Hydraulic steering issue 5610S

[F3506]

This is a 2wd model. Son in law and one other young man have been driving this tractor for the last couple of years so I'm out of touch how things progressed, but steering wheel became very difficult to turn, but steering still functioned. Jacked up front end and steering was still just as difficult. Disconnect hydraulic cylinder from steering and wheels turn left and right by hand easily, so the front end is ruled out.

No auxiliary steering pump, only the transmission mounted hydraulic pump where the filter spins on. Looked at the parts that I supposedly have online and notice I do not have a check valve on the steering cylinder (cylinder was rebuilt a year or so ago). Also found hydraulic oil cooler caked up with junk so that was cleaned out. Hydraulic filter was changed as it was time for that anyway.

I don't have a gauge and proper fittings handy to test pressure on the steering lines, but decided to disconnect one line and just watch flow. Disconnected where the check valve may or may not supposed to be. Steering wheel became easier to turn with engine running, but the wheels didn't move much due to the open line. Took the 90ｰ fitting out of the cylinder just to make sure there was no check valve there. Nope. Started it up one more time and now suddenly had good flow out of the steering line even with no turning on the wheel. Only came out in spurts before when the wheel was turned. Buttoned it back up and the steering seems to be fixed?

So what happened? Was there an obstruction in the line that I didn't see come out? Is it a fluke and steering will fall apart again soon? Do I really need the check valve?

Any input would be appreciated. I'll visit with the dealer tomorrow, but advice there seems to be hit or miss.

[showcattle]

It doesn't have the power steering pump on the left hand side of the engine up front?

[showcattle]

The pump is left of the oil filter, right and below the alternator.

[F3506]

No, it doesn't have the pump. The front cover has the bracket for the pump mount, but there's just a block off plate installed. Tractor has one belt. Crank, water pump, alternator.



And I looked through my file. Back in 2000 I got a recall letter from New Holland saying the steering might suddenly pull to the left so they would install this check valve for free on the large side of the cylinder to prevent that. I guess it got lost during the rebuild.

[F3506]

Hard steering is back again. Steering still works, but it feels like power steering from a 70's car after the motor stalled and you're driving under 10 mph.

Anyone know what it takes to rebuild that particular hydraulic pump?

[RickB]

Maybe you need a better understanding of the steering system. If the usual dedicated gear driven power steering pump isn’t present at the left front of the engine, it may have a flow divider downstream from the main pump. The 10S series have substantial differences from the earlier U.S. and British built Fords.

[F3506]

I won't argue that I need a better understanding of the steering, but visually looking at it, it's fairly straight forward. There are two hydraulic pumps mounted on the transmission. One on top that feeds the rear remotes and 3 point linkage, and the one on the side that has the filter that feeds the steering. Lines flow from the side pump to the steering gear box, and then on to the cylinder mounted on the front axle.

The top mounted pump can be changed out for one with a manual diverter valve to run a front end loader, or a front end loader can just be plugged into the rear remotes as it all runs off the top pump. That pump seems fine as the 3 point arms and remotes still work fine.

Only hydraulic issue is steering, but if you have any specific ideas, I'm all ears.

And yes, this is a S series built in Mexico, bought new in 99. Not like the older Ford that I traded in for it.

[RickB]

I’d be doing some pressure testing and leakage testing before I condemned the pump. The system relief valve and steering cylinder piston seals have to be ruled out as causes.

[F3506]

I'm with you. I don't have a 2,000 psi gauge, and I've read pressures can reach 1750, so I need to get a new gauge before I can do any pressure testing.

What had me jumping to pump was little no no flow out of the line to the steering cylinder when disconnected at first, but after repeated testing and the flow picked up to what seemed normal, steering got easy.

But having just changed the filter could have introduced air into the system and might explain the limited flow at first. I'll do more testing once I get the gauge.

[F3506]

Well pressure tested fine on both sides of the cylinder. I did notice some nasty looking fluid coming out of the cylinder when disconnected, so I did some further questioning and discovered the kid that had been using it (was going to buy it until the divorce nixed those plans) had let the hydraulic oil cooler get completely clogged and got things a bit hot while mowing in the summer (it's taken me some time to get around to this).

Oil looked fine on the dip stick, and looked fine when I had loosened the filter to drain some to get a look at it, but when I drained it, the fluid looked completely trashed. He had discovered the clogged up cooler and cleaned it before he alerted me to the steering just "suddenly getting really stiff right as he pulled up to the barn" Turns out it happened before and he tried to diagnose and fix it himself, and ended up hiding some of the clues.

Fluid and filter change seems to have it back to normal.