Does coolant degrade RTV?
('03 RT 5.9L, +120K miles)

Engine light came on today. Stuck my head under the hood for a quick visual, and got a good whiff of hot coolant (actually smelled it as soon as I stepped out). Saw nothing obvious until I got underneath and saw coolant drip off the tranny/torque converter cover (see pic009). Traced that forward along the oil pan lip, up the timing chain cover (?) to the water pump and found two bolts a little loose (not finger loose, but certainly less than the 30 Ft-lbs spec'd in Haynes), and what I am assuming is a source of the leak (see pic008). While cleaning everything, I had a good bit of what I assume is RTV from the chain cover/ block seal, clump up and fall off. It easily smeared like right out of the tube.

I've seen a few threads here with a similar drip from the tranny housing (leaky D, have a look, and others), so I don't disclude the possibility that the coolant is leaking elsewhere as well. Found it odd that it made it all the way down the oil pan the tranny w/o cooking off or evap'ing.

So 3 questions come to mind, if you'd care to share your thoughts:
1) Did I correctly ID that RTV seal as the timing chain cover/block seal?
2) Could the coolant have damaged the RTV/seal significantly enough to open the seal and trigger the idiot light?
3) and what's the liklihood of the coolant making its way down the oil pan to drip off the tranny, even after a 25 mile SoCal freeway commute.

 

yes you did for question 1 no it shouldnt affect where its pressed together and sealed you should be fine or you would see oil leaking for question 2 and yes it would do that for question 3 from the force of the fan pushing it back along with wind if it keeps leaking around the bolt loosen it and put a little RTV around it and tighten it up

 

+1
Coolant is tolerate to high temperatures, therefore it won't evaporate easily, allowing it to travel down to wherever it wants to.

 

Leak continued overnight, into the morning, about a drip/30 secs. It appears coolant passed from the block into the water pump-bolt hole and out the front seal. Removed the water pump and found no evidence of RTV on the seal or bolt threads. . . .this is a re-man pump, installed in Shamrock, TX, when the previous one failed on my Sept roadtrip.

Seems odd the drip continued well after the engine is cold and all pressure should have dissipated. Path of least resistance would be back into the pump then into the radiator/overflow. Oh well, fluid dynamics is beyond me.


Next step: remove chaincase cover and inspect/replace seal. Other than the check engine light, there's no evidence of coolant in the crankcase. About a 1000 miles early, but the oil will have to go anyway JIC.

Let me know if you think I'm missing something.