Crankshaft and pulley question

[jaybee47]

Starting crank pin T3040, Fan belt drive pulley T3963, Crankshaft T3030.
Does the pin have a press fit or clearance fit with the two holes in the inner hub of the fan belt drive pulley?
Does the pin have a press fit or clearance fit with the hole in the crankshaft?
Many thanks for all comments.

[BobShirleyAtlantaTx]

The pin has a clearance fit in the crankshaft. The crankshaft pulley has one clearance hole and the hole 180* to that, that is too small for the pin to go through. The pin is kept in place using a cotter pin on the big hole end on the inside of the pulley.

[DanTreace]

Better to have a transition fit into both parts. The pulley pin shouldn’t fall thru.

That pin should need outside assistance of a drift punch and mallet, to place it snugly in both the pulley and the crankshaft.

Drive it out, if needed to dissemble, sending it out the larger hole of the crank pulley. The cotter pin on the pulley pin is safe guard for a too loose or clearance fit of a worn pulley pin or worn crankshaft hole.

The hole in the crankcase front support, which is there for pulley pin removal, will let a wayward pin fall on the road!

[Norman Kling]

If properly installed with the cotter pin on the side of the pulley with the larger hole, the pin should not fall out, however, at idle it will make a knock as it moves back and forth in the crankshaft. So if you have a knock at idle, that could be the cause. I have found that laying the pin across a vise partially open and hit the pin in the center with a punch to put a slight bend in the pin will tighten it enough so it will not cause the knock.
Norm

[jaybee47]

Thank you for your replies.

The pin diameter is too small and/or the crankshaft and pulley holes are too large...am not sure which is the culprit.
Currently the pin slips entirely through the two inner hub holes of the pulley.
The pin also slips entirely through the crankshaft hole.

The pin does not slip thru the smaller hole on the outer skirt of the pulley

I was getting a knock.

As I understand from the replies, the pin fits tightly into the two holes on the inner hub of the pulley and also tightly into the crankshaft hole.
I intend to machine a new pin having the proper diameter to cause a tight fit.
I will install a cotter pin also.

Is my plan agreeable?

[Norman Kling]

Your plan is agreeable.
Norm

[DanTreace]

If your pin is old, the vendors make nice ones to Ford size.

But could be your crankshaft hole is worn too, so a custom starting pin seems like a great plan.

Remember to drill the cotter pin hole near one end. That pulley pin or starting pin as Ford named it, needs to be retained, if it should drift it can rub the fan belt. So a tight pin is the right pin.

Install the pin with cotter hole end up, into that larger hole of the crank pulley. That smaller hole in the flange of the crank pulley is for starting a drift punch to drive the pin out the bigger hole. That cotter keeps the pin out of the opening, should the starting pin ever migrate.

Use a good steel, as that solid pin takes the load of the crank handle ratchet when turning over the motor, it does need to be real strong.

[jaybee47]

Thank you...thank you to all. Now I'm going to work on it to take advantage of the 'Stay-At-Home' policy.

[RxGPoblet]

I have a follow up question. Once the pin is out is there an easy way to get the pulley off the shaft with the engine in the car? Specialty tool? Any one know the model/make of a puller that will fit nicely? I have a 15 touring with the narrow pan and my pulley appears to be wobbling and it throws the belt with great regularity. It does not feel loose on the shaft but has already been drilled once at 90 degrees to refit it so I believe its time to replace it. I purchased a new split pulley that can be squeezed down to fit the shaft in case it's worn but not sure how best to go about getting the old one off. Remove radiator and hand crank, dive pin out, and then??