On T's with under the seat fuel tanks, there is very little drop between the fuel tank valve and carburetor fuel intake. So little, in fact, that the T can run out of gas before reaching the peak of an incline. Furthermore, in order to maintain the drop, the fuel line has to run dangerously close to the very hot exhaust pipe, which could cause a vapor lock, or a fire.
I was thinking that, one remedy to this would be to have an air intake and heat pipe, 2" longer than the current design, which would locate the bottom of the carburetor bowl close to even with the bottom of the engine pan.
Did anyone ever offer such an accessory and if not, why? Would the extra 2" keep the fuel to air mixture from vaporizing properly?
It would be interesting to make a set out of an old spare intake and heat pipe by cutting a 2" section out of each and welding it onto another intake and heat pipe to see if this is feasible.
Just a thought.
Jim Patrick
If this is so much of a safety issue, then why have more Ts not burst into flame? I think if the factory specs are stuck to, and/or common sense there should be no issues.
That said, I think you're right. Why not install a heat shield? I intend to add one to my speedster, and run the fuel on top of the deck and not below it, for this very reason.
According to the MTFCI Judging Guidelines, sixth edition, page 37, 1915 Centerdoors had a longer intake manifold that placed the carburetor lower to compensate for having the fuel tank under the rear seat. It doesn't say whether the heat pipe was also longer, can anyone with a 1915 Centerdoor comment?
I was thinking that a revised throttle linkage and choke wire would be necessary as well to accommodate a lower carb location...
I have seen an original 15 centerdoor that did indeed have a factory installed longer intake manifold such that the carburetor was in a lower position. I am sure those manifolds are like hens teeth to find. It would make a fun shop project to make one up and try it.
I have photos of it from the last Portland swapmeet in my flickr account. Can't place a link while here at work as they now block flickr.
Erich, if you know which of your albums it is in, I might be able to find your pics of the centerdoor.
Here is Erich's centerdoor intake picture:
Here's a Sunderman accessory intake that lowered the carburetor:
My dad showed me a trick used in his family on the T has tank. He put a 3/4 to one inch block of wood between the brackets and the frame. The gas flows freely to the carb. Downside, you don't get the warning starving sound on the hills and you can run dry on the flats. Ask me how I know. Joe R.
Here we go.
https://www.flickr.com/photos/bruckzone/sets/72157643440145184/
My photos from that meet.
I remember seen some of that stuff in the photos esp that red huckster at the end! LOL
Nellybell seemed like a faithful dog waiting in the fenced yard for you to come out and get her as I walked out that day Mark. Just had to take her photo. That was a nice meet. One of my favorites lately.
That Sunderman manifold above is a new one on me. What did the company say about it in the period sales literature I wonder?
Ha ha, just noticed that manifold has a short initial section that is square, just like their mousetrap carb.
I assume those don't work with an engine splash pan?