Anonymous-0

Well-known Member
My friend just purchased a '76 JD 4630(w/duals). 10,000 total hours with 3,000 hours since the last engine overhaul(allegedly). The tractor came with an almost brand new front end loader "Ez On" sp?? and grapple fork.

Anyway, he's noticed a few issues but unfortunately has doesn't have access to the 'net yet so I will ask for info. on his behalf:

1/ Hyd. chattering when operating front end loader, loader is connected/plumbed into the rear SCVs - is the 4630 hyd. system similar to the 4020('72)?? if so I have a fair understanding of that system.......I forgot to ask if this was happening with the clutch pedal depressed or not..........

2/ Brakes seem to grab when applied, he says he finds it difficult to feather them?

3/ Starting system - batteries are finished/wont take a charge - are the 2 6V batteries connected in series a sufficient combination or would 2 12V batteries in parallel be a worthwhile upgrade?

4/ Transmission - difficult to get out of park(even though it's parked on level ground) Any linkage adjustments/wear?? Lubrication required??

Are there any issues/problems these particular tractors are prone to? He plans to change all of the fluids, filters, clean the trans. pump screen, etc. so he can start with a clean slate but would like to know if there are some other things he should keep and eye out for??

Thanks in advance,

Glen
 
1/ Hyd. chattering when operating front end loader, loader is connected/plumbed into the rear SCVs - is the 4630 hyd. system similar to the 4020('72)?? if so I have a fair understanding of that system.......I forgot to ask if this was happening with the clutch pedal depressed or not..........

Clutch pedal position has NO effect on hydraulics on this tractor, as transmission pump is ALWAYS operating on this machine, even with clutch depressed.

2/ Brakes seem to grab when applied, he says he finds it difficult to feather them?

???

3/ Starting system - batteries are finished/wont take a charge - are the 2 6V batteries connected in series a sufficient combination or would 2 12V batteries in parallel be a worthwhile upgrade?

Factory setup works just fine. 12-Volt batterys NOT an upgrade unless BIG CA.

4/ Transmission - difficult to get out of park(even though it's parked on level ground) Any linkage adjustments/wear?? Lubrication required??

Lube the linkage with spray lube. IIRC, there may even be a zerk or two.
 
Thanks for the reply,

1/ I guess he may as well get the hyd./trans. oil and filter changed as well as clean and inspect the trans. pump screen.(I'm assuming that is the same as a 4020?)Then he can confirm hyd. pressure and go from there......

2/ Is there anything in the brake valve/s that would cause them to apply the brakes rapidly rather than being able to feather them?

3/ What kind of CCA is big? 1000 plus??

4/ Will lube and check for zerks..

Thanks again,

Glen
 
I would just keep it origginal, with the two 6-Volt batterys in series. That system worked well.
 
(quoted from post at 00:13:16 06/07/08) My friend just purchased a '76 JD 4630(w/duals). 10,000 total hours with 3,000 hours since the last engine overhaul(allegedly). The tractor came with an almost brand new front end loader "Ez On" sp?? and grapple fork.

Anyway, he's noticed a few issues but unfortunately has doesn't have access to the 'net yet so I will ask for info. on his behalf:

1/ Hyd. chattering when operating front end loader, loader is connected/plumbed into the rear SCVs - is the 4630 hyd. system similar to the 4020('72)?? if so I have a fair understanding of that system.......I forgot to ask if this was happening with the clutch pedal depressed or not..........

2/ Brakes seem to grab when applied, he says he finds it difficult to feather them?

3/ Starting system - batteries are finished/wont take a charge - are the 2 6V batteries connected in series a sufficient combination or would 2 12V batteries in parallel be a worthwhile upgrade?

4/ Transmission - difficult to get out of park(even though it's parked on level ground) Any linkage adjustments/wear?? Lubrication required??

Are there any issues/problems these particular tractors are prone to? He plans to change all of the fluids, filters, clean the trans. pump screen, etc. so he can start with a clean slate but would like to know if there are some other things he should keep and eye out for??

Thanks in advance,

Glen

Sounds to me like the brake pads are coming apart. It's pretty common on those old row-crop tractors. The pads will come apart, and the material will plug the suction screen. An easy way to check is to drain the hydraulic oil and pull the suction screen. If the screen is clogger with thick, fiberous material AND brass flakes/slivers, then you're looking at brake material (if the material looks more like paper, without the brass slivers/flakes, then you'll looking at clutch material). If the screen is plugged, it'll likely be causing the chatter problem.

Those brakes are a big job. Both final drives have to come off. New pads have to be riveted to the plates... and if there's been metal-to-metal contact, then some parts will need to be replaced.

As far as the batteries go, I gotta disagree with some here. These were old machines by the time I started working on them, so my experience is kinda skewed... but I think these are some danm hard-starting tractors even when things are working right. If it was mine, I'd upgrade to a couple of 1000 CCA truck batteries with 3/8" studs (group 31? don't remember for sure), and hook them up in parallel with new cables. Those truck batteries are hard to beat for the price.

And as I recall, those tractors are 1000RPM only. I think your only options for running 540 equipment would be either to put on an adapter and run the engine slow (in which case you might not have enough power for what you're doing), or find a $$gearbox$$.
 
I forgot to ask, can this tractor be modified to operate in 540 rpm PTO mode as well as 1000rpm??
If so what's involved??

Thanks,

Glen
 
Thanks for the reply,

He'll be pulling the screen when he changes the oil & filter, then he'll have an idea where he stands with the brakes, didn't sound like it was down the metal yet though like some tractors out there.....

We use those batteries you mentioned in our truck fleet, 950 or 1000 CCA I think? Right around $90.00 a peice I'm told....

I was talking to my friend today and I guess the baler he has can be changed from 540 rpm to run with 1000 rpm PTO input by flipping the right angle drive over or something?? Case IH baler, not sure on model # though, I'm not familiar at all??

The haybine he has is 540 PTO rpm as well but he should be able to get away with running the engine slower and gearing up I would think, probably get better economy in the process.


Thanks again,

Glen
 
No, the 4630 never had a 540 option. The only way to get 540 is with a 44?0 tractor or smaller The only way to power a 540 implement is with an adapter on your 1000 shaft with the engine not far off idle. USE EXTREEM CAUTION if you do use the adapter. Get yourself a hank held tachometer to figure out at exactly what engine speed produces 540 RPM. 540 implements will break when the input speed is doubled!!
 
Thanks for the reply,

The PTO is only going to affect his haybine, the baler can be converted to run with 1000 rpm input, but we'll confirm that speed as you say and stick to it.........

Glen
 
Even with the 100% duty cycle trans hydrualic charge pump. It pumps less oil than what a loader uses.
The trans pump also has to supply pto and tranmission oil. As the clutches,seals and pump wear.
The front high pressure pump can run out of oil when two or four cylinders are used along with the power steering.
The return line form the loader must always be plumbed into a ported trans oil filter cover.
It"s not going to make things worse either if the loader supply line is taken from a power beyond circuit.
 
Thanks for the reply,

I'm trying to get a handle on this system(4630)........does it operate the same as a 72' 4020 where the trans. pump supplies oil to the main pump housing and any unused oil goes through the cooler back into the trans. sump?

The loader is hooked into the SCVs so the return oil should be going back into surge pressure relief valve so it can re-enter the loop where it belongs, correct?


Also, you say the trans. pump on the 4630 supplies oil to operate functions in the transmission and PTO?? And that's before it gets to the main pump, right??

So, there'd have to be a loss in the charge oil before it gets to the main pump or a loss in the high pressure system that is dumping back into the sump in order to cause the high press. functions to suffer(like the SCVs, rockshaft, etc)???

One last question, pertaining to our '72 4020, where does the oil come from for the valve that operates the PTO slave pistons?


Thanks again,

The advice is greatly appreciated,

Glen
 
(4630)........does it operate the same as a 72" 4020 where the trans. pump supplies oil to the main pump housing and any unused oil goes through the cooler back into the trans. sump?
Yes

The loader is hooked into the SCVs so the return oil should be going back into surge pressure relief valve so it can re-enter the loop where it belongs, correct?
The oil should be entering the trans oil filter between the filter inlet and the trans pump discharge.


Also, you say the trans. pump on the 4630 supplies oil to operate functions in the transmission and PTO?? And that"s before it gets to the main pump, right??
Yes

So, there"d have to be a loss in the charge oil before it gets to the main pump or a loss in the high pressure system that is dumping back into the sump in order to cause the high press. functions to suffer(like the SCVs, rockshaft, etc)???
More so leaks on the low pressure side which starves the high pressure pump inlet side. Or higher gph leaks on the high pressure side than low pressure pump can flow.
The 4630 has a factory update kit for the high volume trans pump to compensate for age/wear related leaks.
(INCREASED CAPACITY)
(QUAD-RANGE)
TRANSMISSION OIL PUMP - CONTINUED
(INCREASED CAPACITY)
(QUAD-RANGE)
Cart KEY PART NO. PART NAME QTY TRACTOR SERIAL NO. REMARKS
1 R41041 CAP SCREW 1
2 24H1305 WASHER 1 13/32" X 13/16" X 0.065"
3 R66061 HALF CLAMP 1
4 24H1653 WASHER 1 13/32" X 1-1/4" X 0.120"
5 R48792 WASHER 1
6 R61477 OIL TUBE 1
7 R56462 O-RING 2
8 R42849 BALL 1
9 R227R SPRING 1
10 R26448 O-RING 1
Cart KEY PART NO. PART NAME QTY TRACTOR SERIAL NO. REMARKS
11 R63469 FITTING 1
12 AR78366 OIL LINE 1
13 R30959 LOCK PLATE 1
14 19H2021 CAP SCREW 1 3/8" X 5/8"
15 R41006 CAP SCREW 2
16 ........ GEAR 1 (SUB AR93313)
17 ........ DOWEL PIN 1 (SUB AR93313)
18 AR85538 HOUSING 1 (MARKED R63709 OR R82163) (SUB AR93313)
19 R61475 MANIFOLD 1
20 R47144 O-RING 1
Cart KEY PART NO. PART NAME QTY TRACTOR SERIAL NO. REMARKS
21 R71048 OIL TUBE 1
22 A3917R O-RING 1
23 AR40669 OIL LINE 1
24 R43256 CAP SCREW 1
25 R41007 CAP SCREW 1
26 R51383 SELF-LOCKING SCREW 2
27 R43252 CAP SCREW 1
28 15H558 PIPE PLUG 3 1/8"
29 AR93313 KIT 1
.. AR75648 OIL PUMP 1 INCREASED CAPACITY, COMPLETE PUMP


One last question, pertaining to our "72 4020, where does the oil come from for the valve that operates the PTO slave pistons?
Trans oil pump.
 
Glen,
The rockshaft housing and pump drive shaft must be removed to R&R trans pump. One should remove trans pump drive shaft to inspect for wear as they have been known to get rounded edges.
 
Honestly don"t know, never swapped one out.
It has to be less work to install the high volume pump and a ported oil filter return cover. Than it is to replace every seal in the transmission.
 
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