Hydraulic tank question 450c

[fullsizejohn]

1979 450C track loader. Hydraulic system seems to work great...but it pushes oil out of the top of the tank. Enough that it runs down on the track. I assume the tank is pressurized? Maybe I need a new tank cap? When I get off the machine and it's hot, removing the cap verifys there is some pressure there. Thanks!

[Mikeforester]

Hi,

Sounds like the system is over filled with oil . The oil should be mid way up on the sight glass. There needs to be a few inches of headspace for the oil from the top of the tank to account for the extra volume of oil when cycling the cylinders (especially with a loader). Unless the oil is contaminated with water, in which case I would suspect the cap and it's mount as water can sneak in that way.

Mike

[B Town]

Does your tank have a spin-on filter or is yours old enough to have the filter in the tank? Has it been changed recently?

[fullsizejohn]

It does have the spin on filter. The filter is behind the front grill on mine.

[Jim B]

The spin on filter behind the grille is the transmission filter ( uses the same filter as the engine oil filter). If you don't have a spin on hydraulic filter (it is larger than the one behind the grill) under the right arm rest next to the hydraulic tank fill point, the hydraulic filter is in the tank. According to the parts catalog the change to the spin-on external of the tank was at 450C serial number 354286. 354285 and prior used the in tank filter. Sounds like you have the in tank return filter and there is a possibility it is plugged. It would be under the cover, bolted on the tank, the fill cap is on. This will sound like a broken record but have you ordered at least an operator's manual? It would help you with these maintenance items.

[fullsizejohn]

Yes I did get a service manual it just wasn't with me today. My machine is on the farm about an hour away. Mine is a serial number beginning in 326. I will take a look. Thanks

[gregjo1948]

Jim B--- Are you sure about the hydraulic and engine filter being the same. Any hydraulic filter I've purchased is far more expensive and I thought it was because they are a better filter.

[Jim B]

If your serial number is 326xxx, it is prior to the parts catalog serial number change to the spin-on filter. Your filter should be inside the hydraulic reservoir.

I would recommend getting an Operator's Manual to go with your service manual when you can, it may be more help to you at this time. JD shows publication # OMT71337 as the Operator's Manual for a 450C. The Operator's manual has more info on normal maintenance, like changing filters and oil, lubrication and adjustments. They often don't put those same "normal" maintenance details in the service manual as the writers would use the theory that the dealer mechanics are familiar with changing filters, etc. from previous models and/or the dealer's shop has copies of the operator's manuals in their libraries, if needed. I have a couple JD Operator's Manuals that are printed with "Dealer Service Shop Copy" on the front cover.

[Jim B]

Good morning gregjo1948,

Sorry if my wording was confusing. I posted that the filter behind his grille was the transmission filter. I said the engine and transmission use the same (part number) filter, I didn't say the hydraulic and engine filters were the same. I described where the spin-on hydraulic filter would be located (under the right armrest) and that the spin-on hydraulic filter was larger than the one behind the grille. I know my 450E uses the same JD spin-on (T19044) for engine, transmission and winch. The hydraulic spin-on is AT113114. It is larger and is located under the right arm rest. I just checked the parts catalog confirmed the 450C is the same, with the exception that prior to 450C serial number 354286 the hydraulic filter (not a spin-on type) is located inside the reservoir. Hope this helps clarify my post.

Jim

[B Town]

There is an often neglected filter in the right box/hydraulic box. It is either under the bolt on cast cap on top of the tank or in very late C series,?it is a spin on filter. You need to change this. Have you observed the pop-up head while raising and lowering the loader??

[fullsizejohn]

pop-up?? Sorry i dont have my manual with me.

[B Town]

There is a 1” hole in top of the right box lid. It is towards the rear of the arm rest lid. In that hole there is a vertical rod. It should have a roll pin or pin on the top. This rod is connected to the bypass valve and spring actuated. When the oil is at operating temperature, and you are raising/lowering the loader, if the rod pops up/moves 1/2” - 3/4” you know there is a restriction. Most of the time it indicates the filter is plugged and at end of cycle.

[gregjo1948]

Jim B--MY BAD, I didn't read your post correctly. Sorry.

[Jim B]

Morning gregjo1948,

That's fine, I have those days too, sometimes worse. Sometimes a wrong or mis-understood post brings out some good information, its always worth asking a question if things don't seem right. Describing things doesn't always read the same to others as we interpret our written words.

Hope you have a good day,

Jim

[fullsizejohn]

Ok, I have my service manual and operator's manual. I see the filter in the tank diagram. Easy enough..... but I can't find the part number for that hyd filter. The napa site tries to point me to the spin on visible filter. Anyone have that filter part number?? I looked in the FAQ section, it was too small to read even with a magnifying glass.
1979 450c track loader