I've been chasing a small drip for a while. Thought it was the lower hose flange, then the lower hose clamp, then the weep hole on the pump. Can't find any of those leaking from what I can see. I've been crawling around looking..... a lot ! It has the symptoms of the lower hose flange but that is staying dry.

The leak is evident at cold start up and is intermident. Only does it when it wants to. It did it today when the truck was on high idle and hissing like a snake. It's not much, just an spoon full or so. Seems to stop when the truck warms up or evaporates. Coolant tank hasn't gone down to "minimum" and this has been going on for several days.

There is a large steel pipe that runs from just above the block heater towards the front of the engine, below the exhaust manifold, and stops right above and behind the lower hose flange. It kinda looks like exhaust pipe. At the very front of it is where the coolant seems to be leaking. What is this pipe and is there a way for coolant to leak from it or where it goes back into the front of the engine? The way the fan blows stuff around you never know! Hope everyone has the best holidays ever !

 

That's the oil cooler that you're talking about and yes it can leak coolant but I've never heard of one leaking externally usually it leaks oil into the coolant. but I dont know much about the coolers really so I could be wrong I'm sure someone else knows more.

 

Thanks for the ID on the pipe. It doesn't look like something that would leak coolant to me but around the front of it seems to be where coolant is coming from. Just a few drops, not a strong leak. Maybe it's spraying up there from the flange or lower hose somehow. It has me stumped that's for sure. I'm s hoping somebody might have a clue I hadn't checked.

There's no sign of collant in the oil or oil in the coolant. That's the good news ! I replaced the squeeze type clamp with a screw type and figued that could have been it. No joy. Maybe somebody will come up with some things for me to try. I just can't see anything around the weep hole or the pulleys below it. It might be fooling me but I don't think so.

 

What you could do is pressure check the radiator while engine is cold.High pressure wash first then check for leaks.

 

Pressure test cold is the only way I think I'll find it, you're right. I have the means to do that and will do that after the xmas crowd dies down. Truthfully, I just started getting serious with it this morning. I hadn't thought about a cold pressure test.

The truck isn't a daily driver so I'm not up against the wall or anything. I'll find it and fix it ! It won't win.

 

See this THREAD. Post 13 and 14

 

Payton,

Thanks, that helps a lot. I hope I'm wrong about my leak and it turns out to be the flange or the pump ! The pictures were great and a lot of help. I've been trying to to "picture" how coolant could be coming from that area if it's not blowing up there. Got any more wisdom? What all has to come out to get to that thing? It's mighty tight up in there. Does the pump have to come out or just the lower flange? Is this a common failure point?

Wouldn't you know it, just put in new coolant about 2 months ago. I'll just look at it as another flush.

 

I have never worked on the oil cooler.

Go to a radiator shop and have them pressurize your cooling system to find the leak(s).

Powerstrokeshop has a gasket and o-ring kit. LINK

Capture the coolant in a cuople of clean buckets and filter it through a coffee filter and re-use. That's what I did when I replaced the water pump.

 

Robin,
Thanks. I have a buddy with everything needed to pressure test. I'll do that then know for sure. I appreciate the link for the parts needed. I'm gonna jump on it and fix it. Again, thanks for your help !

 

Your Welcome Bob. Good Luck and have a Merry Christmas.