What method would be best to determine the orientation of the holes needed to be drilled on new spark and throttle rods? I am installing a vaporizer on a car that originally had one, but the vaporizer had long been changed out to an NH, and I don't have the original rod for a pattern. I do have a 'handy holer' drill guide but to use it the holes must be drilled before assembly.
I would assemble everything in the car. Mock it up, mark, and drill.
I'd use the clamp on type for the throttle lever that Ford supplied. My Gramps changed out the NH for a Vaporizer on the family's TT grocery truck and that's what he did. I believe I have an extra clamp on throttle lead if you want it.
Terry, years ago I used an aluminum rod, easily bent, got what I needed, then transferred that to a steel rod.
I have some also,Bob
Terry, I hope you know that the throttle rod lever (P/N 3531B) for the vaporizer is a different length than the one (P/N 3531) for the NH. Offhand I don' remember which is which.
Thanks for all the suggestions and keep them coming. The problem I see with 'mocking it up' is that you have to get the rods in place before assembying the gearing gear box in the steering tube and once they are assembled and the bottom of the shaft sticks into the lower steering gear bracket, I can't use the handy holer, which is the main reason I bought it. Then, I would have to do the assembly; mark; disassemble; drill; and reassemble. Seems like there ought to be a more time saving way. I did think about assemblying and try to just 'freehand' drill with everything in place, but I'll only get one shot at getting it right. As for length of rods, I think the throttle rods were longer than the vaporizer rods and should be long enough to shorten. The spark rod should be the same length and lever position. the ploblem with measuring from the top end, is the bend and the problem with measuring from the bottom end is you don't know if the throttle rod has ever been shortened . I have one set of re nickeled rods and one set of stainless steel rods.
The replacement lever that goes on the throttle shaft does not have to be drilled it clamps on. I may be wrong, but if I recall you can install it with everything in place.
Vaporizer throttle rods have not been available for some time now.
My car is an original very late 1927. If you set the spark all the way retarded, thusly:
Look at the bell crank, it is positioned up all the way. If it moves more to the car's right it will bash into the steering shaft. Thus:
You can easily do this mock up with the steering in a vice on the bench.
I forgot you said spark AND throttle. I had the throttle set almost closed and took this one:
If you close the throttle the bell crank goes vertical.
It is possible that there was some variation on how they were drilled (punched?), but this is how it was done on my car.
Too bad that original car has a phillips head screw & a nylock nut showing....
Yep, Mike that breaks me up, if it weren't for that Rusty would be a 98 point show car!
Thanks Terry, for the information and the photos. They provide the clearest pictures and information that I have seen yet. So, it appears that if both the spark and throttle rods are installed, fully retarded, that the levers are installed on the rods in a 12 oclock vertical position. If so, this will make it easier to install. Thanks, Terry W.
I did the conversion back to a vaporizer on my '27 and set the throttle lever all the way up on the steering column and then put the bell crank straight up on the rod. That was the easy part. I had a lot of trouble with the throttle rod from the column to the carburetor however as it required an awful lot of tinkering to get it right. I finally used a soft aluminum rod to get the bends correct and then transferred it to the steel rod. I also wound up getting another valve cover without the hole fro the throttle linkage that runs through the block. I doubt it is necessary but since I was trying to make the conversion as correct as possible I thought it would a good idea.
I have a couple of the non-hole valve covers and an original vaporizer to throttle rod shaft; so that part was covered. The stainless spark and throttle rods are undrilled and the renickeled spark and throttle rods were off a car originally equipped with a Holley NH, so to use either, I needed to know the placement and orientation of the levers.
My throttle rod was missing so I made up one being careful to keep away from the spark plugs. Worked great for well over 10 years but then i got an original rod ... boy was that slick, fits and works great, looks good. No one has noticed the difference (or ever will). It's one of those things your wife looks at and asks why in the world I spent money on that rod. Best thing is that she doesn't know how much money I spent!
Just got this info from owner of original '27 T:
"The hole for the vaporizer throttle arm is 7/8 in. below the hole for the retainer spring and in the same orientation as that hole on my original 1927 car."