Replace crankshaft pully

Ltmoeller

Junior Member
The front of my crankshaft pully is completely broken off.I can get the nut off.Is there any way to get the remainder of the one piece pully shaft off without lifting the motor?I plan to replace it with a two piece pully.1930 sport coupe.
Thanks Tom
 
The problem with this is likely RUST between the crank and the pulley hub.

I think you'll likely have to drop both oil pan and the timing cover to expose the portion of the hub which is normally covered by these two parts.

On removing the pan and cover you'll find the "inner edge" of the pulley hub and you'll note that it is "tapered" at a 45 degree angle. Problem being is that this taper prevents you from using an ordinary 3 finger puller as they slip off the angle.

The taper is there to allow the pulley/hub on assembly to force its way between the soft seals present at this location. Many modern replacement hubs don't have this taper or the 45 is modified into "rounded over" for similar compressive effect.

So you have to somehow "grab" this tapered edge and then "pull" the hub off "puller style."

Actually a pair of vise-grips and a large C-clamp can do this. Clamp the vise-grip around and then use the c-clamp between the grips and the end of the crank.

Be careful as you do this as things have a tendency to go "sproing" and you could end up with it in your kisser.

Modest heat with a torch may expand the hub enough. Tapping on the backside of the vise-grips may be enough to break the bond.

And of course PB-Blaster applied liberally.

There is a "Keyslot locator" on that innermost part of the hub. This engages with the key for the crank timing gear to positively locate the pulley relative to the crank. AND prevents you from "turning" the hub as an effort at loosening it. You have to come off "straight out" with that pulley hub.

Joe K
 
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Yes, with the one-piece crankshaft pulley, you will need to raise the front of the motor quite a bit for the pulley to clear the front crossmember. It was a dumb design for servicing because of this. Apparently the Ford engineers thought this cast iron piece would never break or need to be replaced. WRONG!! Cast iron breaks easier than china crockery. :) I had to do this unpleasant and invasive task just last week to replace a broken pulley rim.
It is advisable to remove one rear motor mount bolt from each side and radically loosen the remaining two so that when you jack up the front of the engine, the engine will tilt and will not stress the flywheel housing and crack it. I have also heard of the bending crankshaft breaking off the Babbitt thrust on the rear main bearing because these bolts had not been removed/loosened. The whole job is a great deal easier with the radiator removed. I don't think that you can do it without removing the radiator because of the close quarters. Resist the temptation of installing a two-piece pulley! The two snouts will knock against each other under torque and make a banging noise that will drive you nuts. In the last couple months I have removed two of these two-piece pulleys and neither one was solidly together. One had a broken rim, like yours. Under normal circumstances, a quality spoked one-piece pulley should last longer than you will!
Marshall
 
Yes, with the one-piece crankshaft pulley, you will need to raise the front of the motor quite a bit for the pulley to clear the front crossmember. It was a dumb design for servicing because of this. Apparently the Ford engineers thought this cast iron piece would never break or need to be replaced. WRONG!! Cast iron breaks easier than china crockery. :) I had to do this unpleasant and invasive task just last week to replace a broken pulley rim.
It is advisable to remove one rear motor mount bolt from each side and radically loosen the remaining two so that when you jack up the front of the engine, the engine will tilt and will not stress the flywheel housing and crack it. I have also heard of the bending crankshaft breaking off the Babbitt thrust on the rear main bearing because these bolts had not been removed/loosened. The whole job is a great deal easier with the radiator removed. I don't think that you can do it without removing the radiator because of the close quarters. Resist the temptation of installing a two-piece pulley! The two snouts will knock against each other under torque and make a banging noise that will drive you nuts. In the last couple months I have removed two of these two-piece pulleys and neither one was solidly together. One had a broken rim, like yours. Under normal circumstances, a quality spoked one-piece pulley should last longer than you will!
Marshall
What Marshall said, especially with regard to the undesirability of the two-piece pulley. The interface between the two is another possible failure point (voice of experience speaking...).
 
In the Les Andrews book he makes it look very easy to change this pully.From everything I’ve read and the comments here it’s more entailed than what’s in the book.I hope I can get the pully shaft out without to much work.
 
One thought I had as I was writing earlier: use a three jaw puller from Harbor Freight - but "encircle" the three jaws with a large stainless band clamp - to constrain them to stay below the inner edge of the pulley hub.

https://www.harborfreight.com/3-jaw-puller-set-3-piece-63953.html

Its a different pulling configuration, but sometimes you have to get ingenious and do "different."

Most today assemble the engine crank/pulley first, then apply timing gear cover/oil pan "afterwards." Pushing down (and up) to compress the soft packing.

In the day, the engine was assembled including pan and cover and the pulley was "applied" afterwards by driving it into place from the front of the engine - and the taper "eases" the penetration into the engine and compresses the packing in the process.

The packing MAY be your largest constraint in removal of the hub. Removal of at least the timing cover may give you space to insert a large pry bar and "pry" the hub from the crank.

Generous PB Blaster. Then use a 12oz ball pein and gently "tap" around the hub to compress and potentially loosen the rust.


Joe K
 
In the Les Andrews book he makes it look very easy to change this pully.From everything I’ve read and the comments here it’s more entailed than what’s in the book.I hope I can get the pully shaft out without to much work.
Like quite a few things on a Model A, it really is pretty straightforward - unless it isn’t.
 
While it wouldn't be my 1st choice if I could not get a puller to grip it You could crack that hub with a sharp chisel Cast iron is quite brittle If you cracked ITIT should slide right off.
 
While it wouldn't be my 1st choice if I could not get a puller to grip it You could crack that hub with a sharp chisel Cast iron is quite brittle If you cracked ITIT should slide right off.


Could one score the hub front to back with a small air grinder to weaken it and then crack it with a sharp chisel? Seems like this would cause less stress on the crankshaft.
 
I got the radiator out and the pulley nut came off easy and the pulley slid loose very easy.So now do I remove the two rear motor mount bolts then the front mount bolts?Looks like if I could remove the center spring hanger I’d have much more room but I’m not sure about doing that.
Tom
 
I had a similar problem. I took a hammer to the pulley and it broke apart quite easily. With just the shaft part of the pulley left it came off without moving the engine. I then installed a two piece pulley.


bob
 
Bob,that is exactly what I did.I bought the one piece because many people were negative about them but I talk to Snyders and they assured me that the fitment was much better than the ones in the past so I went with the two piece.
 
I HOPE they are better now! The two-piece crankshaft pulleys were garbage for years. The two halves might have fit together when first installed, but over time and after thousands of torque pullings against each other, the two notches wore away and became loose = knocking. In the past three months I have removed two of these older two-piece pulleys. One had a broken front rim. BOTH were loose and knocking against each other as the engines ran. Once removed, in your hand you could rock both halves back and forth with a LOT of play between them. The ratchet nut cannot keep the two halves from moving under torque forever.
I understand someone was making two-piece pulleys that screwed together so that as the crankshaft turned, the two halves tightened against each other. Now, THAT design I like. No one is arguing that a two-piece pulley saves a ton of effort to remove and replace compared to a one-piece pulley. I just don't like the potential for yet another knocking noise, this one being completely avoidable.
How does Snyder's explain that THIS iteration of their two-piece pulley is improved? Too many crappy two-piece pulley removals later, I am skeptical.
Marshall
 
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