Jinma 284, Y385T engine, zero oil pressure, bad pump?

[quicksandfarmer]

Disconnect the oil pump outlet pipe from the engine block, it's held by two 13mm bolts. The oil pump is held by a single 13mm bolt. Once the pipe and the bolt are off it just slides down. Remove the two 13mm bolts that hold the outlet pipe to the pump.

Ordering a new pump: there are three versions of this engine, the Y385, Y395 and Y485. There are three versions of the oil pump. Circle G (Jinma Tractor Parts, Farm Pro Tractor Parts, and More | Circle G Tractor Parts | Chinese Tractor Parts & Supplies) used to have pictures and measurements for all three versions on their website, but I can't find it anymore. When I replaced mine this is what they said:
"See the pictures for measurements as the number doesn't always correspond with the engine."

You may have to call Circle G or Tommy to make sure you are getting the right part.

When I replaced mine, it was the exact same issue, the shaft had sheared off. At first I ordered a replacement shaft. However, they are different lengths for different versions of the pump and I got the wrong length. So I ended up ordering an entire pump assembly. The upside was that the new pump was much better, higher oil pressure at lower RPMs. Apparently they redesigned the pump after a high incidence of failures.


If needed, the front drive shaft can be removed without having to support anything else.

 

[nepa]

Thanks Quicksand. I must be doing this the wrong way. Believe it or not, I took the pump out just by removing the shallow 1 inch deep plate on the bottom of the oil pan. What a bear it was removing the bolt that holds the pump on when you can not see it and have very limited swing of the wrench. The wrench, by the way, had to be ground down to just a shell to work. The front drive shaft did need to be removed. Fortunately, nothing is broken or lost and now I just have to wait for the new parts. I was also mistaken about needing to support the trans as what I was looking at was part of the FEL under the trans.

 

[quicksandfarmer]

Thanks Quicksand. I must be doing this the wrong way. Believe it or not, I took the pump out just by removing the shallow 1 inch deep plate on the bottom of the oil pan. What a bear it was removing the bolt that holds the pump on when you can not see it and have very limited swing of the wrench. The wrench, by the way, had to be ground down to just a shell to work. The front drive shaft did need to be removed. Fortunately, nothing is broken or lost and now I just have to wait for the new parts. I was also mistaken about needing to support the trans as what I was looking at was part of the FEL under the trans.

This makes sense to me. It sounds like you have the version with the 2-piece oil pan. That is specifically designed so that you can switch out the oil pump without having to disassemble the whole tractor. It sounds like you're well on your way. Do make sure that the replacement pump matches exactly the one you have now, it sounds from your description like they might have modified it to make it easier to replace. The first time I replaced mine it wasn't exactly a match but it seemed to fit so I put it in, but when I tightened the fastening bolt I cracked the pump case because it was slightly too long.

 

[nepa]

Well Quicksand, the saga continues. My tractor has a placard saying that it was built in 2004 (I bought it in 2005). The parts manual that came with it has a page from the Editor dated 1996 that says "In compilation of the catalog, due to limited time and level, some mistakes can hardly be avoided, ..." The parts catalog does not show the oil pump as an available assembly which is the only way I could fix it. Not that it would help because the diagram of the oil pump in the parts catalog was totally different from what was in my tractor anyway. This must be really tough for the parts dealers. I, like you, was sent the wrong pump. I have confidence that this will be resolved shortly.

 

[quicksandfarmer]

I feel your pain, it's very frustrating to be hung up on parts.

If you look on the JM Parts website (Object moved) it says:

Please note that there are three variations of this pump. They are marked on the cast housing with either a 380, 385 or 480 marking. This does not have any correlation to your actual engine number, i.e., Y385. This pump is marked 480.

The starting point is getting that number.

 

[nepa]

The broken pump was marked 385 that came out of my y385 engine. Just received a replacement marked 385 and it is a perfect match and will go in tomorrow. The 480 that was sent first would have broken if I attempted to install it. Thanks again for relating your experience.

 

[duttymaxx]

Thanks Quicksand. I must be doing this the wrong way. Believe it or not, I took the pump out just by removing the shallow 1 inch deep plate on the bottom of the oil pan. What a bear it was removing the bolt that holds the pump on when you can not see it and have very limited swing of the wrench. The wrench, by the way, had to be ground down to just a shell to work. The front drive shaft did need to be removed. Fortunately, nothing is broken or lost and now I just have to wait for the new parts. I was also mistaken about needing to support the trans as what I was looking at was part of the FEL under the trans.

I am in the same predicament as well with my oil pump, do you by chance have a picture of your wrench? Or can you tell me which way it was ground? Did you grind it thin? Did you shorten the fingers? Did you have to cut the wrench in half? Any help would be greatly appreciated.

 

[JD1549]

Thanks Quicksand. I must be doing this the wrong way. Believe it or not, I took the pump out just by removing the shallow 1 inch deep plate on the bottom of the oil pan. What a bear it was removing the bolt that holds the pump on when you can not see it and have very limited swing of the wrench. The wrench, by the way, had to be ground down to just a shell to work. The front drive shaft did need to be removed. Fortunately, nothing is broken or lost and now I just have to wait for the new parts. I was also mistaken about needing to support the trans as what I was looking at was part of the FEL under the trans.

This is an old thread. but I hope someone can help. After fighting with that bolt, I - with Tommy's help - made a wrench
and got the bolt out. Now there is nothing holding the pump in, but I cannot budge it! According to the parts diagram,
it should pull down from the hole in the block. I am totally stuck. Maybe it is a "force fit" and needs the 500 pound
gorilla to pull it out??? Any help would be GREATLY appreciated!

PS here is a pix of Tommy's wrench that he sent me. My cheep (fat) wrench also had to have some metal ground
off the box to clear area around the bolt head. Hope this helps if you find yourself in the same fix......
cheers,
johnd

 

[mmprestine]

When I replaced all the lower end bearings in my engine I dont recall having an issue with removing the oil pump. I believe there is a bolt on the inside that has to come out.

This is an old thread. but I hope someone can help. After fighting with that bolt, I - with Tommy's help - made a wrench
and got the bolt out. Now there is nothing holding the pump in, but I cannot budge it! According to the parts diagram,
it should pull down from the hole in the block. I am totally stuck. Maybe it is a "force fit" and needs the 500 pound
gorilla to pull it out??? Any help would be GREATLY appreciated!

PS here is a pix of Tommy's wrench that he sent me. My cheep (fat) wrench also had to have some metal ground
off the box to clear area around the bolt head. Hope this helps ifView attachment 608819 you find yourself in the same fix......
cheers,
johndView attachment 608819

 

[quicksandfarmer]

"Disconnect the oil pump outlet pipe from the engine block, it's held by two 13mm bolts. The oil pump is held by a single 13mm bolt. Once the pipe and the bolt are off it just slides down. Remove the two 13mm bolts that hold the outlet pipe to the pump."

Have you disconnected to the oil pump outlet pipe?