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Lost my prime?

lilthom

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Nov 29, 2005
Messages
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I switched from a hydro boost set up with the Saginaw pump to the explorer pump. My Saginaw had too large of a pulley and would not build enough pressure. I crimped off all the low pressure lines to minimize loss of fluids. I had to remove the high pressure hose from the pump to change fittings for the new pump. I have full reservoir, no leaks and have cycled this thing a bunch on jack stands but still not picking up fluid. What’s the trick? I even got creative and removed the line at the hydroboost to pour fluid in the line itself. No luck.
Talk to me…
 

Broncobowsher

Total hack
Joined
Jun 4, 2002
Messages
34,835
I switched from a hydro boost set up with the Saginaw pump to the explorer pump. My Saginaw had too large of a pulley and would not build enough pressure. I crimped off all the low pressure lines to minimize loss of fluids. I had to remove the high pressure hose from the pump to change fittings for the new pump. I have full reservoir, no leaks and have cycled this thing a bunch on jack stands but still not picking up fluid. What’s the trick? I even got creative and removed the line at the hydroboost to pour fluid in the line itself. No luck.
Talk to me…

I am guessing the change in fitting messed up the relief valve, sticking it open.
 
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lilthom

lilthom

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Seriously, what’s the fix? If it’s a stuck relief valve can I unstuck it? Do I tap on the pump, the hydro boost, keep cycling it?
 
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EPB72

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lilthom

lilthom

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lilthom

lilthom

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I guess I will be ordering one today. Thanks
 

Eoth

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Mar 10, 2004
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I've been told that I am past my prime... Didn't know the fix was was as easy as ordering a valve! :cool:
 
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lilthom

lilthom

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It's been a while but I ordered and installed the Lee fitting. No difference. The pump is either not picking up the fluid or it's a bad pump. With wheels off the ground and cycling it I don't even get any bubbles in the reservoir. Some said to use a drill to prime it but I don't see how that would be any different than the engine running.
I may just need to order a new pump.
 
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lilthom

lilthom

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any possibility its a directional rotational issue?

I like your thought process but since what I am going to is all components of the Explorer front dress I can't see that as the problem. There is only one way that serpentine belt can go on that pulley. Ha, you are going to make me go look though.
Nope, can't rotate any other way.
 

73azbronco

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I'm not understanding how a sag is producing less than an explorer pump regardless of pulley. Anyway, I tend to think the bleed issue is more in the steering box, taking 20 or so cycles each way engine off, then a few cycles engine on, then 20 or so more each way engine off. Then let it sit overnight and try again. Took me two days, then solid as a rock. BTW, front axle jacked up, wheels off the ground.
 
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lilthom

lilthom

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I'm not understanding how a sag is producing less than an explorer pump regardless of pulley. Anyway, I tend to think the bleed issue is more in the steering box, taking 20 or so cycles each way engine off, then a few cycles engine on, then 20 or so more each way engine off. Then let it sit overnight and try again. Took me two days, then solid as a rock. BTW, front axle jacked up, wheels off the ground.
I am focusing on the large diameter pulley being the issue per Michael Duff's analysis when he had this in their shop doing the hydro boost install. Yes, the Sag should be the better pump. I have thought about just having the pulley swapped out. I don't think the box was ever depleted of fluid during the pump swap. I had a vice grip on the soft lines an it is the lowest point in the system. I will give the cycling one more go.
Thanks,
 
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lilthom

lilthom

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I gave up and took this to a shop to see if they can figure it out. He is questioning whether the Explorer pump can handle 35" tires and the hydroboost system. What is the verdict on this? Maybe the pump is fine but not enough volume for this set up.
 

jimmyk

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Nov 12, 2013
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Did you every figure it figured out? Same issue as you but no hydroboost setup. Everything is brand new and I can't figure it out.
 
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lilthom

lilthom

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Did you every figure it figured out? Same issue as you but no hydroboost setup. Everything is brand new and I can't figure it out.
I switched to the smaller pulley which meant taking the pump out to work on it on the work bench. Once it was all back together with a lot of turning and patience it is working. It’s still a mystery to me just what the issue was.
Sorry I couldn’t give you better direction.
 

jimmyk

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I've heard some people have to go "lock to lock" many, many times, and others have very little problem getting air out of the system.

Thanks for your reply
 
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