I have replaced the vaporizer on my '26 with a swivel-type Holley NH, using the nifty conversion linkage 6299CL. But I'm having trouble with the throttle control rod, which with this linkage still goes over the engine like a vaporizer throttle rod does, but it operates the NH throttle.
Part 3535B does fit, once you figure out the orientation, and it goes okay across the top of the engine. But it's too short - with the throttle fully closed at the carb, the throttle lever in the car has to be about 1/3 or more the way down. On the other hand, my original vaporizer rod is basically long enough, but the ends are not bent in the correct orientation to make the linkage. I reckon I could just about bend my vaporizer rod to work. But I am reluctant to do that, because I want to save it in original condition in case I ever put the vaporizer back on. I understand reproduction vaporizer throttle rods are not available, so I don't want to mess mine up.
Does anyone have any experience with this issue?
Tom I can't see enough detail on the picture Lang's has - but it seems to me like that part 6299CL should be adjustable - meaning you should be able to loosen one end (it looks like maybe you can adjust the bottom end by the carb) or the other and adjust how much rotational difference there is between the top piece and the bottom piece. Even if there's not a way to adjust it by loosening a screw, I would just bend it, or in this case twist it, before messing with your original vaporizer linkage.
Can you post pics of the linkage?
Thank you, Seth. I will look for a way to do that tomorrow, and post a photo. I did some more searching and found that this problem has been mentioned before (near the end of the thread) but without a solution being mentioned.
Bend yourself a new throttle rod of proper length in a vice - I always do that when I try a new carburetor.
When you've tested it and know the length is OK, then drill holes for cotter pins.
I'd check your block first to see if it has the hole for the throttle rod. If it does, then get a standard throttle rod and put it in. As far as the steering column throttle rod, I don't know if the hole is drilled for the arm or not, but hopefully it will be there.
There are clamp on throttle levers available too, but it shouldn't be necessary in this case?
Here are the promised photos
The arms at each end of the vertical rod are at a fixed angle and can't be rotated - and in any case the top piece is already pointing quite far towards the steering column side of the engine - so I don't think there is any gain in length available there.
I'm afraid my block does not have the hole through for the throttle rod, and I'm reluctant to add one. So the solution will be as suggested by Roger Karlsson - I will find some 7/32" steel rod and fabricate one.