Crank shaft pulley

S

Sailormike

Member
Good morning Guys,

I have a question about a problem with a crank shaft pulley.
I bought my 29' Coupe shortly after i got it when i was paining the motor I discovered that I could turn the fan and crank pulley almost 1/2 a revolution before it would engage the crank. Yesterday it broke and now the pulley does not turn with the crank at all do you think I sheared the key or did the funny bushing that hooks to the timing gear snap or did the key snap. I am trying to determine if i should tear into it now or wait till after the national show coming up.
 
Mike,
It sounds as if a chunk broke off the back end of the pulley. The keyway in the back is very shallow.
Remove the nut, pull the pulley forward, cut it off with a Saws-All & remove it. Then replace it with a 2 piece one, which screws together with a L/H thread. It's an EASY JOB.
Bill W.
 
Don't forget the cardboard to protect the radiator while you're working on the pulley.
 
Do you have a one piece original pulley, or do you have an aftermarket two piece pulley?

Two of my engines have the 2 piece pulley and here's the one I'm working on right now. Someone forced the pulley sleeve all the way on without lining up the notch to the key. You can see it forced a new slot into the aluminum sleeve, and also cracked the sleeve. I saw the same thing happen on a friend's engine I worked on 3 years ago, but his was the original cast iron, and it broke a chunk out.
 

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Job best done with the radiator removed. Removing the broken pulley/hub may require the use of a "puller" or even vice-grips and a prybar.

The original pulley was one piece. For a while there were two piece pulleys which were a sort of "square drive" held together by the pulley retaining bolt (the one with the ratchet for the hand crank.) The symptoms you describe may be failed spokes on the pulley, or the square has become "misaligned", OR you may have sheared the key-end in the motor which the pulley hub engages (the pulley retaining bolt only holds the pulley in place - it does not prevent the two parts from relative motion - this duty falls to the camshaft gear key.)

Were it mine I would keep it "original" and replace the pulley with a one piece. But there are much improved "screw together" pulleys available now which reportedly can be done with the radiator in place - possible but for removal of the old parts which is a challenge even with the radiator removed.

With the old pulley removed, you'll have to locate the key, align the new pulley slot with the key, enter it into the block using your hand and the crank as your alignment guide. As the new hub enters the block, you'll likely need to give it a push or a gentle thump with a mallet to compress the seal ahead of the hub and allow the hub to seat. Not rocket science and the way the original motors were assembled. (and why the hub has a slight taper at the inboard end to ramp into that seal.)

Hope this helps - been there done that.

Joe K
 
Your pulley is broken and probably the two rope seals are torn up too.
You don't have to remove the pan to put the new pulley and seals on.
 
We reviewed the engine pulleys several years ago and found the two piece available back then were not correct and did not work well. I think Snyder's started making a correct two piece now and they have a correct one piece, which is the one we like to use.
 
tbirdtbird said:
Tom, some ppl are just so talented!!!!!!
Click to expand...

It's hard to imagine that they could have forced a new slot to be pushed into the aluminum sleeve and not know they did something wrong.
I think wrenches will now have to come with a 3 word instruction sheet. "USE COMMON SENSE"
 
Tom Wesenberg said:
It's hard to imagine that they could have forced a new slot to be pushed into the aluminum sleeve and not know they did something wrong.
I think wrenches will now have to come with a 3 word instruction sheet. "USE COMMON SENSE"
Click to expand...






If sense were common, everyone would have some. :cool:
 
In disassembling another engine the other day I ran across this pulley. Never seen this before. The sleeve is threaded into the pulley.
 

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kenparker said:
In disassembling another engine the other day I ran across this pulley. Never seen this before. The sleeve is threaded into the pulley.
Click to expand...

That the newest design iteration for the two part "removable" pulley.

The concept is great - gives room for installation with the radiator in place - but totally ignores the dimensonal challenge to remove a potentially rusted in place broken hub, OR a rusted in place thread held center core left after the spokes are busted out.

The only time I've ever broken a front pulley was back in the day before I had all the tools (toys) necessary for a safe lift. The engine tends to be "nose heavy" without the transmission or two leg lift.

Joe K
 
"That the newest design iteration for the two part "removable" pulley. "

Not sure of that.
It may be an older design. else from a vendor that many on here prefer not to use.

Snyder's sells the notched type and has for quite a while. I have serviced one car with the threaded design and had no trouble with it

lifting from any type of front pulley may not be the best idea
 
kenparker said:
In disassembling another engine the other day I ran across this pulley. Never seen this before. The sleeve is threaded into the pulley.
Click to expand...
Ken,
This is the one I was referring to in post #2. When in place, it looks "original". I've used them on BOTH my cars.
Bill W.
 
Thank you everyone for the input I took the old Pulley off the car tonight thank goodness i had just enough room to wiggle a socket on the ratchet nut and get it off. I will take a picture of what i found tomorrow the aluminum piece between the pulley and the gear was trashed. new pulley is on the way
 
The Screw together pulley pictured above came off an engine in a Tudor that had been sitting in an abandoned garage/barn for the last 35 years. Definitely not a new itineration. A hot rod friend wanted the body - sold me the chassi
 
I found that the cast pulleys are more likely to break than a steel one . I broke 2 cast pulleys & never had trouble with the 2 piece steel one
 
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