Viewer)
- Thread starter IslandJ
- Start date
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mattressking
10 digits to freedom
Nope, but you do need a long narrow flathead. You can access the mixture screw from the backside of the carb top. Flashlight helps you see while guiding. Has worked well for me for tuning the truck with all equipment installed.
NeverGiveUpYota
Dare me.
Make one of these. Keep the air cleaner cover on. Have a pen light in left hand looking through left side and alternate this gadget fir Idle Mix and a long flathead screwdriver for Idle Speed.
- Thread starter
- #4
I had to take the top part off. I couldnt get screwdriver in the adjusting screw.
I have the idle at about 650-700 now just gauging by the dash gauge, much happier at stop lights.
On the freeway I'm still pushing 2800rpms at 65mph though.
I have the idle at about 650-700 now just gauging by the dash gauge, much happier at stop lights.
On the freeway I'm still pushing 2800rpms at 65mph though.
LAMBCRUSHER
SILVER Star
it's evolving...
LAMBCRUSHER
SILVER Star
couple more generations and you'll have an SST...
- Thread starter
- #7
So that custom deal just fits right in under the air intake top hat deal?
NeverGiveUpYota
Dare me.
Yup. It’s short. I got the idea from @mwebfj60 so I can’t take credit. I put some white tape on it and a 1/2” of hose for being able to grab for twisting. I also have a glove that has the first two fingers cut off the first knuckle so my hand is protected from the heat but I can still grip w/ my fingertips.
Also mark one corner of your IM screw (look at the two halves and then eye it for quarters) w/ a vivid sharpie marker and you’ll have something to eye for keeping track of counting turns.
Also mark one corner of your IM screw (look at the two halves and then eye it for quarters) w/ a vivid sharpie marker and you’ll have something to eye for keeping track of counting turns.
- Thread starter
- #9
Thanks for sharing.
Patent Pending...
DFXR
SILVER Star
My PO (not a purist) drilled a hole straight down through both top and bottom of the air cleaner housing, then ran a short section of 3/8" hose through the hole to "seal" it. A long skinny flathead goes right thru the hose and down to the im screw. Not something i would do myself but i have no problem using it...
LAMBCRUSHER
SILVER Star
That is a very elegant mod... I’m gunna have to copy that P.O. of yours... I’m too old to be contorting when I don’t need to
LAMBCRUSHER
SILVER Star
Some brake tubing and jbweld...
Hmmmmmm. I always just do it with the air cleaner off. My engine purrrrs. I know what the service manual says, but I just can't see it making that much of a difference on our high tech tractor motors,lol.
DFXR
SILVER Star
It took me a while to figure out as well, but I finally got a longer flat head with a skinny handle, and I stood in front of the truck (caveat I’m 6’3) and leaned forward looking under the air cleaner at the mixture screw while holding the screwdriver behind the air cleaner and angled in to the screw. It wasn’t perfectly flush with the screw but it turned it.
This way I also was able to look at the tach on my timing light that I had hooked up.
This way I also was able to look at the tach on my timing light that I had hooked up.
All of these tricks work a lot easier on a desmogged engine. I too, have to pull my air cleaner, but I’ve gotten really good at moving it slightly out of the way now. I can’t wait to desmog
NeverGiveUpYota
Dare me.
Ive yet to see a carb on mud here w/o a tampered IM screw. Blame the long ago PO’s.
