1912 Fan Belt problems !!

[AndreFordT]

Sometime ago I started working on a 1912 engine that was hard to start.

The mechanic before me cut off the front of the oil pan and added a kind of flywheel to the crankshaft pulley with an electric starter on it.
No help the engine didn't start and ass it started up the car was hard to drive because there was no front support on the engine and the front axle was everywhere but not where it should be.

All that came at home just before CORONA.
I replaced the oilpan, put a new 3" pulley on the crankshaft and build a new fan on the engine with a used bracket from Lang shaft T-3966 and the bracket bolt T-3968 were also new.
The engine was running great till a few weeks ago the 23" fan belt run off the and distroyed it self.
Last Saturdays I changed the shaft bolt , the bracket bolt, the bracket and the belt but I am not sure about the result. The engine for 30 minutes but I could drive the car because it was nearly dark and raining.

In the attachement and next post you will find a few photos of the problems.

Thanks for trying to help.
Andre
Belgium

[AndreFordT]

The repair.
Andre
Belgium

[Kaiser]

Hi André;
There seems to be an alignment problem, the pulleys on the crank and the fan are both "barrel"formed to ensure the belt runs on the center of both pulleys even if there is a slight alignment difference, but if it is too much that won't help and the belt will seek the highest spot, which in this case is the rim of the fan pulley and will run off or when one of those forks is installed as in your case it will not be able to run off and destroy itself.
Be sure to check the mounting of the fan bracket, that might be the cause of the belt not running true,
Good luck, Leo

[D Stroud]

What Leo said. Something is off in the alignment, maybe the fan bracket is bent? It doesn't take much misalignment to make a flat belt run off center. Dave

[Bill Dizer]

You might try turning the belt inside out and running the flat side on the pulleys, not the multi groves, and not running it too tight.

[Allan]

If the fan belt runs off to the front it indicates that the fan shaft is misaligned downwards to the front. To correct this problem I have removed the arm and clamped it in a vice at the approximate angle that it is set at in the car. With,a bolt tightened in the eye, a large crescent wrench can be used to bend the arm upwards, taking care not to twist it. It may take several adjustments to achieve the required result. If/when the alignment is correct, the device used to help keep it on track will be redundant.
Hope this helps,
Allan from down under.

[D Stroud]

What Allan said! Dave

[Mark Nunn]

Andre said the engine was great until a few weeks ago. I doubt that the arm bent during use. I would look at the bushing in the fan pulley. A worn bushing will cause misalignment.

[TXGOAT2]

To try to add a starter to a Model T that way is utter madness. Perhaps the engine was in stationary use or in a boat when the adaption was made. (?) The T engine has to be mounted properly, since it has a major role in locating both the front and rear axles. Excessive looseness in engine mounting will destroy the car's stability on the road and will affect stability of the throttle and spark controls. The engine has to be installed the way Ford intended.

[AndreFordT]

First of all thanks for the sugestions.

Just some remarks.
The fan is made with a new roller bearing pulley so no wear there.
As the car came to me I tried to make it original again or at least as original as I could find the needed parts.
The oilpan is a later one.
The crank shaft pulley, the fan and roller bearing pulley, the bracket bolt, the fan shaft and the 23" belt were new, the fan bracket is new since last Saturday. I replaced als the fan belt.
As the owner should have an electric starter on his car, I looked for a right hand drive hoghead with starter spaces and added a 1919 model T starter to the car.
With all this the engine had a total overhaul too.
All this was not cheap and I should like to find a sollution for the belt.
If the repairs, I did last Saturday, don't help, I will try to heat up the cast iron bracket and bent it a little to the back and see what will happen.

I was also wondering if the old belt wasn't to tight so it bent the bracket and the belt started running to the front.


Andre
Belgium

[TXGOAT2]

I'd check the alignment of the pulleys and see that the fan shaft and crankshaft are lined up parallel. If they are, it's possible the fan belt iteslf had a problem, like a broken cord or some other defect that caused it to run off the pulleys. Be sure the crank pulley is secured to the crankshaft properly.

[Allan]

Andre, original fan arms are forged, rather than cast. They can take bending cold. If yours is a cast repop then heat would be a good idea, but bending cast iron is always fought with problems.

Allan from down under.

[Norman Kling]

In addition to checking the pulleys, also don't tighten the belt too tight. It should hold your finger resting on the fan with the weight of your arm. But if anything heavier, the fan should slip. If it is too tight, if it begins to move either forward or aft on the pulley, it could stretch the edge of the belt which would cause it to run off. Normally, the high center of the pulleys will keep the belt centered on the pulley unless the edge begins to stretch, which would cause the belt to run off.
Norm