Leaking coolant

Coolant leaking from valley coming down near water pump inlet. Removed coolant bypass pipe underneath intake manifold. Cleaned flange, mount, and resealed with FIPG. Still leaking! Originally thought it was from water pump even though I had timing belt and pump changed less than 50k miles ago. Went ahead and did timing belt job. Still leaking! Now Im starting to think it's a head gasket? Did compression test results in picture. That was with engine at operating temp. Even tried couple drops of oil down all cylinders, no different. I do have to admit I'm using harbor freight cylinder test kit.

 

Nah. Youll know if its hg. My compression in #2 was 160 psi, and 118 in cyl #3. Missfired, lost coolant thru the exhuast(but can go the other direction and get choco oil).

 

Im not sold on the head gasket as there are no signs other thank leaking coolant and valley filling with coolant. Maybe that coolant bypass pipe had a hair line crack or tiny hole I didn't notice.

 

Yeah hg is very noticable. I even had rough idles on startups when the truck was up to temp, would nearly die out eating all the coolant

 

the coolant passages on the heads where the lower intake sits have a tendency to corrode. You might need a straight edge and put it across the ports on the lower intake and heads and see if light from a flashlight "peeks" its way through.

 

Clean, reassemble, pressurize, watch.

If it doesn't leak under pressure, its likely HG that requires temp and load.

 

Looks like the seals between the heads and lower intake manifold have seen better days. That's probably where it was leaking if no coolant in your exhaust

 

Can I pressurize with intake manifold removed?

 

upper 2 plenum yes, intake manifold no.

 

Did you check the oil cooler hose that runs from the water pump to the oil cooler? Maybe that hose is leaking. Did you renew the intake manifold gaskets? Those could have been cause of the leak of coolant into the valley between the heads.

 

Yes replaced hose that runs from water pump to oil cooler. Cleaned with plastic puddy knife, acetone, and replaced intake manifold gasket. Still leaking thinking I have a crack somewhere

 

Kind of a labor intensive process, but if you clean the oil and coolant residue out of the valley end jack the truck up extremely high in the back and run it long enough to get coolant leaking out, you could maybe see if the coolant is running from the back to the front or if it’s just leaking and staying in the front. If it’s filling the whole valley you could consider it’s coming from the middle or the rear of the engine. Then you could do the opposite and jack the front up and see if it’s coming from either the rear or the middle.

 

When did you switch from red to green coolant?

 

Ha definitely couldn't afford the red with this problem. Maybe once I get this fixed I'll do a flush and get some Toyota coolant.

 

Here'swhat it looks like underneath new gasket that cleaned with plastic puddy knife and acetone the best I could.

 

Red Scotchbrite kills a lot of that stuff.

 

Looks like metal is messed up. Should gasket take care of that or should I put a little FIPG and the gasket?

 

What kind of gasket? Shouldn't matter, but imo the kind with rubber around the passages kind of gets that effect already. MLS maybe could work with a small small small about of FPIG - is it at least smooth to the touch? Little WD40 and scotchbrite could probably erase most of the discolored stuff, but only really an issue once it's enough to be able to catch on your fingernail imo.

 

Scotch bright is helping and yes you can feel the gouges in the metal. Felpro for the gasket brand.