Power steering pump overflows

[trevarthan]

My 71 c10 4.1L six 2wd has developed a power steering issue recently.

The guy I bought it from, years ago, said the truck had manual steering from the factory, but he replaced it with power steering components from a similar model (perhaps the V8).

Anyway, power steering fluid is overflowing from the power steering pump cap after the engine is shut off.

I replaced the high pressure supply and low pressure return lines, thinking it was a leak. The return line rubber hose was slightly cracked, so I thought this might be the issue.

Unfortunately, the issue is still happening.

I've been bleeding the system for about 4 hours now, moving the steering wheel lock to lock with the engine off and watching for bubbles.

There must still be a leak because I'm still seeing bubbles after 4 hours and it's continuing to do the same thing if I turn the engine on. Plus the pump sounds terrible with the engine on.

How do I diagnose this? I want to identify the source of the leak without blindly replacing more components. I could replace the pump, but what if it's the gear motor? etc.

Thanks for any help. I'm a little bit at a loss here.

[ElKotze]

Your pitman arm is not centered! Pull the pitman arm off and find the center on your steering wheel by counting turns from lock to lock. Then put the pitman arm back on.

[trevarthan]

Originally Posted by ElKotze

Your pitman arm is not centered! Pull the pitman arm off and find the center on your steering wheel by counting turns from lock to lock. Then put the pitman arm back on.

Why would the pitman arm not being centered allow air into the power steering system?

[AussieinNC]

Replace or overhaul the pump...

the pump casing O ring seals have gone hard and allowing high pressure oil from steering box to flood back into the pump overfilling it....

[ElKotze]

Originally Posted by trevarthan

Why would the pitman arm not being centered allow air into the power steering system?

It's not air in the system, it's pressure build-up because your pump is working against the pressure from the steering arm. It's like you hold your steering wheel against the steering stop constantly. Seen this many times, over flowing after engine shut-off, squealing pump and constant bubbles are typical signs.

[trevarthan]

Originally Posted by AussieinNC

Replace or overhaul the pump...

the pump casing O ring seals have gone hard and allowing high pressure oil from steering box to flood back into the pump overfilling it....

Replaced the pump. Still doing the same thing. I can turn the engine on and move it lock to lock, but after I turn the engine off it always overflows.

[trevarthan]

Originally Posted by ElKotze

It's not air in the system, it's pressure build-up because your pump is working against the pressure from the steering arm. It's like you hold your steering wheel against the steering stop constantly. Seen this many times, over flowing after engine shut-off, squealing pump and constant bubbles are typical signs.

I'm not saying you're wrong, because I admittedly don't know anything about this. Unfortunately, your explanation doesn't make sense to me. It didn't do this before and we haven't modified anything about the pitman arm alignment.

It seems more likely to me that the gear motor has blown a seal and is drawing air into the system.

[trevarthan]

These flare nut fittings, does anyone have the torque specs? I'm not super sure how tight to make them. Just tighten them until they don't leak?

[rsgt]

Originally Posted by trevarthan

Replaced the pump. Still doing the same thing. I can turn the engine on and move it lock to lock, but after I turn the engine off it always overflows.

After you replaced the pump, is it still making noise?

[kwmech]

Originally Posted by ElKotze

Your pitman arm is not centered! Pull the pitman arm off and find the center on your steering wheel by counting turns from lock to lock. Then put the pitman arm back on.

Not even close. The pitman arm will only go on one way (theoretically) with the master spline every 90 degrees

[trevarthan]

Originally Posted by rsgt

After you replaced the pump, is it still making noise?

It only makes noise when there is air in the system, as you would expect.

Moving the steering wheel lock to lock seems to generate bubbles, especially on the left movement.

I’ve replaced the pump, supply, and return lines. The only thing left is the gear, unless I just screwed up the fittings somehow, but they’re pretty straight forward.

My plan is to buy and install a remanufactured gear next.
Posted via Mobile Device

[rsgt]

I had similar problems. I replaced my pump twice. Mine would overfill during the lock to lock bleading. I replaced my gear with this one, which did not require a core. Works good now. https://www.walmart.com/ip/Cardone-2...Gear/156131091

[ElKotze]

Originally Posted by trevarthan

I'm not saying you're wrong, because I admittedly don't know anything about this. Unfortunately, your explanation doesn't make sense to me. It didn't do this before and we haven't modified anything about the pitman arm alignment.

It seems more likely to me that the gear motor has blown a seal and is drawing air into the system.

You wrote in your original post that the PO replaced the manual steering gear with an hydraulic one. I bet he didn't center the new one when he installed it, happens all the time, resulting in exactly what you are experiencing. Now you want to replace the gear and they are not cheap, but to do that you have to pull the pitman arm off the output shaft anyway, so after you did that count your turns of the steering wheel from lock to lock and then try to find the center, like 5 turns lock to lock would be 2.5 turns from one lock to center, then put your pitman arm back on and your problems will be gone, doesn't cost you a dime and takes like 10 minutes.

[ElKotze]

Originally Posted by kwmech

Not even close. The pitman arm will only go on one way (theoretically) with the master spline every 90 degrees

There is more than one way to put a pitman arm on.

[ElKotze]

Originally Posted by kwmech

Not even close. The pitman arm will only go on one way (theoretically) with the master spline every 90 degrees

I know what you mean, actually there's four ways to put the pitman arm on. You need to find the one that centers your steering.

[trevarthan]

Originally Posted by ElKotze

You wrote in your original post that the PO replaced the manual steering gear with an hydraulic one. I bet he didn't center the new one when he installed it, happens all the time, resulting in exactly what you are experiencing. Now you want to replace the gear and they are not cheap, but to do that you have to pull the pitman arm off the output shaft anyway, so after you did that count your turns of the steering wheel from lock to lock and then try to find the center, like 5 turns lock to lock would be 2.5 turns from one lock to center, then put your pitman arm back on and your problems will be gone, doesn't cost you a dime and takes like 10 minutes.

Posted via Mobile Device

[randy500]

This is a huge problem with 2nd gen gen dogde diesels.....here is what is happening.
Your worn out steering box is pushing fluid back into the pump after you turn the engine off.
What? How could that happen, the truck is off.
There are static forces acting on the steering gear when off, such as angle of wheels and angle of vehicle exerting pressure on the front tires, the static forces slowly move the steering box which discplaces the internal fluid to the pump overflowing it.
You can test this by putting the vehicle on stands with the front wheels off the ground... run the engine, move the wheels then turn off, if there is no force on the wheels the steering pump will not overflow.

[trevarthan]

Originally Posted by randy500

This is a huge problem with 2nd gen gen dogde diesels.....here is what is happening.
Your worn out steering box is pushing fluid back into the pump after you turn the engine off.
What? How could that happen, the truck is off.
There are static forces acting on the steering gear when off, such as angle of wheels and angle of vehicle exerting pressure on the front tires, the static forces slowly move the steering box which discplaces the internal fluid to the pump overflowing it.
You can test this by putting the vehicle on stands with the front wheels off the ground... run the engine, move the wheels then turn off, if there is no force on the wheels the steering pump will not overflow.

Ok. Most likely replacing the gear will solve the problem?

[randy500]

Originally Posted by trevarthan

Ok. Most likely replacing the gear will solve the problem?

Yes, but I wouldn’t buy a rebuilt one unless your willing to install a few till you get one that is good, they are notorious for problems. I would buy a used one or a new one from CPP.

[trevarthan]

Originally Posted by ElKotze

You wrote in your original post that the PO replaced the manual steering gear with an hydraulic one. I bet he didn't center the new one when he installed it, happens all the time, resulting in exactly what you are experiencing. Now you want to replace the gear and they are not cheap, but to do that you have to pull the pitman arm off the output shaft anyway, so after you did that count your turns of the steering wheel from lock to lock and then try to find the center, like 5 turns lock to lock would be 2.5 turns from one lock to center, then put your pitman arm back on and your problems will be gone, doesn't cost you a dime and takes like 10 minutes.

I went out and counted.

• 1-3/4 turns to the left is the lock.
• 1-3/4 turns to the right is the lock.
• Wheels are centered in the middle.

Pitman arm looks centered in the middle to me:


Again, I'm not an expert, but I don't think this is the problem.

[trevarthan]

Originally Posted by randy500

Yes, but I wouldn’t buy a rebuilt one unless your willing to install a few till you get one that is good, they are notorious for problems. I would buy a used one or a new one from CPP.

They're $800 new, aren't they? That's crazy.

[trevarthan]

I was having trouble getting imgur to work yesterday, but it's working this morning, so here are pics of the fittings on the pump and supply line.

These are also the fittings on the gear for both the supply and return. My aircraft mechanic friend tells me these are flare nut fittings and are highly reliable.

I'm not sure how much I need to tighten them and I don't think I can get a torque wrench on any of these fittings as I'm forced to use open ended wrenches to tighten all of these. The only torque wrenches I've ever seen are socket wrenches.

Tighten until they don't leak? Good enough?

[randy500]

Summit racing $378
https://www.summitracing.com/parts/clp-cp50014

[ElKotze]

Did you have that problem since you got the truck or did it start all of a sudden?
Can you take a picture of your input shaft (rag joint) with the wheels straight?

[trevarthan]

This problem has been resolved. My son and I replaced the gear with a remanufactured part from O'Reilly Auto Parts. Works perfectly, sounds great, and no longer overflows.

Thanks to all who helped us troubleshoot this issue. Really appreciate it.