Newell Gurus

This is a problem I had last year on my coach. I want to record what happened here in case it will help anyone else.

My power steering started getting jerky a couple years ago. It finally got to a point where I had no power assist. And yes, it becomes a beast without power steering.

I can usually fix most things myself. I replaced the hydraulic pump, and spent quite a bit of time talking to mechanics at Newell. After replacing a few more items (including the new hydraulic pump) I finally threw in the towel decided to try to make it to Miami (from Dallas) and let the experts fix it.

It took Newell mechanics 5 man-days (1 guy for 3 days, and another for 2) to finally figure the problem out. (They removed and replaced almost everything two or three times, and even removed the steering gear). 

The problem was in the hydraulic fan motor. Unfortunately it was not documented anywhere that there is something in the fan motor that controls the power steering.  No one thought they were connected... and the fan appeared to be running properly. But in the end the fan was either restricting fluid going to the steering gear, or diverting it.  The fan motor was changed and I was back on the road. 

I was feeling rather dumb that I couldn't figure the problem out. The only redeeming thing I got out of the whole experience was the satisfaction that it took 5 days for professional mechanics to figure out the problem.   

My engine is an S60.

Thank you for posting Alan.

Tom and I were aware that another owner Paul Tracy experienced a similar failure. And it took new hyd pump, new control solenoids, and new steering gear box before it was identified as a faulty fan motor. To the best of my understanding the hydrualic system feeds both the steering gear box and the fan with any pressure regulating device regulating the flow to either . If the fan motor internals allow excess flow through the fan motor, all of the hyd pressure is consumed just pumping fluid through the fan and back to the reservoir.

My comments are hindsight, but for others reading this thread, here is an idea I think would be fairly easy to try if this problem is suspected. Unscrew the hyd return line from the fan motor and cap it. The return to the reservoir would have to be capped also. If the steering problem goes away then voila! the problem is the fan motor. Of course you couldn't run like this for very long, but it's far less effort and money than replacing the hyd pump or steering gear box.

Don't have a loss of power steering entirely but in low speed situations such as jockeying into parking spot it seems to be partially losing power steering. Best way to explain it is kind of like a pulsing sensation when you're turning like it's losing power steering, getting it, loosing it, etc. as you're turning. Assuming this is not a normal thing and wondering if what I'm describing is this issue with the hydraulic fan motor?

Brad,

Consider this as a possible explanation. And, yes, my coach does that too!

In a parking situation the wheels may not be rotating much, if at all, and you are trying to change their direction. There is a lot of weight on those steer tires and a lot of contact area with the pavement. I think the hydraulic pressure you are producing turning the steering wheel causes the high pressure relief valve to open and you get that pulsing sensation. I think it will go away when you are able to rotate the steer tires while turning them. Russ

Both Newells I have owned had the same behavior at close to zero speed.

lets go 3 for 3 with me

tom

Problem solved. All I've driven that was halfway comparable were heavy trucks and there it was not an issue that I can remember, but it's also been many years.

An experience with no power steering caused me to become more familiar with the system.   The hydraulic feed to the steering box (on 567) is a #8 AII braided hose, it must have dropped down at some point and rubbed on the cooling system valve block feeding the aqua-hot and dash heat.  The supply hose to the steering box is fed from the fan control block.  A small hole rubbed into the line caused the fluid to leave the system while trying to back up to a trailer.  A considerable amount of steering input involved when in tight quarters.  When the wheels are not rotating, the 365 ground patch is about one square foot and 9,000 lbs  ground pressure, making it nearly humanly impossible to turn without assist even rolling.  
Those of you having the same supply line configuration might want to inspect for rubbing.  I shudder to think what would have happened at high speeds.