2020 Hydraulic oil draining into engine???

[JD2020RU]

My '67 gas 2020 hydraulic fluid has started draining into the engine. She was running fine last week: Hydraulic oil and engine oil levels were right on. Yesterday I went to do some mowing and the hydraulic fluid was a little low and the engine oil was about an inch high. I added some hydraulic fluid and drained some engine oil and started mowing on level ground. After a couple hours, the power steering started getting stiff and the 520 loader began chattering. I stopped and checked the fluid levels and found the hydraulic dipstick dry and the engine oil level 3 inches too high on the dipstick. I'm the 2nd owner (7 years now), it has ~2000 original hrs and is a real clean, well maintained classic. It"s got the 1.38 hyd pump, power steering, locking diff, and 8 speed tranny. It was in the local JD shop a month ago and had the steering arm oil seal replaced, and hasn't leaked since. I've looked over the parts manual and can't see a connection as to how the hydraulic oil could get into the engine??? Hope someone can shed some light on this mystery for me! thanks!!! David

 

[tim s]

The early 2020"s had an open center steering with a steering oil pump mounted to the timeing cover of the engine,the shaft seal would fail on them and let oil into the engine. Check and see if this is the way yours is set up and post the serial number, that will help determine if this is the way yours is. I don't remember the serial # break for this.

 

[buickanddeere]

(quoted from post at 15:44:55 08/15/10) The early 2020"s had an open center steering with a steering oil pump mounted to the timeing cover of the engine,the shaft seal would fail on them and let oil into the engine. Check and see if this is the way yours is set up and post the serial number, that will help determine if this is the way yours is. I don't remember the serial # break for this.

POWER STEERING PUMP™BR>(TRACTOR SERIAL NO. 010001-045199)
Cart KEY PART NO. PART NAME QTY TRACTOR SERIAL NO. REMARKS
1 AR39030 COVER 1 (NLA)
2 F3171R O-RING 1
3 R40122 ADAPTER FITTING 1
4 R27212 FITTING 1
5 R26448 O-RING 3
6 R39208 SPRING 1
7 AR39100 VALVE 1 (SUB FOR AR39063)
8 R26375 O-RING 1
9 R39112 FITTING 1
10 T24388 HOSE FITTING 1 (NLA)
Cart KEY PART NO. PART NAME QTY TRACTOR SERIAL NO. REMARKS
11 R39197 HOUSING 1 - 038519 (SUB R39296 AND (2) R39297)
R39296 HOUSING 1 038520 -
12 R39201 GEAR 2 (12 TEETH)
13 AR39058 BASE 1
14 R39202 SNAP RING 2
15 R39200 SHAFT 1
16 26H70 SHAFT KEY 2 1/8" X 1/2"
17 30H20 PLUG 1 1-7/16"
18 T20273 GASKET 1
19 T22347 SCREW 1
Cart KEY PART NO. PART NAME QTY TRACTOR SERIAL NO. REMARKS
20 AR39061 GEAR 1
21 AR53048 PACKING 1 (SUB FOR AR39060)
22 R27218 FITTING PLUG 2
23 R39209 BOLT 1
24 T22156 BOLT 3
25 19H1733 CAP SCREW 2 3/8" X 2-1/2"
26 T22040 BOLT 1
27 R39297 WASHER 2 038520 -
28 AR39029 HYDRAULIC PUMP 1

 

[tim s]

And it looks like 1967 2020's started with ser. #42721...this is most likely where your problem is....

 

[JD2020RU]

SN is 043756T, and there is a power steering pump mounted on the timing cover. Is this the only way hydraulic oil can enter the engine?

Ouch!

I just posted a couple pics of the 2020 in the YT Tractor Gallery, along with the ones from several years ago. Thanks again for the help, I would have never figured this out. I thought the power steering ran directly off the hydraulic pump....
David

 

[tim s]

I could never understand why they did that on the early ones, a new seal in the pump may take care of it..