I've got a 4.0 OHV and for some reason, I've been finding two small puddles of coolant under my truck in the morning. I took it to the dealer and had them pressure test it and they said they couldn't find a leak anywhere. I thought it might have been something with the really cold weather at school contracting a gasket or seal or something but now that I'm home and its a little warmer and still leaking, I'm running out of ideas. I wrenched down on the bolts on the thermostat covering yesterday but when I came out this morning, something was still leaking. I snapped a few pictures althought it might be hard to see where the coolant is standing on the engine, I'll try to point them out:


The front two puddles are most recent


Drivers side of the engine, look for the glossy and dark areas in the center


Passenger side, glossy area in the middle, fair sized puddle


Picture of the thermostat housing

 

Well, I see it scoming from the water pump in that lower picture... Could be coming out the weep holes, althbough on the OHV I'm not sure if its where I think they are or not..


I'll let someone with experience in the OHV motor lend a little more help then I can.

 

It's more than likely the water pump seal.

Look for evidence of green / white residue on the bottom side of the water pumps snout. There is a little hole that it'll be coming from if that's the problem.

If so.. gotta replace the pump.

Rich (OEM water pump engineer for 6 yrs )

 

Now see I am having leaks also...but pressure is fine..and mine isn't leaking as bad as taht..but I still smell it everytime I cut the truck off and I do lose a little from the resevoir every week or so...Im lost also..

 

Mine is doing the same thing as described above, got under the vehicle and found it coming from the water pump seal. Gonna take it off and replace with Fel-Pro seal that has silicone bead on gasket.

 

based on that last pic, I would say it's the o-ring that's around the thermostat. Have you changed your t-stat and not changed the o-ring?

Anyways, It gets compressed, if it's high miles I can see it leaking. A new t-stat and o-ring should be less than $10. And it's about a 20 minute job. Alot easier than pulling the water pump if your not positive that's it.

 

Well, I just went out to check for leaks today and there weren't any at all. I checked the reservoir too and it was at the same level. I'm guessing that cranking down on the thermostat housing bolts did it and the continued leak was from coolant that was still standing on the block that dripped down when I had parked it. I checked the snout and the seal around the water pump as well just to make sure and I didn't see any fluid leaking from either of those areas. Thanks for the input.

 

Mine is doing the EXACT same thing....No Leaks, when i SHUT THE MOTOR OFF theres a very strong odor of anti freeze and every 2 weeks or so i go through about 1/4 gallon or so of anti freeze, and again NO leaks what-so-ever

 

Watch your exhaust pipe when you start it up first thing in the morning. For that matter every time you start it. Yours sounds like a Head Gasket.

****

 

I had 2 OHV's and both had these problems. On both trucks I found the leak originating from the passenger side head near the firewall, most of the coolant getting burned off before getting to the ground, but it left a nice green/white stain so I could find it.