Oliver 1650 Pump Noise

[ChevyK30]

I recently acquired a 1968 1650 diesel that has been sitting a long time. After some fuel and clutch repairs I have it running. Then I found it had very low hydraulic pressure. Everything worked but poorly. Replaced the vane pump (had obvious wear inside the ring, like chatter marks) with a new gear pump. Now I have great hydraulic performance but also developed a rattle/hollow metallic ring in the pump area, that is LOUD. I have done the following:

- New pump from reputable dealer, new 3pt cylinder seals, new o-rings at all locations in hyd unit, new bearings on pump drive gear and idler gear, new pump gasket, 2 new gaskets for hyd unit to rear housing, steel elbow for 3pt cylinder relief
- The new pump without the gasket installed had 0.003-0.004" clearance between the mounting flange and hydraulic unit. So I wouldn't think the shaft is bottomed out in the gear.
- I lightly clearanced 2 ribs on the replacement pump with a file that appeared to touch the housing before installing. Definitely not touching now.
- No obvious wear on any of the pump drive gears
- Some wear on PTO drive shaft at flywheel but looks good at pump drive
- Removed hydraulic unit after new pump install to verify pump pickup is not touching reservoir pan (clearanced cup on pan slightly because test clay cut into 2 pieces)
- Replaced hyd filter 2x
- Remote spool valves were lightly stuck so I freed those and cleaned
- Checked flow divider, spool works freely. Small hole in spool land going to the dampening chamber is clear.
- Originally refilled with J20C hydraulic oil, drained and refilled with AW32
- Mowed about 1 hour and hyd filter housing just slightly warm to touch
- Relief pressure before the flow divider is 1900-2000 psi and steady
- Steering max pressure at flow divider 1500-1600 psi at steering lock
- Flow divider spool spring length is 4-11/16". Books says 4-25/32". So it is roughly 3/32" short.

The noise goes away at idle and slowly turning the steering. Like low hyd flow helps. Mowing with PTO loaded doesn't seem to change the rattle. Cranking the tractor without the PTO drive shaft eliminates the noise. Noise does not change with transmission clutch engaged or disengaged. Installing the PTO driveshaft halfway (front splines in hyd drive gear) and rocking shaft by hand seems to replicates the noise.

I shimmed the flow divider spool spring with 3 washers (about 0.120" total). The noise is noticeably better. Especially at 2000 rpm. Steering pressure measured before the flow divider, not turning the steering wheel, seems to have increased slightly. Went from about 200psi to maybe 300psi and gauge does not fluctuate as badly. I am guessing that this 200-300 psi pressure is a combination of the pressure required to open the flow divider and push oil through the rest of the system

Could the flow divider be my problem? Maybe a weak spring causing pressure fluctuations and the pump is loading and unloading causing the rattle? I thought about temporarily removing the flow divider spool spring to see if noise goes away and measure pressure without the divider doing its job.

Anyone have any thoughts or experience with such? I have read the 1650 pump makes noise but this seems a tad too much.

 

[scootergmc]

Your description has me thinking bearing, but you replaced the ones I would consider the main culprits.

 

[ChevyK30]

I would agree. This is the first Oliver I have worked with. The noise is a lot like a relief valve chatter. But I don’t see a problem with the main relief, steering relief, or filter bypass. I haven’t checked the cooler bypass valve. I am running out of ideas.

 

[scootergmc]

I would agree. This is the first Oliver I have worked with. The noise is a lot like a relief valve chatter. But I don’t see a problem with the main relief, steering relief, or filter bypass. I haven’t checked the cooler bypass valve. I am running out of ideas.

Did you replace the bearings in the bulkheads?

 

[tntractor]

It is hard to describe a noise on a forum. But, if the 3 point life is out of adjustment, it makes a disturbing noise. It is the quarter inch threaded rod with a metal cross pin. I made this mistake once upon a time.

 

[ChevyK30]

That is the only bearing I didn’t replace. The videos I watched before I started didn’t mention it and I just didn’t think about it until I was putting it back together. It felt great. But, I may need to revisit it.

 

[ChevyK30]

It is hard to describe a noise on a forum. But, if the 3 point life is out of adjustment, it makes a disturbing noise. It is the quarter inch threaded rod with a metal cross pin. I made this mistake once upon a time.

I agree on noise description. I checked the 3 point adjustment also. About 1-2” free motion at full lift.

 

[Mike(NEOhio)]

Your halfway install of the shaft duplicating the noise leads me to think bearings. Three places. The pump shaft bearing, the idler gear on the bottom of the housing or the drive gear in the transmission. My 1550's idler had worn the snap ring to a knife edge

 

[Mike(NEOhio)]

Forgot the picture.

 

[ChevyK30]

Your halfway install of the shaft duplicating the noise leads me to think bearings. Three places. The pump shaft bearing, the idler gear on the bottom of the housing or the drive gear in the transmission. My 1550's idler had worn the snap ring to a knife edge

Mine also had the worn snap ring. I replaced it. I replaced the 2 bearings on the drive gear in the hydraulic housing. Also the bearing in the idler gear where the snap ring is. Looks like I probably need to revisit the bearing in the transmission housing.

 

[scootergmc]

Just thinking out loud, but if you're going in again, can you run the tractor without the hydraulic unit, with the PTO long shaft installed then uninstalled? I suppose you'd have to put some plywood over it or redirect an oil passage? Is this possible?

 

[Mike(NEOhio)]

Mine also had the worn snap ring. I replaced it. I replaced the 2 bearings on the drive gear in the hydraulic housing. Also the bearing in the idler gear where the snap ring is. Looks like I probably need to revisit the bearing in the transmission housing.

I did a little alteration. Tapped three small holes in the end then ground and filed a shoulder and pilot for a thick hardened washer.

 

[ChevyK30]

Just thinking out loud, but if you're going in again, can you run the tractor without the hydraulic unit, with the PTO long shaft installed then uninstalled? I suppose you'd have to put some plywood over it or redirect an oil passage? Is this possible?

Possibly. I could put the reservoir pan over it and just have to cover the transmission section. If am thinking correctly, I could block the clutch pedal down. The lube pump would not run and the transmission gears would not sling oil. I could also block a rear tire up for an added level of safety.

 

[ChevyK30]

I did a little alteration. Tapped three small holes in the end then ground and filed a shoulder and pilot for a thick hardened washer.

I like that. That should keep it on there. It is interesting that shaft was not too hard to drill and tap. Must just have a case harden and soft in the center

 

[ChevyK30]

I did a little alteration. Tapped three small holes in the end then ground and filed a shoulder and pilot for a thick hardened washer.

I found in an old post you welded the splines on your PTO drive shaft. Were you getting any kind of noise before you did that?

 

[Mike(NEOhio)]

I like that. That should keep it on there. It is interesting that shaft was not too hard to drill and tap. Must just have a case harden and soft in the center

I found in an old post you welded the splines on your PTO drive shaft. Were you getting any kind of noise before you did that?

That was at the back end in the PYO clutch. It was pretty bad. No noise and it actually worked but never sounded right and would not always stop turning. Discs were chewed up and the center plate was warped a bit and blued. Cheapskate that I am I only bought new discs and the tiny springs, fixed everything else.

The shaft isn't really that hard. It had some wear on the diameter but a new needle bearing took care of most of it. I drilled and tapped the holes first and laid out where the shoulder should be then roughed it in on the bench grinder and finished with files. I was going to wire the bolt heads but those socket heads are hard to drill so some Locktite.

 

[ChevyK30]

I tapered a 7/8” wood dowel today. Lightly drove it into the pump drive from the rear. Spinning it by hand it has an obvious clunk at the same place every turn. So I have a gear or bearing that’s not happy. I don’t remember if the 3 gears have the same number of teeth or not. If not it has to be the bearing or gear in the housing. At least I have a place to start

 

[ChevyK30]

That was at the back end in the PYO clutch. It was pretty bad. No noise and it actually worked but never sounded right and would not always stop turning. Discs were chewed up and the center plate was warped a bit and blued. Cheapskate that I am I only bought new discs and the tiny springs, fixed everything else.

The shaft isn't really that hard. It had some wear on the diameter but a new needle bearing took care of most of it. I drilled and tapped the holes first and laid out where the shoulder should be then roughed it in on the bench grinder and finished with files. I was going to wire the bolt heads but those socket heads are hard to drill so some Locktite.

I’m eventually going to have to either fix my splines at the flywheel or buy a new shaft. Right now I’m trying to evaluate the tractor to see what I have and make it functional. Then I plan to making it pretty nice. Very few Oliver tractors around here so I’m trying to save this one.