So the other day my 1990 fj62's thermostat went out. the engine got hot but it never went into the red, only right below the 3rd mark. It did however get hot enough to blow a hole in the radiator. i replaced the thermostat and took the radiator to a shop to get repaired. I put everything back together and drove it for about 25 minutes without anything happening. I parked it and let it sit for 45 minutes and then came back to check it. while it had been sitting it leaked out a decent amount of coolant but was not leaking when I got there, it was just a puddle. I turned the car on and it was fine for a few minutes and the the check engine light came on and it started leaking a steady stream from somewhere, but I couldn't tell where. I turned the car off for a few minutes and then back on again and no check engine light or leak. drove it around for 10 minutes and parked it; no leaks anywhere. I let it sit again and came back; still no leaks. I'm super confused right now; could it be a cracked head or blown head gasket??? there is no water in the oil.
fj62 mysterious coolant leak
- Thread starter Isaiah56
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- coolant coolant leak fj62 leak
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LAMBCRUSHER
SILVER Star
could be water pump, leaking hose clamp or rad shop overfilled overflow can and normal expansion drove excess out of bleeder hose. but I'd verify that if I could...
When I did my thermostat I was suppressed how tight the top rad hose had to be so it didn't leak. Would not leak until the thermostat opened. Would run down shroud and was difficult to locate at first.
CaptClose
SILVER Star
+1 on the overfill. Same thing happened to me when I replaced the radiator. I overfilled it. I thought I burped the system pretty well, but I still had some overflow from the reservoir for the first week or so.
The pressure in the cooling system increases immediately after you park and shut the engine off, because there is no fan or airflow to help cool things down. That pressure will force coolant to the reservoir and if the reservoir is already full, it will spill out the overflow tube. Nothing to worry about.
Like @LAMBCRUSHER said, verify this and be a boy scout, carry some distilled water or extra coolant in your truck for the next few weeks, just in case.
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I have checked all the hoses that i can see without removing anything and they all look fine. All the water is dripping off of a metal hose that runs right in front of the oil pan. It coming from above that but I cannot tell where. Its not the overflow tank, I took out the radiator myself and brought it to the shop and filled the whole coolant system back up, so the overflow is not too full. What could cause the water pump to fail this dramatically? Wouldn't it start off with a slow leak and slowly get worse if it was the bearing or something?
If your playing with the hoses and clamps, I would highly recommend getting powergrips on amazon in the appropriate size for all your hoses.
These things are AWSOME. Patented for semi trucks they go on and shrink to the correct size when hit with a heat gun. They flex with the climate and ever since I switched over I couldn't be happier. You'll never need to think twice about loose clamps.
I was never a true believer until I got so fed up I caved and tried them. My metal clamps sucked, and in the winter they would loosen up and plague me. Now I have temps in the negative and I don't see a drop. Worth every penny
These things are AWSOME. Patented for semi trucks they go on and shrink to the correct size when hit with a heat gun. They flex with the climate and ever since I switched over I couldn't be happier. You'll never need to think twice about loose clamps.
I was never a true believer until I got so fed up I caved and tried them. My metal clamps sucked, and in the winter they would loosen up and plague me. Now I have temps in the negative and I don't see a drop. Worth every penny
Some sort of debris could have got sucked up into the pump when you put the radiator back in, that's what happened to mine. Some sediment got in and worked its way into the seal. There's small hole in the pump where fluid will leak when it's on the way out
It never rains, it pours....
CaptClose
SILVER Star
I'm not totally familiar with all the anotomy of a 62, but check the thermostat housing to verify everything was snugged up properly. You should check all the bolts for tightness. There's only a few places it can leak from in that area, should be able to find it easily enough. If not, rent a radiator pressure test kit and put some pressure in the system... you'll find where it leaks real fast that way.
Water pumps can just go boom. Nothing was amiss Feb 2 when I parked at work, and that night when I went to start the truck the WP bearings literally fell out. So loose the fan was into the shroud. Turned it over and bang, whack, clang and coolant everywhere. I just got done replacing it tonight so all that stuff is fresh in my head. I'd take your radiator shroud off (and cut it in half horizontally if you haven't done so already, makes life much easier) and get a telescoping swivel mirror and look around at all the hoses and under your WP. You'll find your leak.
I'm not familiar with the layout of a 3fe in a 62 as we don't get them over here . And maybe giving u a bum steer.
But anyways on my 3f .
U have two bottom hoses. Obviously the hose that fits on bottom Rad outlet and runs to the metal joiner pipe. And then the smaller hose from Wp to top of metal joiner pipe. Even tho u wouldn't have removed this pipe. Maybe worth checking that all clamps r snug and nothing was disturbed . As aleak there will replicate a wp leak as well.
But anyways on my 3f .
U have two bottom hoses. Obviously the hose that fits on bottom Rad outlet and runs to the metal joiner pipe. And then the smaller hose from Wp to top of metal joiner pipe. Even tho u wouldn't have removed this pipe. Maybe worth checking that all clamps r snug and nothing was disturbed . As aleak there will replicate a wp leak as well.
you can always use constant toque hose clamps, all the new trucks/semis where I work come with them, all Caterpillar equipment comes with them also.
are the power grips one time use? do you need to replace the hose each time?
@Isaiah56 good to hear you found the issue and got it fixed
