Nortrac 254 injection pump oil overfilled
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piper184
Gold Member
More than likely it is fuel seeping into the injection pump crankcase. It might be engine oil but the odds of that are slim.
How many hours has it been since you changed the IP oil and what kind of oil did you use?
If you use dyed diesel fuel it should be easy to see the dye turn the oil pink.
My tractor had the same problem. I removed the "lift pump" from the side of the IP and found that the lift pump uses a plunger that runs off of a cam in the IP. The only seal between the fuel and the crankcase is a small o-ring. This is a poor choice of how to seal a moving rod and the quality of the o-ring was low. I replaced this o-ring several times with varying types of o-ring material with no success. Finally got tired of the mess and removed the lift pump completely and made a plate and gasket to cover the hole and installed an electric pump to do the work of the lift pump. There is still a bit of fuel getting into the crankcase so it must be an internal leak of the IP pump itself. However now I can go to engine oil change time without it overflowing. I change the IP oil at the same time anyway. There is an overflow connector on the side of the IP. I put a small piece of clear tubing on that so I can monitor the overflow in case it gets too full. Without the tube the oil would drip out on the ground and I would never see it.
There should be a breather on the IP, make sure that is not plugged.
How many hours has it been since you changed the IP oil and what kind of oil did you use?
If you use dyed diesel fuel it should be easy to see the dye turn the oil pink.
My tractor had the same problem. I removed the "lift pump" from the side of the IP and found that the lift pump uses a plunger that runs off of a cam in the IP. The only seal between the fuel and the crankcase is a small o-ring. This is a poor choice of how to seal a moving rod and the quality of the o-ring was low. I replaced this o-ring several times with varying types of o-ring material with no success. Finally got tired of the mess and removed the lift pump completely and made a plate and gasket to cover the hole and installed an electric pump to do the work of the lift pump. There is still a bit of fuel getting into the crankcase so it must be an internal leak of the IP pump itself. However now I can go to engine oil change time without it overflowing. I change the IP oil at the same time anyway. There is an overflow connector on the side of the IP. I put a small piece of clear tubing on that so I can monitor the overflow in case it gets too full. Without the tube the oil would drip out on the ground and I would never see it.
There should be a breather on the IP, make sure that is not plugged.
Thanks Peter and Piper. There is no fuel in the oil that I can tell. I have never changed the oil after a few years of ownership. Thanks for the information. This is very helpful. I will change it and monitor it.
Where is the the overflow where you attached the tube? Mine only ran out when I removed the dip stick.
Where is the the overflow where you attached the tube? Mine only ran out when I removed the dip stick.
piper184
Gold Member
It is a little hard to see in this picture. This was taken when the hand primer/lift pump were still on the IP. The overflow tube had a rubber cap on it but if you take that off of the little 90° nipple that is the fill level indicator on my pump. Mine does not have a dipstick so it may be different than yours. To fill this one you remove the breather cap and pour in oil until it flows out of the overflow tube. Then let is sit for 10 minutes to let everything settle then replace the rubber cap.
When I found mine was overfilling, I put a short hose on the nipple and ran it down into a collection bottle so I could keep an eye on it.
When I found mine was overfilling, I put a short hose on the nipple and ran it down into a collection bottle so I could keep an eye on it.
254OZ
New member
I have a similar problem on my Jinma 254. The IP has two drain plugs and when I drain the oil on mine it is mostly only the oil from the drain nearest the rear of the tractor that seems to be extra thin. I was changing the IP oil when I do the engine oil (at 100 hour intervals) but since I realised there was a fuel thinning problem I have started to do the IP oil at 50 hour intervals.
A couple of years ago I added a short length of clear plastic tube to the overflow so I can keep my eye on the problem and it doesn't really seem to be getting any worse. The amount of oil that comes out doesn't seem to be directly related to run hours but does seem to be connected to the number of warm up cycles the engine does.
This is the short blocked off pipe I added to the overflow. I just empty it when it gets full.
A couple of years ago I added a short length of clear plastic tube to the overflow so I can keep my eye on the problem and it doesn't really seem to be getting any worse. The amount of oil that comes out doesn't seem to be directly related to run hours but does seem to be connected to the number of warm up cycles the engine does.
This is the short blocked off pipe I added to the overflow. I just empty it when it gets full.