Yanmar Engine Coolant Leak

[GCLL]

I have a 2008 Gator XUV with the Yanmar 3TNV70-BJUV diesel. It only has 116 hours on it and it is slowly leaking coolant. I have noticed random drops of coolant on the floor since new, but it has never been much. It appears to be coming from the water pump. I will have to remove the plastic shroud to be sure where it is coming from on the pump. I assume it is leaking from a wheep hole?

It is a very slow leak, I've never had to add any coolant until now. The last time I used it for snow removal I was out plowing with it for about 6 hours and it was very cold, like -10 wind chill. After I parked it is when I noticed a baseball sized puddle. Maybe since it was so cold out the thermostat wasn't opening, forcing it to leak slowly?

Any ideas? JD will not warrant it, they want $500+ to replace the pump.

 

[normde2001]

Any ideas about what? Replace or rebuild the water pump.

 

[Car Doc]

You may be stuck buying a pump from JD if you want a new pump however on older tractors having one sent in and rebuilt is standard procedure since the internals are similar to other pumps.

Seals and bearings are more standardized than complete housings etc which can be specifically built to say JD specs to fit a certain application etc.

 

[GCLL]

I didn't know if anyone was familiar with this engine and could say that it was common for the seals to leak or the pump to go bad. I'm finding it hard to believe that the pump has failed in 116 hrs. Maybe when I have time to look at it, it will just be the seals.

Is the pump pretty easy to replace? I've done several in gas trucks, but never a small diesel.

 

[clemsonfor]

I didn't know if anyone was familiar with this engine and could say that it was common for the seals to leak or the pump to go bad. I'm finding it hard to believe that the pump has failed in 116 hrs. Maybe when I have time to look at it, it will just be the seals.

Is the pump pretty easy to replace? I've done several in gas trucks, but never a small diesel.

Not really sure if this is a single or twin yanmar engine or how it is really set up. But it is the same procedure really as a car. Never done mine, but looking at it, it will be easier to do the waterpump on my tractor than any gas-engine truck or car i have ever done one on. There is easy to take off sides and the stuff is easy to get at instead of buried under 2 other irrelevant things.

 

[GCLL]

I was able to get the engine cleaned up good and figure out where the leak is coming from. The good news is that my water pump is fine, the bad news is it's leaking from two spots.

It is very slowly leaking from what appears to be the coolant drain plug in the bottom of the engine. This plug takes an allen wrench and looks like a typical oil drain on the bottom of an engine.

Next to this plug there is a 10 MM bolt and it is leaking from here also. I tried tightening both of these and they are tight, but still leaking. I am going to take them out and put some teflon tape on them. Is this suitable for an engine thread or is there something better?

It looks like I will still have to remove the water pump cover and belt to get at the 100 MM bolt with a socket so that I don't round it with a wrench.

 

[winston1]

If it is a tapered plug teflon tape is great. If it is not tapered there should be a gasket or o-ring seal of some type.

 

[California]

For the bolt a copper washer might be the solution. Or if it is semi-permanent, then maybe the removable version of thread-locker paste.

But your teflon tape idea sounds like all that is needed. Just don't wrap it clear to the tip of the threads - to keep fragments from floating away.

 

[GCLL]

Thanks for the help