Coolant leak

[coxster]

Hello all. I have a coolant leak which is somewhere above the water pump. It only leaks when the engine warms up. I've checked the coolant expansion tank and I don't see a leak anywhere around there. Is the only possibility the coolant inlet pipe aka water pipe aka Engine Supply Coolant Pump Pipe? I can see coolant leaking from the circled area above the water pump. Background: Had a catastrophic failure of the coolant outlet hose so that's been replaced (made sue it's not leaking from here). Also replaced the thermostat to water pump hose as it was in a bad way. Also replaced the coolant expansion tank cap as the plastic was starting to disintegrate. Thanks for any help.
Jason

[Dackelone]

Just because it's a new part doesn't mean it's a GOOD part.

To me that looks like your water pump is leaking at the plastic flange. Should be covered by a parts warranty - No ? That white residue on the big coolant hose looks like where the coolant is dripping down and off the hot pump. Probably just a pin hole leak right now.

[ianc]

Yes, you can see a drop of bluish coolant on the hose clamp near the screw head...

ianc

[coxster]

Dackel and Ian - thanks for your responses. While the engine is running, I can see coolant dripping from the area above the water pump (unless the circled area is still part of the water pump? It's a few centimeters above the top of the tstat to water pump hose). I've checked the coolant outlet hose that I replaced and verified that no coolant is dripping from that. Do you know if the coolant inlet pipe connects more or less above the water pump?

[ianc]

It's really tough to say. The circled area is not part of the coolant pump. The pump inlet is the large hose in your pic, the outlet is above it at a 90' angle. If you have coolant dripping from there it could be any number of things: leaking from an upper radiator hose, squirting sideways under pressure from the pump outlet? The thermostat? Very troublesome and tight area to troubleshoot. I would probably just ensure all the coolant hose clamps you can see are tight (but not overtight!) to begin...

ianc

[coxster]

OK, thanks for the help - this is fixed. It turns out that the o-ring on the coolant gasket hose had been pinched during installation so that, even though the two bolts were tight, there was a slight gap on the underside of the hose where it was not sitting flush. I borrowed a borescope which really helped find the source as it wasn't noticeably leaking from there.

Now it's time for the MHD tune...

Thanks again!

[Dackelone]

Originally Posted by coxster

OK, thanks for the help - this is fixed. It turns out that the o-ring on the coolant gasket hose had been pinched during installation so that, even though the two bolts were tight, there was a slight gap on the underside of the hose where it was not sitting flush. I borrowed a borescope which really helped find the source as it wasn't noticeably leaking from there.

Now it's time for the MHD tune...

Thanks again!

Thanks for updating this thread. It just might help other forum members for future repairs.