I'm stumped - coolant leak
 

So with the severe cold temps, i've had an issue that I can't seem to figure out.

We had a water pipe break in the house. I had gotten that temporarily fixed, but I needed to make an emergency run to Lowes. When I went out to the truck, I noticed drops of something on the ground under the engine. It appeared to be maybe coolant. I was in a hurry to get to Lowes though, so I didn't give it much investigation, and since it was just a few drops I figured it was probably nothing too serious. When I got about a block from the house though, I noticed something making a weird noise (squealing like noise). I turned back around and went back home. I looked under the truck and in addition to the few drops on the ground, the entire underside of the engine was coated with antifreeze.

So today it warmed up to single digits, so I went out to see if I could figure out where it had come from. There is so much coolant everywhere, there is no way to tell for sure were it is coming from. My guess was a freeze plug though. So I washed off the underside of the engine and let it dry. I went back out and inspected the freeze plugs. The three on each side of the block look normal (though it is very difficult to see the ones behind the motor mounts, but they look fine and are dry), and the ones on the front of the motor also seem normal. At this time, there is no new anti freeze anywhere. I ran the truck for awhile, and even drove it around the block several times. Bottom of the engine is still completely dry, no new antifreeze.

At this point, i'm thinking it might be something with my water pump. That might explain the squealing noise I heard, and perhaps it is leaking out of the weep hole or even the gasket. What is stumping me though is that there is no leak now. What would leak only when it is very cold? Freeze plug still comes to mind, but like I said, they all apprear fine.

Any ideas?

i would say water pump, or by pass hose,, sum thing that is in the front on the motor to get the hole motor wet,,,, with the fan and the air blowing throw the rad would put water every were



hell you wanted to do the t-chain any way

I can't say I was really "wanting" to do the timing chain, but it is something that has been on my mind to replace since I turned 100k. Not a job i'm looking forward to though.

Only the underside of the motor was wet. Also the front axle and most of the suspension. The top of the motor was dry, and there was no clear evidence of leaks from around the water pump, thermostat, intake, temp sensor, or any other place you would expect to find coolant coming from on the top end. But it could have been running down and then dripping and getting blown back when I drive I guess.

How's the rad return hose looking? Check the clamp down by the WP, and also check the heater return hose.

I've seen an antifreeze water mix that can get slushy, and in that frozen state push out through seals and hoses until things warm up completely. That'll cause a squealing fan belt either from antifreeze imersion, or one slipping on a half frozen water pump. Or both :(

What is your antifreeze mixture rated for...and have you checked it with a ball tester.

EDIT: went and checked my "jug o' freeze" 50/59 mix which says it's good to -34f.

I'll test my mixture tommorrow. It's possible it might be on the weak side I suppose.

Is your overflow bottle still full? Maybe it came from that, and once it drained out you no longer have a leak?

Not full, but still above the add line. I checked to see if it was leaking, and it did not appear to be.

Well, sounds to me like you have a doozy on your hands. Why is there a law that says this kinda stuff has to happen when it is a thousand degrees below zero?

Maybe the wife will be kind enough to let ol' silver sneak in and stay warm in place of the Aspen :icon_duck:

my son's honda used to leak around the water pump seal only in cold weather. below 20 or so and they'd be a wet spot of antifreeze and a drip. above 20-ish and it would be dry. it did it for a couple of years before i got nervous enough to change it. it never got worse, but just stayed the same.