While driving my 21 it starts out nice and peppy but the longer I drive it seems to lose power. I'm talking a small amount but I notice it. I have coilman coils and a new radiator, anderson timer, 6V, basicly stock. Bands seem OK. What else should I be looking at?

Butch,

It sounds rich to me. Have you tried leaning (clockwise) the mixture some as it warms up?

Tight valve clearances could also be the culprit.

Seth

Seth, Yes I fiddle with the carb adjustment while driving. When I adjust the carb it seems like I have only 1/4 turn on the screw where the engine seems "Happy" I will check the valves. Also installed new manifold gaskets.

Butch..may also want to check the tightness of the manifold clamps once the engine begins to heat. Tighten down the 9/16 nuts that hold them in place.

How many miles do you have on the engine? If it is recently rebuilt, the pistons could be expanding and will cause friction. If this continues it could sieze up. One way to tell if this is happening, is to crank the car when cold, and then again after it warms up and compare the tightness.
Norm

Norman or anyone else who would like to respond
my motor was rebuilt something like 35 years ago, sat and was never started. I had the engine out and looked everything over, all looked fine to me. Mine starts very hard in colder weather, can't hardly hand crank it without a wheel off the ground. After it has warmed up, cranks and starts very easily, 1 pull. I'm talking below 40 degrees with 10-40 oil. Is this normal? I'm switching to lighter oil next change. I do have a good free neutral once warmed up. Do I have something that could be a problem? Thanks
Mike

Michael, it sounds like you are leaving the clutch disengaged when the T is sitting. When you stop it, leave the lever forward, and it will squeeze the oil out of the clutch discs, and make for less drag when starting.
Bob

If it happens on occassion, it is probably carb ice. Do you have an air oven preceding the air before it enters the carb. If not I suggest you get one.
Carb ice occurs not at freezing temps but at about 50-80 degrees if it is humid. Sometimes the ice will drip when you shut off the engine. Sometimes the carb will actually have frost on the exterior near the strangle tube or venturi.
Noel

Butch,

Although I do not have enough information to make a firm diagnosis, I have three thoughts on possible causes for your problem.

1) The closest experience I have had to your description was on the San Diego Speedster Run last October. My speedster started the run fine but about half way into the first leg seemed like it was losing power. When I had to climb some small hills it had definitely lost major power. It felt like carburetor to me. I stopped and opened the bowl drain on my NH. All of my power came back. This happened again on leg two. I removed the NH fuel bowl and dumped some fuel onto the ground for about 5 seconds. I did not have any problems after or since. I believe I had a fuel contamination (water?) problem.

2) Although your symptoms do not match exactly what I have seen on several cars you may have a partially (not as bad as I have seen) plugged sediment bowl on your fuel tank. Crud that is or was in the tank can plug the fuel supply hole at the shut off valve. This usually causes the car to completely die after a distance though. Less likely is it could also be the filter screen in the sediment bowl or any other part of the fuel supply system.

3) About 10 years ago a fellow club member had his car loose power after a few miles on three tours in a row. He stated after the third tour he had finally found the problem. He stated that he had found a crack in the intake manifold and that it was opening up when the car warmed up. He never had a problem after that.

One last note. There is one very easy modification you can make to most 09 to 25 T’s that will solve many of your potential fuel problems. I do not know if or how it would work on a 26/27 with a dash fuel tank. It was published more than once years ago in the Vintage Ford Tinkerin Tips and in the MTFCA Carburetor manual. You add a 60's VW fuel tank filter screen at the fuel outlet of the fuel tank.

IT WORKS and it is invisible!!!!!!!!!

I WILL NOT build a car with out installing this $6 filter even if I am using a brand new fuel tank.

Again about 10 years ago a fellow club member bought an early T with a starter engine, a fuel pump, a fuel pressure regulator, and an A Tiltison Carb. That carburetor caught fire twice because of crud in the gas tank causing the float valve to stick open and thus allowing the fuel pump to pump fuel out the carb vent hole. His fire wall is still charred from the two fires. He has not had a single fuel problem since I installed the VW filter screen at the fuel tank outlet!!!!

The original articles stated that you should cut the flange off the VW filer screen. I no longer do that. I drill the fitting that is going to screw into the bottom of the tank to accept a press fit for the flange on the VW filter screen. Myself and at least one other club member have discovered that the stuff they put in gasoline today does dissolve JB Weld. The press fit works better that even soldering.

Terry