MTFCA Forum

Previousely installed a leather Ford script fan belt on my 1915 War Wagon that has a 27 engine in it. So the fan parts are a little mismatched to fit the low radiator.
I had to repair the curved fan bracket that got bent out of shape due to a leather fan belt getting wrapped around the pulley. So we took everything apart, the fan belt was toast, and straightened the bracket out and reinstalled it with the curve going down. I adjust the screw on the tab at the end on the bracket to the lowest setting and measure with a piece of string around both pullys and get 25".

The vendors sell a 25 7/8" leather fan belt that I presume I can get to work with adjustment. But no vendor sells a Ford script belt shorter than 27". So I wonder how I had a Ford script belt on before. It's only a few years old. It got me wondering if the curved in the bracket should be pointing up and that may accommodate a longer belt.

Confused yet? I am. Curve up or down.

Robert

it goes "down". Even without asking, I'd bet you'd quickly see the fan will hit your radiator if the bracket was "up"

And if you need a 25" belt, you do indeed have a bunch of mismatched parts. Somewhere between the crankshaft pully, which may be a later larger one, to the fan pully, which may be a matching/larger/later one, you have the curse of "all T's are the same".

Personally, I'd buy an endless belt of the correct size from one of the suppliers (from the size you have deduced) and enjoy the heck out of the thing. You may eventually want to divorce these parts and marry up the correct ones in the future...and then you'll need a 23" belt (and forget about "FORD" Script).

Another ‘Franken-T’ huh ? What Scott said - “down”. Just be sure whatever fan and pulley you use clears the crank pulley and bottom of top tank. An early riveted blade fan will. A later 4 screw fan probably won’t.

Robert,

Keep in mind that the diameter of fan hub and the crank belt pulleys were different between 1915 and 1927, so if using a 1915 fan hub with 1927 crank pulley it will more than likely result in a nonstandard belt sizing.

Larger later pulleys need to be matched together. And smaller earlier pulleys also need to be matched together. Mis-matching the pulleys will result in a fan speed that could either make the fan totally pointless by running too slow (the fan is nearly pointless anyway), or a too-fast fan that is about four times more likely to break and ruin your radiator.

Thanks to all for verifying that the bracket is installed correctly. We are headed to NAPA to have them research a flat 25" x 1 1/8" belt to get us through the next car show. Without the fan belt, I crack started the T about 40 times and ran it for a few minutes while explaining the magneto and fuel pump and water pump abscences. 94 degree heat and static display, our motometer was up in the high summer range all day. So I'd like some sort of fan for the same display opportunity coming up this weekend.

Then during the winter, I can pull the radiator and measure all my pulleys and get a more correct set up. I've probably got a 27 lower pulley but my upper pully may be late as well and my ratio is OK, but my fan belt length is not "standard" due to the low radiator and hood issue. I remember I needed a different water hose connection to line up with the radiator correctly and a different fan bracket and fan belt adjustment set up.

My fan bushing pilot shaft bolt on the 15 takes a grease cup on the end. The one that was on the 27 speedster engine when I got it has a castle nut and no grease cup, like a sealed bearing set up.

So I may have some options on the actual fan pulley to match the lower crankcase pully.. If I have the correct for the engine larger lower crankcase pulley, does anyone have the correct circumference measurement for the fan pulley that would be correct to provide optimum fan blade speed? The two options I have may be identical, or I may have a better way to go that might also get me into a more "standard" belt length.

Again, thanks to all.

Robert, I’ve been driving Model T s since ‘66 and don’t claim to be an expert but I learned many years ago from high mileage experts that the only time you need a fan is during a parade in the South during summer. This is assuming a clean engine in the coolant chambers and an excellent radiator. That said, I run fans on all my Model T s. I’d recommend fans be used of course but make sure the blades clear top tank, radiator and crank pulley. It’d just be icing in the cake if you can be able to use a vendor belt.

Ordered leather belt 25 7/8 from Lang's today. Delivery In two days. Presume I have enough adjustment in my adjustment bolt to get it to stay on. I'll dress the inside of the belt with one of the suggestions made previousely and just monitor the tension frequently. Lesson learned is that if I don't go around and feel evry nut and bolt and grease cap, etc., something will sneak up on me.

I don't do the touring stuff so don't have the "break down" mentality that those seem to have and are prepared for every emergency. So I need to do more preventative maintainance.

Thanks to all.

PS
My guy a ACE looked up the endless belt number that one of the vendors shows in his photo and it turns out they are vacuum cleaner belts. I can just see the sign posted on my T that "some parts are supplied by Acme vacuum cleaner and sewing machine rapair" That's why I went with the leather belt..

That would have to be ahellufavacuum

for real information on the designed specs of Gates belts for early cars: https://www.gates.com/us/en/power-trans ... 000-000000

Got the 25 7/8" leather fan belt from Lang's in super short time and put everything together. Snugged up the belt with just enough tension to take the stiffness out of the belt and still turn the fan. Cotter pin in fan bracket bolt and had to remove the crank knuckle to get the stiff belt on, so new cotter pin down there as well.
Big car show tomorrow with lots of hand crank starts, so I'll check tension again when we get home.

Thanks to all.