Back pressure

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leeboy50cub
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Back pressure

Postby leeboy50cub » Tue Oct 17, 2017 6:30 pm

1950 cub. Can hydraulic fluid leak from system into crankcase to create back pressure??? I'm losing hyd fluid with no puddle or drips that I can see ,got a lot of back pressure in crankcase . any thoughts on this? Smokes a lot too. Thanks

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tmays
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Re: Back pressure

Postby tmays » Tue Oct 17, 2017 6:40 pm

Sounds like you have two separate issues. Hydraulic pump seal gone, allowing hydraulic fluid into crankcase. Pressure in crankcase sounds like piston blowby.
Thomas

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Re: Back pressure

Postby Bob McCarty » Tue Oct 17, 2017 6:59 pm

The seal Thomas mentioned is an o-ring that goes on the drive shaft of the pump. You'll have to drain the block, remove the manifold lines, remove the pump and open it up to access the o-ring. If the hydraulics were working fine you probably don't need to rebuild the pump. TM Tractor (forum sponsor at the bottom of the page) sells both the separate o-ring and pump rebuild kits.
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leeboy50cub
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Re: Back pressure

Postby leeboy50cub » Tue Oct 17, 2017 7:20 pm

Thanks Bob and Thomas . can you tell me where to find manual to do this project?

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ricky racer
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Re: Back pressure

Postby ricky racer » Tue Oct 17, 2017 7:44 pm

Manuals at the top of this page. Free to download.
1929 Farmall Regular
1935 John Deere B
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1952 John Deere B
1953 Farmall Cub

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Re: Back pressure

Postby Bob McCarty » Tue Oct 17, 2017 7:52 pm

Click on "quick links" upper left, then on "PDF manuals", then "service manuals", then "Blue Ribbon service manuals", then "GSS 1411". Can't do a direct link to get there.
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Re: Back pressure

Postby Bill Hudson » Tue Oct 17, 2017 8:07 pm

tmays wrote:Sounds like you have two separate issues. Hydraulic pump seal gone, allowing hydraulic fluid into crankcase. Pressure in crankcase sounds like piston blowby.


You betcha.

Bill
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John *.?-!.* cub owner
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Re: Back pressure

Postby John *.?-!.* cub owner » Tue Oct 17, 2017 8:13 pm

May not be bad rings in engine causing blow by, may be crankcase over full with Hytran. A cousin called me about his cub, said it was leaking fuel into the crankcase, and engine was losing power. When he said he had been adding fluid to the touch control I explained to him about the pump. He repaired the pump and changed engine oil and had a much better running tractor
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Re: Back pressure

Postby ntrenn » Tue Oct 17, 2017 9:03 pm

Ditto on the hytran leak. Its NOT engine oil and turns your good cub into a smoker. If you buy the ih pump seal kit it has instructions and all the gaskets to go with all the seals and orings. No key but your local hardware store will have the key for less than a buck. Dont forget to stake the lock retainer...lest you have to pull it back apart to stake :D

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Re: Back pressure

Postby ShawnAgne » Wed Oct 18, 2017 6:40 am

Also make sure you put the gear back on the proper way. Don't ask me how I know.....
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inairam
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Re: Back pressure

Postby inairam » Wed Oct 18, 2017 8:03 am

This is long old post that I found helpful on the pump viewtopic.php?f=1&t=40331&hilit=hydraulic+pump+seal

I do agree with the previous posters that the hydraulic fluid/ oil burns more than oil. My 49 was doing the same thing. First fix the seal on the hydraulic pump, change the oil and then see what your back pressure/oil burn looks like.

Do not lose the tab washer locking the nut that is holding the gear. you need that. May even want to use that and a lock nut to hold the gear in place. It is no fun fishing that gear out of the oil pan.
When you only have 9 horsepower you need to know the names of all of the ponies!

leeboy50cub
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Re: Back pressure

Postby leeboy50cub » Wed Oct 18, 2017 7:59 pm

Thanks for all the info! But still a ??. Are their two different pumps? I'm finding pics of the resivoir one with lots of parts and a smaller one with a few parts and o rings.

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tmays
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Re: Back pressure

Postby tmays » Wed Oct 18, 2017 8:11 pm

Only one pump. The large one under fuel tank is hydraulic body. The pump is attached to front left side of engine. The pump is the culprit.
Thomas

inairam
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Re: Back pressure

Postby inairam » Wed Oct 18, 2017 8:43 pm

There is only one pump on the Cub but there are several changes over time so there are a few different internals of the pump and seal.
When you only have 9 horsepower you need to know the names of all of the ponies!

leeboy50cub
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Zip Code: 15717

Re: Back pressure

Postby leeboy50cub » Thu Oct 19, 2017 4:29 am

OK, thank you. Think I got it now. Going to order kit from TM. Keep ya posted, thanks again to all.


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