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Its been 4 years since I did a. Cummins swap on '89 F350. I used the 2nd gen reman'd vacuum pump on my '89 Cummins. I was towing my boat a couple months ago and had to make a hard turn to the left and heard a pop and lost power steering. I pulled it apart and broke the tangs off the vacuum pump drive. I bought a Dorman one (only one available?) and was pulling out of a driveway and was turning sharp to the right and heard the same pop. I have around 300 miles since installing it. I'm pretty certain I broke it again. Are these common to break? I average around 3k miles a year on this truck. I've thought about doing away with it and going to hydroboost since hydroboost was in my future plans anyway. All of my hvac controls/cruise use vacuum and I'd have to have some kind of vacuum pump.

Any idea what's going on?
 

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PS bracket - side view.JPG

Do you have a bracket from the pump to the engine block?

This is a homemade bracket (side-view) that attaches to the bolts that support the VE pump.

129149

And the bottom view. Started with a scrap of angle steel and cut & drilled to fit. Over 70+K miles and 37 states so far.

Russ
 

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Discussion Starter #3
Do you have a bracket from the pump to the engine block?

This is a homemade bracket (side-view) that attaches to the bolts that support the VE pump.


And the bottom view. Started with a scrap of angle steel and cut & drilled to fit. Over 70+K miles and 37 states so far.

Russ
Thanks for the response. Yes I do have a bracket. It's a homemade one using a piece of angle iron. Just like the one you have pictured. I believe the one I just replaced has a bad power steering pump. I bought a reman'd one and realized I broke my vacuum pump. Then decided to run the new one. Which ultimately failed. I will swap my old working one on tomorrow and see what happens. Thanks!
 
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Both failed on a hard lock would suggest a power steering pump problem. The relief valve should dump pressure when it is deadheaded in a full lock situation.
Are the holes in the bracket larger enough the brackets sits properly against the pump and block without placing tension on the pump when the bolts are tightened?
Cheers Steve
 

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Discussion Starter #5
Both failed on a hard lock would suggest a power steering pump problem. The relief valve should dump pressure when it is deadheaded in a full lock situation.
Are the holes in the bracket larger enough the brackets sits properly against the pump and block without placing tension on the pump when the bolts are tightened?
Cheers Steve
Thanks! I slapped my old pump on and it works fine now. I've heard of the ears on the vacuum pump drive breaking off due to age/wear? I figured that's what happened to the 2nd one but it was fine when I pulled off the power steering pump.

The bracket that I made isn't pulling the pumps in either direction when bolted. Its tight against the block and power steering pump. All the holes that I drilled are larger and allow for movement/adjustment.
 

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Wabco vacuum pumps and Saginaw steering pumps are the best that has ever been made. They usually outlast the vehicles they are in.
 

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Wabco vacuum pumps and Saginaw steering pumps are the best that has ever been made. They usually outlast the vehicles they are in.
Tell that to this poor guy...
129165
 

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That's really strange. Did the broken off drive lugs have wear on them or were they broken clean off?

I'm with the other guy thinking somehow the pump deadheaded. They have a relief built into the pump though, so not really possible. So strange.
 
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