MTFCA Forum

I think I've got this right, but then sometimes what I think is correct isn't too.

Please look this over and let me know, thanks.

Got a revision...line work, forgot a few....

Again, if you see something that is out of place, please let me know, thanks.

Your drawings are amazing! And helpful...

Glad you found them useful...it is really the only reason I draw them, that and I get bored being retired and there only two remedies for that. 1) I go out and drive the T round a bit or 2) sit down and draw an assembly...the last few days its been raining...so, that leaves my other favorite thing to do...drawing.

Small revision, on the eccentric plate, changed part number from 3987 (as is the eccentric itself) to 3988.

Mart, you had drawn two images of the Holley Vaporizer carb some time ago. I grabbed and studied them so much I can almost tell how one works.
My hand cranked TT sure starts nice on 3 pulls so you are providing a needed service to those of us willing to study and learn.
Love seeing ALL of your drawings, they are a blessing!
These fan images are great!

Perhaps I missed it, but there was an earlier version that had a worm and screw to rotate the eccentric. I think there was breakage problems with it and Ford came out with this second design that is shown in your drawing that was more robust in terms of less breakage.

Like others have said, you do nice work and help us better understand the inner workings of the Model T Ford.

Arnie

Here is the early 1926 version, was done first.


viewtopic.php?f=2&t=3352

Breakage, like this ???

Thank you Martynn for your super nice and detailed drawings. Invaluable.

VERY specific question here, if you don't use an original pulley, but instead use Lang's part #3962BBN(machined aluminum pulley with two sealed ball bearings that obviously don't require oiling or greasing), I can see where you would NOT need part #3983(felt), but do you still need part #3982(fan shaft cap) that fits between the fan eccentric backing plate and the modern pulley just as a spacer to KEEP ALIGNMENT for the belt between that pulley and the crankshaft pulley??? The reason I ask this is, I am having problems with my fan belt "running off" the two pulleys and BOTH pulleys and belt are brand new!!! I have tried using fan shaft cap(part# 3982 - to me a "spacer") and not using it, with the belt "riding off" the pulleys both ways. Also tried adjusting the belt tighter and then looser, with NO luck either way. What am I missing??? Hope someone can give a specific answer to help me?!! Much Thanks!!! Walt Wise

Walt

the product you bought is well made, however I have found in nearly every case, that the pully must have a custom spacer made and placed behind it to bring it forward enough to be in line with the crank pully. Sometimes just a washer's thickness...sometimes more...FWIW. Now, that said, I have never worked this issue with '26-27, so if this is your case, I may be off the mark.

Belts will not track for one or more of the following 3 reasons:
one or both pullys lack proper crown (often the case with fans, but not for you now, I assume)
pullys are not in rough alignment fore/aft
fan bearing bolt tilts "down" (found fairly often)

Walt

We have a similar issue. We are using 3962BNN with the sealed bearings. The part came with a spacer which we assume belongs between the pulley and the eccentric backing plate. The assembly still had about 1/16" play in it, so we placed the felt(3983) inside the shaft cap (3982), and placed that between the eccentric and the spacer. We also did not use a gasket between the fan and the pulley since the kit did not come with one. Just wondering if we did the correct assembly?

Here is an update on my fan pulley/shaft issue. First, one of my sealed bearings went bad and had to be replaced. Why, I assume just a dud bearing? Anyway…it made the most awful “metal” noise that initially I thought was coming internally from the engine block – thankfully it wasn’t, just a bad bearing in an all but new pulley.

So yesterday before it got miserably hot, with a new sealed bearing in the pulley, I installed it back on my 26 Coupe. One thing Mr. Conger said in his post reply, “fan bearing bolt tilts "down" (found fairly often)” struck a chord with me to be cognoscente when attempting to tighten the fan shaft nut, really needing three hands(one for the wrench to tighten the nut, one for the wrench to hold the shaft end from turning, and the that third hand to lightly lift up on the fan/pulley area to keep it from “tilting down”. Well…so far, the fan belt is “tracking” just fine, although I just throttled the car up/down in the garage, since it was too hot at that point to get it out. Additionally, I had the same issue as posted by Mr. Hjortnaes, I had about 1/16th inch play of the pulley on the shaft, but it didn’t seem to matter thus far, so I didn’t attempt to add part 3982/3983 or a washer instead. I guess for now, the jury is still out…

Thanks for the replies, since I did sort of hijack this post with a question of my own…Walt Wise