Ok I read all the threads on water pumps but I was concerned about the Christmas parade (In Summer here) and boiling . So I thought what the heck and installed a pump for the parade (It still Boiled !) I haven't got around to removing it yet and in fact haven't driven the car for a few weeks. Yesterday I went for a drive and the motormeter redlined and the car boiled.A quick check showed the pump had seized up -It still turned but not by the fan belt and was very tight. The resulting drag on the fan belt from the non turning water pump pulley meant a very slow turning fan and reduced cooling -Off came the pump and into the scrap bin ! I should've listened !

Dave

Wait don't throw that pump out. People like me will need it. Might be able to sell it on trademe.

They make good wheel chocks.

Sounds like the packing nut is too tight or lack of lube to the bushings. The packing nut should be just tight enough to prevent water loss but loose enough not to bind up the shaft.

Also check your adjustment on the spark and spray needle (running too lean can over heat the motor).

Even without the fan turning it should not overheat real quick. Guys have run their T's in parades without fans with good radiators. You may have a plugged radiator or crud in the block and need the band-aid water pump to help cool the engine.
I have an Atlas brand pump (and it does move the water!) on my car with an old radiator. Using the spray needle and a slightly rich mixture along with setting the spark for the load, so far, I rarely overheat.
If the car runs hot try a richer mixture and more advance on the spark. If that does not help, time to look at the radiator.

I boiled over big time during my first parade years ago. I thought that because we were slowly going along at a idle speed that I needed to have the spark totally retarded. Advance your spark to a smooth fast idle and the motor will run cooler.

PS- Even a radiator that physically looks clean can overheat due to age. After years of expansion and contraction cycles due to heat the tubes and fins can microscopically separate where heat transfer between the fins and tubes become inefficient and over heating occurs.

Karl, one of the biggest water pump problems is that after you get the shaft nut tight enough so it don't leak water around the shaft, then the belt can't turn it.

After market radiators can have as few as two rows of cores and three are not uncommon.

Most new radiators will have four or five rows of cores and hold almost another U. S. gallon of water.

A new radiator is the best investment you can make for a Model T.

Then too, 80 year old brass is far too brittle and often cracks when trying to just install a new core.

One of the biggest water pump problems is that instead of using a little grease on the grafite rope packing behind the nut people think they need to tighten the nut when only a little grease is needed!Bud in Wheeler,Mi.

Agreed, Bud

My first parade (Memorial Day) was a comedy.

The T overheated and it stopped running because of vapor lock.

My solutions were easy.
First I rerouted the fuel line so it crossed the exhaust pipe at a 90 degree angle as far to the rear as possible (under seat tank)

Second I shut the motor off when I know that there was going to be an extended stop. People applaud because it doesn't have a starter and I crank.

Third I carry a quart squirt bottle of water that I spray on the radiator when the motor meter begins to get too high. It is amazing how quickly the temp comes down and how little water it takes. Once in awhile someone will offer to refill the bottle even though it is not needed and one guy offered the hose from his house.

I also put a wooden block in the brake handle slot so it will not go into high gear. I wait until there is a little space before engaging low and I make sure I am not slipping the band.