Jinma 254T / Y385T engine - hydraulic pump leaking

pasturesnew · Jan 10, 2006

Hi All - and Happy New Year!

At 85 hours my Jinma 254T has developed its first leak - fluid dripping at idle speed from a joint in the hydraulic pump body. Tried tightening the (4) bolts a little, which seemed to slow it but not stop it. I assume there is a gasket - hopefully the one in the spares kit, listed as part Y380T-02019.

Is there a recommended procedure for dismantling and reassembling the pump body to fit this gasket? Is there a correct torque setting for the 4 bolts? Any advice much appreciated, as always!
thanks

greg_g · Jan 10, 2006

There are some HERE, but I suppose you could make your own as well. As far as torque, I've found 65 ft/lbs sufficient to stop most hydraulic leaks on my KAMA. But keep in mind, how much torque can be applied is relative to bolt size.

//greg//

pasturesnew · Jan 10, 2006

Thanks Greg,

I am now thinking that there is no gasket at the point of leakage - joint looks metal-to-metal - so maybe damaged seal? I don't seem to have an exploded diagram of the hydraulic pump, but the casing seems to consist of two end pieces, attached in front of and behind the centre body to which the elbow connector is attached. The leak is from the front joint.
There is no FEL fitted but the rear TPL has been used for a lot of harrowing with a fairly heavy piece of kit. Could that be enough to damage a seal?

greg_g · Jan 10, 2006

( Could that be enough to damage a seal? )
Assuming the pump was assembled properly in the first place, lifting typical implements should not cause such a leak. I believe your TPH is rated to lift ~875 pounds.

I haven't broken apart one of those pumps personally, but my first guess would be THIS ONE. On the other hand, it might be nothing more than a large cirumference O-ring.

//greg//

Soundguy · Jan 10, 2006

Like greg said... find out what fastener size you have.. then look up the max torque spec for that size bolt. pay attention to grade of bolt, and material being threaded into.

IE.. cast aluminum is going to be weakest.. next is cast iron.. then is steel.. etc.

Soundguy

pasturesnew · Jan 10, 2006

Correct Greg - that is the gasket supplied in the spares kit. But I think when I take it apart there will be O-rings - the fit between the parts seems too close for a gasket.
Three of the four connecting bolts seemed pretty loose - much less than your 65. They are M10 x100 bolts, so maybe I'll torque them up a little more before resorting to dismantling.
If I do have to take it apart, can I assume lowering the TPL and leaving it in float will be sufficient to take the pressure out of the system? Should I fill the pump cavity on reassembly or is it self-priming?

pasturesnew · Jan 10, 2006

Hi Soundguy,
Fixings are M10x100, casing looks cast ferrous - Greg's 65ft/lb sounds ok to me - what d'yer think?

Affordable · Jan 10, 2006

There is no Gasket inside the pump only O-rings, if the case was a little loose from original assembly it would cause the o-ring to blow out . You are going to need to purchase a rebuild kit for the pump which includes all the o-rings and a new seal.We have the kits as well as other dealers I'm sure.The 65 lbs of torque sounds right, just make sure you tighten them evenly when you re-assemble.
Tommy
Affordable Tractor Sales Co.

pasturesnew · Jan 10, 2006

Thanks Tommy,
Will check the spares kit supplied with tractor for anything that looks like the necessary bits (there are a lot of seals, etc in there!). Dismantling will have to wait a week or two, so hope to get parts from UK by then if necessary.

JINMA224XR · Jan 13, 2006

At 85 hours my Jinma 254T has developed its first leak - fluid dripping at idle speed from a joint in the hydraulic pump body. Tried tightening the (4) bolts a little, which seemed to slow it but not stop it. 

Hey Ashley,

Happy New Year, How's it going over in France?

Sorry to hear about your hydraulic pump leakage, but you know, these tractors will eventually spring a leakage somewhere.

I looked at my hydraulic pump more closely when I got home today, and Mine also has some seepage on the front. It is a large piece in front that has a gasket, with several 13mm bolts, and yes several needed tightening. I'll try to get to it tomorrow, as I will have to remove the fan belt to get to all of the bolts.

By the way, I did my headbolt retorqueing and valve lash adjustments. You can go over to NYCTO Forum to read the long thread in the Y380T engine section. I think that you may find it interesting, especially since it appears that the valve lash setting in the book has been revised, but not updated in the engine manual specifications.

Here's the Site: http://nortrac.proboards26.com/index.cgi

Hope you have good luck on the hydraulic pump leakage. Try to be extra careful on the torqueing of the hydraulic bolts, as it may be aluminum involved. Not sure, as mine is painted black, and I didn't look close enough to see whether any of it was aluminum(Soft Threads), you know.

Have a nice day,
Joe /forums/images/graemlins/cool.gif