High pitch Hydraulic or Gear noise after new pump install...

I replaced my 12GPM pump with a fresh 17GPM pump on my Farmall 504 recently. I bought both pump cover gaskets (.019 and .024) and used the original gear. The gears looked good and I think I used the .019 gasket. I put in new filters and all new orings. I believe the original style filters are only good for the 12GPM pump. I called (Precision Products?) who make a spacer that allows use of a larger, modern filter that can handle the flow, but is backordered.

I have said this to get to the problem. When running there is a high pitched whine that sounds like it is comming from the flow divider.


I had my father listen to it and he thinks it is from the increased turbulent flow though the rubber hydraulic hose (not stock) causing the noise. I think it may be the gear mesh is too tight transmitting the sound up the hose. Or it could be the flow divider some how resonating? Or the pump is starving with the smaller filters...

Is this normal or acceptable with a new pump? The hydraulics are FAST and the steering works much better. It just has a whine now.

I know Hugh, Allan, Rusty and the like can probably help here.

Thanks and I apoligize in advance for the long post,

Charles

FLowing substantially more oil through a system can cause serious destructive cavitation. Sharp bends (as the metal Elbow on the line) can do it, as can a diverter designed for 12, running 17gpm. A higher capacity priority valve, and a more hydrodynamic fitting might do it.
With that said, there are some serious noises made in hydro systems that cause no issue. If the system is heating up abnormally, I would worry enough to fix it. If the whine is obnoxious, I would fix it. If neither, I would probably live with it. JimN

I have an IH parts manual for this tractor and it seems the flow diverter is the same for all hydraulic pumps (up to 17 GPM). I agree the 90 degree boss fitting is an abrupt change in direction and I plan to change it to a sweeping 90. As for heat, I have not noticed any significant change in oil temp.

I think first I will change the fitting. Second, get the high flow filter. Third, if required use the .024" gasket to give the gears an extra .005"

As I think about it, I used two gallons of Lucas Hydraulic Booster added to the hydraulic oil after I change the pump to increase oil performance and to control minor leaks. My oil leak is virtually gone at the quadrant.

Thanks JimN,

Charles

If I remember correctaly that flow divider is adjustable. You see the turn valve on the left side between the two big lines. I used to have a 504 and the pump was getting wore. I adjusted that valve so it dumped less oil and improved speed of functions somewhat until I got around to replaceing the pump.

Dunno,

I'm inclined to go along with Scott's line of thinking; you're overpowering that valve. Does it get hot?

I'd try to open 'er up a little and see if the steering will take a bit more of the oil.

Really, really doubt if the problem is the 90-degree fitting.

If it were gear whine, one would think you'd hear it at the pump; not this far downstream.

Good luck,

Allan

Allan, it doesn't seem to have a hot spot at the flow divider, but I have not dogged the fire out of the hydraulics either. It has a power steering air-over cooler that is plumbed into the hydraulic circuit.

It sounds like a gear whine but the sound is more aggressive when I activate a remote and steer. The sound is not unbearable but different, I wish I could record it and post it here.

I just got home from work and I am going to play with the flow divider adjustment plunger. Also I think I may get a piece of hose to trace the sound and use my non-contact temp gun to take some readings.

Thanks all, I'll get back with my findings.

PS, I am in need of a 368 971 R1 clutch/brake return spring for a Farmall 504. EBAY is fresh out.

Charles

Charles, I have some very limited experience in dealing with those steering issues.

I think the high pitched whine when nothing is being operated is usually associated with the high pressure flowing past a popoff/check valve somewhere at the rated psi of the check valve.

There is also a different whine associated with the operation of the hydraulics (such as a loader) which could be a cavitation (a pulsating noise) or groan from lack of fluid such as a plugged filter, low fluid level, or cold weather/fluid that is too cold to flow, a suction leak, leaking seal in the pump area, etc.

I'd first suspect that someone adjusted the flow divider to push more fluid to the power steering with the old worn out 12 gpm pump. Now you are getting too much which fluid opening the bypass on the power steering.

If your attempt to adjust the middle screw on the flow divider doesn't fix it, then you could have something plugging up the system from the power steering forward or a bad check ball/valve. Look under the seat for the check valve that is there. There may be another where the power steering line goes to the oil cooler if you have that on yours.

I think that flow divider adjustment screw may shut if off completely to the power steering which would help evaluate it.

We'll wait to see what you find out.

I have news. I found the plunger was ALL THE WAY OUT! I screwed the plunger all the way to the seat on the flow divider. All noise ceased! Hydraulics worked as normal. Opened it 1 1/2 - 2 turns off seat until I could steer with minimal noise (still cold oil, 90-95 degrees). Fast idled for 10 minutes then bush-hogged for about 20 minutes, flow divider casting temp was at 124 degrees and fairly quiet.

I have a JIC to ORB fitting and a swept 90 MJIC to FJIC I may install to help the flow into the flow divider. Maybe this will smooth the turbulent oil flow and further quiet the divider.

Thanks, here is a picture of the current arrangement. Tomorrow I will post the 90.

Cool and quiet like an air conditioner!!! JimN

Its more like an old window unit! I am not going to do the 90 degree fitting now. When I closed the flow divider screw all the way in the noise and the steering stopped. So I now know the noise is in the divider. I am going to accept the noise until I tear into the flow divider and see how it looks. The Blue Ribbon says the "cartridge" it replaceable. If I need to this, I'll bite the bullet and call the local Case/New Holland dealer.

Within the next few weeks, I hope to plumb in the 3-spool loader valve and see how it all sounds. I am going to use the pump output to feed the "IN" on the valve and then use the "OUT" to feed the flow divider. Return will go to the fill plug at the IPTO housing. I know Allan NE suggested the PTO pump, but I have passed the point of no return and I have all the fittings and hose.

My proposed new hydrualic layout...


I have spent a small fortune on this tractor. It should be almost equal to a good, newer one by now!

Charles