Sorry for the long post, but I am at my whits end.

The belt walks up to the front edge of the crank pulley as soon as I start the engine, but doesn't walk completly off while ideling. Haven't driven it yet to see if it will stay that way.

A few weeks ago the previous 4-month old belt (from Checker Auto) got slightly chewed up on the front edge. I found this after hearing a 2-second flapping noise while making a right turn. Replaced the belt and tensioner pulley (from Checker) and all was good.

Replaced a leaking power steering pump yesterday with one from Auto Zone. What a pain that was!

Anyways-after all was put back together, I noticed the belt problem while checking for leaks.

Thought it would be the tensioner-so I replaced it with one from the Zone. Same thing happens.

So I decided to pull the PS pulley out a smidge since it was flush with the end of the shaft. Ran the engine and still the same thing!

Any thoughts? Crank dampner is original (155K). The crank pulley has a slight ridge on it towards the front about a sixteenth of an inch before the edge.

The engine does have a slight vibration while running at all rpms.

Thanks, Ed

 

What year of truck?

Try checking alignment of all the pulleys by putting a straight-edge across the face of each one to see that they align with each other.

I've a narrow 'ridge' bevel on the crank pulley of my '78.

 

I had a belt that walked last spring. Turned out it was from my water pump. The bearings had gone allowing the pulley to wobble and cause the belt to wander.

 

RebX, it's a 91 F50, 302 and M5OD trans. Will try to find a straight edge and check pulley allignment.

sicbpguy, how noticeable was the wobble on your water pump pulley? Mine doesn't seem to wobble. Any other symptoms of the pump going bad that will allow the pulley to cause my problem?

Could it be a deffective belt? It's only been on the truck for a few weeks. The belt flluters as it leaves the crank pulley only. It doesn't walk completely off while the engine is running (about a minute of ideling).

Any other ideas?

Thanks, Ed

 

Once the belt had moved and caused me to look at things, I noticed that the water pump was pretty loose. I was able to wobble the pulley back and forth with my hands. Make sure to check all of your pulleys and good luck

 

Well, worked on the problem again after reading the post from sicbpguy and RexB, along with info from a mechanic with 10-plus years of experience. This time I took off the fan and shroud to get easier access to the front of the engine.

Checked all pulleys for wear and looseness and all are in good shape.

Put a 12-inch steel ruler against the crank and PS pulley and found that the PS pump pulley is too far forward about 1/32-1/16 (not sure about the exact measurement). The PS pulley is flush with the PS pump shaft. I made sure of that buy using the Auto Zone pulley installer tool. It only allows me to press the pulley flush with the shaft. I cranked it so much that the grade-8 bolt stretched and will need to be replaced.

I looked at the drawing of the tool in the factory service manual and it is different from the one I got from the Zone. The Rotunda tool by design seems to allow the pulley to be pressed further into the shaft, the Zone's tool has a flat face (part that pushes against the pulley). The drawing of the Rotunda tool even shows that the bolt has a tapered or conical part that fits the taper of the shaft. And the face has a raised area that, I assume, would allow enough clearance for the tool to slide past the end of the shaft.

Do I have the wrong installation tool? Is the pump shaft too long? I really don't want to take that darn pump off again!

Anyone out there ever run into this problem with reman PS pumps?

Ed

 

Whew! Stretched a Grade 8 bolt by hand! You're too strong and glad the grade 5's on my dozer blade don't do that

Anywho, here's the installer for 91 Ford PS pumps- how does it compare with what you're using?

 

Well it probably wasn't a grade 8 bolt--it was probably a stretch when said that! I know for sure that I striped the threads on the bolt though. I used my 24 inch serpentine belt remover bar and two wrenches locked end-to-end for more leverage. I kept turning the installer tool, but the pulley never went pass flush with the shaft. I decided to stop turning at that point since I didn't want to add to my woes should the bolt have snaped off.

The link to the installer is of the same type I used on my pump. If you look further down the page you will notice the other type of installer tool that I think I need. The Ford part number shown is the same as what is in the Ford service manual. I may just have to order it and hopefully get her back on the road.

 

That's a bunch of wrenchin' --Breaker Bars Forever! Smooth lookin' truck you have there Ed, nice work. Check another truck, at a dealer maybe, look at a stock install to verify the pulleyposition?

 

Thanks for the complement RexB. I've been checking out trucks when I can as they come in at my place of work. So far most have the pulley slightly past the end of the shaft.

The old pump shaft moved in and out a little more than the replacement pump's shaft. Wonder if it supposed to be that tight when new? Mechanic said that some in and out play is normal.

 

Well--finally got it straightened out!

Went and got a pulley kit from Harbor Freight and tried to push the pulley further inward, but the darn design failed completly. The installer kept comming loose instead of pushing the pulley in.

Went back to the Zone (different store this time) and rented the same type of installer, but this time I used the washer (from the HF kit). Placed it between the installer and the pulley, gave it a few turns with the same cheater bar set up, and walah! the pulley moved in the same thickness as the washer.

FYI: the washer ID is about the same as the OD of the shaft. And the OD of the washer is about the same as the OD of the pulley bushing. So I had to try to keep the washer lined up with the bushing until it was snug against the pulley.

Put everything back together, cranked up the motor, and the belt stayed in place. The pulley is about a 32nd of inch too far in now, which I may, or may not fix latter.

Now--on to the next repair job!

Ed

 

That's good news Ed, all that cussing worked and "on the road again"!

 

i think thats why my belt is walking off glad i foudn this post, it appears after close looking that my power steering pulley that is also flush to the shaft is like 1 grove outward so im gonan rent that tool thanks!