Power steering pump pulley mystery!!!

[idrivemopar]

A few months ago, I pulled off the power steering pump pulley from my old pump and to use a pulley puller as it was pressed on. Nothing unusual here with this process.

Now the mystery I went to put the pulley back on a new pump, and it just slides right on, no need to press it, and its not a keyed shaft with the pulley held on with a bolt. I thought maybe I had a defective pump and the shaft diameter was wrong. I went a got my old pump out and it has the same problem, slides right on with no need to press.

What's the deal, how did the inner diameter change, was their a sleeve inside the pulley? Could the fact that I had the pulley powder coated have caused it to stretch and it no longer fits?

Any idea what happened here?

 

[bm02tj]

Possible they sand blasted it to much but heating and cooling for powder coat would not do that

or a young helper over did it and they buffed it smooth in the bore

 

[idrivemopar]

No, the only blasting on it was a very light bead blast just to get the powder coating to stick, the inside diameter is still very smooth, but the gap around the pump shaft is about 1/32 of an inch total. No young helpers there, its a father and son team, and they have been doing it for many years. I am baffled!

 

[MarPar]

do you have any pics of said pump and pulley?

 

[70redbee]

Are you sure you got the same pulley back from the powder coater that you gave him? Has to be a different pulley if it doesn't fit the pump it came off of.
THE TWILIGHT ZONE

 

[idrivemopar]

Yes, it is the same pulley that I gave them. Not sure what help a picture will be, but here is one of the pump and pulley.

 

[CudaChick1968]

Very interesting ...

The only thing I can think of that may have caused the opening to elongate is they forgot to plug the center and got too much overspray in it. Then removed it with an overly aggressive grinder bit and smoothed it out (or covered up the screw up) with a few passes of crocus cloth.

When it's done right, normal powder coating processes do NOT change the composition or size of the metal. If you figure out what they did, please share!

 

[Photon440]

I think your idea that there may have been a sleeve could be right. At any rate, you might need to get one made up to fit your part.

 

[Pops1967GTX]

Question.....Is the shaft on the steering pump threaded? If so, the pulley slides on the shaft & retained by a nut.... On a Pressed on pulley...You must disassemble the pump container to support the shaft to reinstall pulley to revert damage..... Possible sleeve, but ever seen it......

 

[idrivemopar]

Nope, not threaded pulley, its a press on. My powder coater is pretty good, and they block off openings like the one on the pulley, so they don't get powder coat on the inside of surfaces, and their are no marks on the inside either for where it would have been ground out. I got a March performance pulley today, and its the right diameter however, the offset is not right to line up with my crank and water pump pulleys, so I will be calling them tomorrow to see what I can do and if I can use theirs, otherwise I will have to look for a salvage pulley.

 

[67 coronet]

http://chucker54.stores.yahoo.net/pulleys1.htmlif the one from march fit ok except for offset then there must have been a bronze bushing someone machined into your pulley a while back that fell out durring one of the processes that you had done.take a look at mancini racing,they have both aluminum and steel pulleys available.

 

[idrivemopar]

Nope, Mancini does not have them, combing the salvage yards now as the March Performance pulley is correct diameter, and shaft diameter, but the offset is only .45 and I need .75, so close but no cigar! If anyone finds on shown in the picture above that is used, let me know.

 

[MarPar]

Not sure what help a picture will be, but here is one of the pump and pulley.

View attachment 139013

If anyone finds one shown in the picture above that is used, let me know.

see...pics help :toothy4:

 

[idrivemopar]

Good news, found one back east, not cheap as these are hard to come by evidently.

 

[idrivemopar]

Mystery Solved!!!!

Got my "new" salvage pump in today, and when I went to pull the pulley off, I discovered the cap that sits on the end of my puller, and butts up against the pump shaft is ever so slightly larger of a diameter the pulley shaft. When I took off the original, this thing basically acted like a boring tool and bored out the original pulley diameter.

I have confirmed this was the issue why the original pulley no longer fit the pump. The cap I used on the first pulley still fits in the original but does not fit the new one, as I used a different, smaller cap on the puller this time. Hopefully that makes sense and mystery solved!!!!

 

[bm02tj]

That would answer the question

good catch before wrecking the new one

 

[MarPar]

sweeeet!!!

dont'cha love those kinda moments?? :hello2:

and of course...it's always after the fact!!