TyneeGX

Has anyone repaired a coolant leak under the intake? I just repaired the bad o-ring and rtv at the front coolant bypass joint. But, there is still active coolant leaking around the back side of the block and puddling on the garage floor beneath the front of the transmission each night.
So, I'm guessing I need to start removing the intake to hunt this thing down, the top of the block, just under the intake is constantly moist. But I'd like to have a list of seals and parts I'll need to replace before I start.
Anyone solved this before?
Thanks all.

chiph9

Have you done a cylinder leak-down test to check for a blown head gasket?

Chip H.

TyneeGX

No, I'm cautiously optimistic that isn't the cause. The coolant doesn't "disappear", or get burned off, it just leaks onto the floor. The engine doesn't overheat, since I've had it, it does not get hot, stays right where it should on the gauge, correct operating temperature. I just changed the oil last week, and it looked fine.
Is there anything I'm missing that would indicate a bad head gasket?

I'm guessing that since the coolant got low due to the other failed o-ring at the front bypass, that some other old seals/O-rings may have had a chance to dry out, and are now weeping.
Fingers crossed.

And like I said, there is a wet spot on top of the engine, above but behind the front bypass joint, that's why I guessed its something just under the intake. Wouldn't the head gasket be lower down underneath the lower intake manifold?

Shooting in the dark..

TyneeGX

ignore the leaky bypass joint to the left of the arrow, that's the O-ring and RTV I just fixed, those spots are dry now.

neub

neub

Okay. My apologies for a feminine magazine cover but I didn't want to put glycol covered parts on the counter top so I grabbed wife's old magazine from recycling. Please pay attention to aftermarket vs oem o ring quality. The aftermarket one is maybe a year old from the previous owner when he did the timing belt job. He used a garbage water pump that called for a FIPG. I think you should replace oem with oem.

So..is your issue the same as mine? I don't know but I had a puddle of coolant in the valley (bw cylinder banks). That 99 cent o ring was busted. It felt like plastic when I removed it. It took me six hours to get to it. It's at the water pump outlet underneath the intake manifold, right on the heater pipe.

Edit: I also found the water pump to be leaking in multiple places. You should not use FIPG anywhere around the water pump. That Glycol based super long life coolant is super corrosive to black FIPG. I hear grey is marginally better but you should just buy an oem water pump that comes with proper gaskets. So that's my suggestion - do the water pump job and replace everything. If you've recently done this replacement - check what parts were used unless you Did it yourself.

TyneeGX

Dang, that might be it. What part number was that oring? The other one I replaced did the same thing, felt like plastic. I think I'll try to dig in and replace that oring too, and if she still leaks, I'll have a shop verify if the pump needs replaced.

bbrowncods

Your arrow is pointing directly to the "Coolant Bypass Hose" that connects to the underside of the throttle body. Remove the air intake hose and then the throttle body (nut and three bolts) to get a better look.