Yanmar ym 1720 Coolant in oil - have a few questions.

[wyndsurfr]

Hey folks, just added a little ym 1720 to the fleet here on the farm, got it and a trailer full of implements for a ridiculously low price from an estate. Friends of mine, the father died so no one knows anything about the tractor they sold me.

I'm a pretty good mechanic, so don't worry about getting technical but I do not have a manual for this critter yet so I may not know the names of certain components...

anyhow, first things first. Has coolant in the oil. Engine does turn with a wrench but I only turned it a little bit to make sure it wasn't locked down. Instantly you want to think, cracked block or head or head gasket is bad... But, looking at this thing, the water pump is gasketed to the head and has a main water line (1.5 inch) going down to a part that is gasketed to the block (like a timing cover would be on a car engine) and the oil filter screws into this same part... I'm wondering if this could possibly be the culprit. It does NOT look like the tractor was ran like this since the coolant/oil are not mixed at all. This part that the oil filter screws into and has a main water line going to (front of the block) has permatex gasket sealer squeezing out around it so... I'm hoping that this has just went bad sitting there and leaked water into the block... I do not know the last time the tractor was operational but seems to be in fairly good cosmetic condition so I'm hoping it was taken care of... I'm in no super rush to fix this one, we have two on the farm now anyhow but of course when you get a new toy you want to start tinkering haha...

anyone familiar with this engine care to weigh in? This is a 3 cylinder with a water pump by the way....

Thanks!

 

[normde2001]

Could be. Hard to tell from here.

 

[wyndsurfr]

hahaha, what you can't psychicly diagnose a tractor engine from a distance? I was just curious if this was a possibility with this thing

 

[normde2001]

I don't believe there is any connection between water pump and crankcase other than cracked block. You need to get it running and troubleshoot.

 

[wyndsurfr]

what I am specifically referring to is below the water pump is a part that is bolted and gasketed to the front of the block, the water pump output goes to this part and the oil filter also screws into this part.

 

[wyndsurfr]

certainly not discounting the "normal" things like a cracked block/head/head gasket, just that this part that takes both the output of the water pump and the oil filter into it looks like it could be a culprit, wondering if anyone knows what this part is and if a bad gasket here would lead to the radiator dumping into the crank case.

 

[winston1]

I think you are referring to the gear case. I have not heard of a coolant leak into the crankcase at that point. I would say 95% of the Yanmar coolant leaks into the oil are from blown head gaskets. These engines do not take over heating well.

 

[normde2001]

How sure are you that it's coolant? Was tractor sitting outdoors.

 

[careyo63]

I would start with useing one of these. You can most likely Rent one from a big chain Auto Parts store. It will help detect where the leak is by pressure readings and Certainly start to point you in the right direction. I've Used one quite a few times over the yrs. on auto cooling systems. If you buy it there will be instructions on how to use it and what to look for esp. if it's doesn't show up with a visible leak. Read the Description of it. Radiator Pressure Tester Kit

 

[wyndsurfr]

thanks careyo, that was going to be my first step to see if I can hear it leaking anywhere. Yes, I am quite sure it is coolant, it is yellow tractor was parked under a shed with a jug over exhaust... I am quite sure it is not the gear case, the part I'm talking about is on the front of the engine block, I'm hoping that is the issue and not a cracked block... Head gasket I can deal with, cracked block or head and I'll probably just start parting this critter out since I was told it needs a clutch and lift repair as well.

I'm not certain at this point how I could tell if it was leaking at this weird cover on the front of the engine or coming in through the head gasket other than to pressurize the radiator and hope I can hear it hissing/bubbling somewhere... wish me luck!