Coolant leak in my 03' ranger v6 4.0

[croadmar]

thought it was my water pump, replaced that and my thermostat, and still have the same leak. it's leaking alot of fluid (probably a gallon a minute) from above and behind the water pump. by reading posts i'm finding it may be an old freeze plug, lower thermostat housing, intake manifold gasket or a head gasket. will a pressure test of the coolant system tell me the problem, if so, can someone please lead me to the correct steps to do so.

Thanks

 

[88_Eddie]

you'd have water in the oil or oil in the water if it was a head gasket, did you use sealant when you put the water pump back in?

 

[croadmar]

i sealed both sides of the water pump gasket. the water pump area and thermostat cover was bone dry when i started it up after changing it but coolant was leaking all over behind the pump somewhere. how do i get back there to see the actual leak?

 

[adsm08]

that is a lot of leak. Only a few things can leak that much, like a burst hose.

 

[88_Eddie]

that is a lot of leak. Only a few things can leak that much, like a burst hose.

i hope that would have been one of the first things he checked

can you post pics?

 

[adsm08]

i hope that would have been one of the first things he checked

can you post pics?

Same here, I just can't think of anything else that could leak that much without being obvious about it. I mean 1 gal/min, its only a 3 gallon system.

 

[croadmar]

didn't see any hose leaks, but again, i can't really see the area without starting to tear off the top. i'll try and dig around the hoses
picture a v6 4.0 with coolant leaking all over the motor and tranny behind and above the water pump

 

[88_Eddie]

i've never really torn into the 4.0 in my exploder, so i'm not really sure where everything is located and what it looks like. i wonder if the block could be warped

 

[PARTSDEV]

Check your lower t-stat housing.i work at a ford dealer-sell em all the time.sorry to say,bad design.

 

[Clay Lorance]

Check your lower t-stat housing.i work at a ford dealer-sell em all the time.sorry to say,bad design.

What he said, had the same problem with mine about 3 months ago, thermostat housing probably has crack in th seam where the to halves meet.

 

[snake]

If you need to pressure test it, turn your compressor down to 20 lbs and shoot air into the coolant recovery tank's hose- that is, disconnect the hose from the tank, shoot air towards the radiator with the rad cap on in closed position. The cap will allow the air in and won't let it out. Be careful not to shoot more than 20 lbs in there or you'll blow the dogcrap out of something expensive. The redneck rad tester works everytime.

 

[croadmar]

thanks for all the info guys, I will try to pressure test it and check the thermostat housing seals. I checked the oil and didn't see any coolant or milky coloring.

 

[croadmar]

it was the lower thermostat housing. finally found time to diagnose and fix it today. Thanks for the help

 

[Clay Lorance]

No problem, that seems to be a common problem on the 4.0s. Glad to see you got it fixed.