MTFCA Forum

I'm considering rebuilding the carb on my '26 Roadster. The car starts well, idles well and runs good in low, but when shifting to high it almost wants to die and loses all power briefly. It will come out of it and continue in high. (Yes, I have newly rebuilt coils) Is it worth buying a rebuilt one or could I probably do a good enough job on my own? I've rebuilt a number of Chevy 6 Carter carbs.

Check carburetor mount on manifold for tightness, may need a new gasket, and also manifold tightness at the block.

Moxie26 wrote: ↑

Thu Jun 15, 2023 9:43 am

Check carburetor mount on manifold for tightness, may need a new gasket, and also manifold tightness at the block.

Will do that. I replaced the manifold and carb gaskets last year, but maybe I didn't get things tightened down. Maybe. I've been meaning to check the timing via the crankshaft end.

Depends - I've tried rebuilding carbs with usually unsatisfactory results.... When I send them out to Russ Potter for rebuild they come back good as new - ready to bolt on and go.

One mod I have done to mine and other's carbs is to install a Scott Conger "Full-Flow" valve which insures enough fuel gets into the carb on hills or when the tank is low. I have a '17 with the tank under the seat so that becomes an issue.

Good luck!

I dont smell a carb issue. When you are established in high does the car run good? Its a transition issue only?
Could it be your operation? How long you been driving a T? Is it possible your rear end has 3-1 gears?

To directly answer your carb question. There are specific steps in a restored carb. Get the book. Are you capable to rebush the throttle shaft, drill out the idle circuit passages, Do you have a torch to take it apart, the correct tools to remove the seat & jett, ect??

speedytinc wrote: ↑

Thu Jun 15, 2023 10:34 am

I dont smell a carb issue. When you are established in high does the car run good? Its a transition issue only?
Could it be your operation? How long you been driving a T? Is it possible your rear end has 3-1 gears?

To directly answer your carb question. There are specific steps in a restored carb. Get the book. Are you capable to rebush the throttle shaft, drill out the idle circuit passages, Do you have a torch to take it apart, the correct tools to remove the seat & jett, ect??

You could be right. It could always be me. A big part of the problem is that I don't get much exposure to driving it. I'm thankful that my wife was able to get 3 cars ('55 Chevy truck, 28 Sport Coupe & '26 Roadster) in a 2 car garage, but that doesn't allow much driving time for the T. It sits in the corner on dollies and gets driven about 5 miles once a month....maybe. That being said, I've tried shifting early, late, slowly, quickly. It doesn't seem to really help. I have thought about joining a local club, but I really don't have a lot of time to put towards it so that might not be real helpful. I've gotten a lot of good advice on here, but it's sometimes hard to put those techniques to practice when the car is in a bad spot. I'll get it....eventually. We're actively looking for a home with bigger garage space (so I can buy another T), but there is a housing shortage here and adding on to the garage is a possibility, but it's a year out.
I might not be able to to the machine work on the carb so that could be an issue. Next chance I get I'm going to see if there is dirt in the fuel line. Before I got the car the tank was cleaned and sealed so it ought to be good.

Drain some fuel into a glass jar from the bowl drain.

There are several possibilities. One is that the idle is set a bit too slow. Another is that it runs fine in neutral with the parking brake position in neutral but the adjustment of neutral with the low pedal does not give you as free a neutral as the parking brake. See attachment and follow it. Another could be the gear ratio, however, if you don't have many steep grades around your area, that would not be as critical.
Norm

speedytinc wrote: ↑

Thu Jun 15, 2023 11:10 am

Drain some fuel into a glass jar from the bowl drain.

Will do.

Norman Kling wrote: ↑

Thu Jun 15, 2023 11:18 am

Free Neutral.jpgThere are several possibilities. One is that the idle is set a bit too slow. Another is that it runs fine in neutral with the parking brake position in neutral but the adjustment of neutral with the low pedal does not give you as free a neutral as the parking brake. See attachment and follow it. Another could be the gear ratio, however, if you don't have many steep grades around your area, that would not be as critical.
Norm

I had thought that the Free Neutral was set properly, but I'll go over it again. Speaking of throttle too low....I can't seem to get mine to idle down. The screw has no effect on it. I keep bending and tweaking the rod to make it work. I even saw that they make a conversion kit to run the rod over the engine. Thought about that. I always completely throttle down to idle while shifting. I figured that was best. Maybe not?

Backing off the throttle when shifting to high is normally the correct procedure. Your fast idle problem may be due to a worn throttle shaft or loose throttle plate or loose throttle lever on the carburetor, or some issue with the linkage. When the throttle lever is all the way up, or nearly so, the carburetor lever should be in contact with the idle adjustment screw. I don't think you can get a satisfactory idle speed adjustment by using the linkage as a throttle stop.

Norman, I think I understand the "adjust yoke to have 1/16" play in direction shown", could you discuss/clarify it. Thanks, Bruce

There is a short rod connecting the low pedal to the clutch lever at the side of the hogs head. What that picture to the left is the end of that rod with an adjustment clevis on the end. Leave 1/16" in the direction shown where the clevis pin goes through. That assures that when the pedal is all the way back it will not be in neutral or slipping the clutch disks.
Norm

I’m wondering if you have the mixture set to lean. I’ve seen people doing this. I find that i definitely adjust the carb on my 27 (NH) in the middle of rich and lean. Just a thought.