Mysterious water leak?.?

[thegipper]

Can you take a pictures of where you think the leak is and post it on here? Off the top of my head, I can't think of what sensor you're talking about but maybe it's a coolant temp sensor?

Make a few posts (go in some build threads and tell us how beautiful our trucks are) so you can post pictures and have full access

 

[TheDurk]

So im kinda new here and id didnt really know how to go about asking since i cant really post and you seem like you know a thing or two. I have a 2002 toyota 4runner and a leak that is coming out of what looks like a sensor located below the thermostat but after searching the web i cant figure it out any clues or help or other threads that would address this?

Listen to the guy above and post a pic. Below the thermostat is the Crankshaft Position Sensor. But to tell where the leak is from, we need to see where the pink (or green) crusty stuff accumulates. I really don't think that particular sensor can leak, as it is not in liquid at all.

 

[muellernautique]

Exact same leak as Mikey. Leaks only when the engine is off and cold. When it is running, everything is fine otherwise.

Good thing I noticed today before I started driving. I saw a puddle of antifreeze and found the general area of the leak and then checked my level and after I took my cap off the whole cap broke into several pieces and the spring is now lost in the upper part of my radiator...nice. I'm thinking my plan is drain everything out and pull the radiator and shake it upside down and hope I can get the spring out. Is it possible it could have gone down the radiator and the lower hose and now it is jammed in front of my thermostat?

Okay...back to the leak. Steady drip when the engine is off and cold. Looks to originate from the thermostat neck/housing and then drips onto where the dipstick terminates and then drips down the oil pan slightly further back. When we bought the truck we pressure tested the radiator and coolant didn't blow out of the head gaskets nor were any visible leaks present. The sticker on the front cover shows that the timing belt was replaced at 109K and I can only assume the water pump is the same story. But does this sound like it could be the water pump? I was reading elsewhere and it said the water pump generally leaks on the other side, not the drivers side. Will go take some more photos soon and post them up. Would like to compare with Mikey and see if we've got the same problem going on.

 

[IsaiahC]

I'm surprised no one has mentioned intake manifold gaskets I had a mysterious coolant smell/loss for years and when I took off the intake manifold, there was a GIANT puddle of coolant sitting between the manifold and the engine block. Manifold gaskets were in pieces...

 

[cfb2702]

water pump

So im kinda new here and id didnt really know how to go about asking since i cant really post and you seem like you know a thing or two. I have a 2002 toyota 4runner and a leak that is coming out of what looks like a sensor located below the thermostat but after searching the web i cant figure it out any clues or help or other threads that would address this?

Sounds like the water pump. Had the same symptoms, thought it was the thermostat. Get on Youtube and watch Timmy the Toolman's video on water pump and timing belt replacement. It's here on the forum too. You can do it if you've got the tools and the time. I just did mine. You get a huge sense of self satisfaction after doing something like this and it bonds you with your truck!

 

[muellernautique]

Sounds like the water pump. Had the same symptoms, thought it was the thermostat.

Damn that's what I thought at first too. Hoping it was the thermostat seals or the neck like in my Miata. Well I guess I'm gonna take the front cover off today and pressurize it and see if I can see leakage. Was hoping it was something cheap and easy :/

 

[cfb2702]

Actually, the parts to replace the water pump, timing belt, seals (cams and crank), belts, and thermostat aren't too bad, about $250 from aircabinman on Ebay. I was fortunate in that I had another vehicle to drive while working on mine so I was able to take my time and do all this plus the valve cover gaskets and spark plug seals at the same time. Those parts were about another $50. Go with Toyota parts (Aisin, Mitsuboshi, etc.) if you decide to do it without the seals, etc. I just did all of it at once because I was already in there and had everything disassembled. I've got just shy of 250k miles on the truck and although I had the timing belt replaced at 180k and it was still in good shape, I decided just to go ahead and do rather than running another 20k and realizing I needed to do the timing belt again. I will do it again in another 100k miles if I don't expire before then...

 

[Kotrin]

Haven't been on the site in awhile. Spent a few weeks in the hospital and finally started driving again in January. Saw a like to a post in here so figured I would read and respond. So from what I remember the slow leak ended up bring my rear lines to the heat. It jad small holes which I used some spray and never had an issue till I had to sell it. Driving a manual tends to lead to Hospital visits...

But this did fix my problems. After i fixed it put another few thousand miles on it, lifted, beat it and more no leaks

If i can provide more insight i would be glad to offer what I can.