I have been having a mysterious coolant leak for a little while. I put a hose clamp on the overflow already but that was not the issue. I havent changed the radiator cap but it doesn't look like there is much if any coolant leaking from there. I have no puddles under the truck ever. This morning I opened the hood to check it out and this is what I found. The whole back of the motor is coated. I dont think this looks good but how do I trouble shoot from here? No smoke, runs fine.

 

Try washing it down as clean as you can get it and let it dry then run down a few blocks until its warm pull over with a flash light and take a look its had to tell from just pictures and it looks like it leeks under pressure. Or if you have a way to pressure up the rad after you wash it down???

 

Ok. Ill go wash it down now. Where could I get a radiator pressure gauge? How much are they?

 

http://www.harborfreight.com/radiato...kit-69258.html
here is a example

 

I think I found what was all over the back of the motor. I already ordered a new crankcase filter. I don't think this would cause a coolant leak though?

 

Autozone will usually loan you one for free. You give them $80. When you bring the tool back, you get your $80 back. Other parts stores in your area may have the same deal.

Finding a leak is often a challenge. After the engine is warm, hose it down good with hot water, and then let it dry. Blow some corn starch around potential leak areas - like the thermostat housing and upper radiator hose - and then run the engine. The corn starch will turn dark when exposed to liquids.

After you find and fix the leak, corn starch is easy to clean up.

 

Are you sure it's coolant that's leaking?? Most times a mess like that around the valve cover is either oil or fuel. Like stated, give it a real thorough cleaning and go from there. Keep us posted.

 

It looks green. Do you have the correct coolant in there? Isn't it suppose to be pink?

 

It looks like that pipe plug in the back is about to fall out. Wouldn't hurt to put a wrench on it and see. All the stuff on the right hand side looks like just oil. Don't forget about that little hose under the exhaust manifold when you start looking for leaks, it has been known to leak.

 

Good idea, never seen that one before.

 

Ill try the corn starch trick. Great idea!


I took it for a ride this morning and here is the only spot coolant showed itself. I'm pretty sure it's coolant. It's neon green. It seems to be showing up around those lugs? What are those lugs exactly?

 

I am guessing that you wanted to type "plugs"? Those plugs are coolant passages in the head, they are just like the one with the nipple in it for the heater core. They will have coolant under them.

 

I did mean plugs, thank you. Is it possible that I just need to reseal, replace? If so, what would be the process to do so?

 

Teflon tape or pipe dope works well. Pipe threads have a taper so they will get tighter as they go in. I would try to snug them up first and see how that goes. If they still leak pull them out and try the teflon tape. If you pull them out you may loose a little coolant, not much as they are very close to the top point in the system. A 3/8 ratchet or extension will fit in those plugs.

 

My 06 had a leak on the small pipe right at the firewall, near the back of the valve cover, on the passenger side, loose clamp, has done it twice now, vibration and expanding and contracting seems to do it.