Dumb question - Valley Leak (1 Viewer)

[Dan Lee]

Hi - I'm mechanically challenged. This valley leak that seems prominent, from where is the coolant leaking into the valley? I've seen mention of manifolds and heat exchangers. Are both of these possibilities leading to coolant in the valley? Or is the leak really from the heat exchanger and the manifolds need to be removed in order to fix the leak?

Please help me understand (somewhat urgent) what part of the engine is really leaking and what needs to be fixed.

Thanks!

 

[linuxgod]

It's where the heat exchanger meets the top of the block, underneath the intake. There are pics in this thread. Everything has to come off the top of the engine.

Kind of "Mystery" Coolant leak back of engine (heat exchanger valley leak)

It's most likely the culprit. I had to put a borescope from the back of the manifold to see the pink crust. You do not need new intake gaskets for this job. Two Orings and the proper FIPG. Borescope came in this morning. Confirmed the leak. Passages side front: Passenger side looking...

forum.ih8mud.com

 

[Dan Lee]

Thank you. Just making sure the shop, me and you guys are all talking about the same thing. I got confused for a min. Seemed like the shop was surprised that the heat exchanger cover was the culprit.

 

[linuxgod]

Thank you. Just making sure the shop, me and you guys are all talking about the same thing. I got confused for a min. Seemed like the shop was surprised that the heat exchanger cover was the culprit.

It's not the only place coolant can leak from, but it is a somewhat common one.

 

[Toyomub]

Hi - I'm mechanically challenged. This valley leak that seems prominent, from where is the coolant leaking into the valley? I've seen mention of manifolds and heat exchangers. Are both of these possibilities leading to coolant in the valley? Or is the leak really from the heat exchanger and the manifolds need to be removed in order to fix the leak?

Please help me understand (somewhat urgent) what part of the engine is really leaking and what needs to be fixed.

Thanks!

If the leak is in the valley, it's likely coming from either the intake manifold or a heat exchanger. Both could cause coolant to pool there. To pinpoint the source, a thorough inspection is needed. If it's the heat exchanger, you might need to remove the manifolds for access.

 

[Dan Lee]

Thanks, good to know. My mistake - I thought the valley leak was primarily because of leak through the heat exchanger. Inspection eliminated the manifolds and pointed to the heat exchanger. I guess that's what I was expecting although seemed a bit surprising to the shop. No biggie, just making sure this is all the same thing.

Not original owner so not sure if I should consider replacing the knock sensors or anything else in the valley. They may have been already replaced at the 90K service (or whatever) before I owned it.

 

[bloc]

Specifically the intake manifold can’t be the source of coolant, though the throttle body on the front of it does have a coolant loop, I’ve never heard of one leaking.

 

[Dan Lee]

Dumb question 2: after using fixing with the 1282b sealant, should I let the truck sit for awhile (few days?) to let it cure? I drove it home but other than that, not sure if it's okay to drive immediately or if i should let the sealant cure for period. Is there a recommendation? It's not a daily driver.

 

[nwfl4runner]

Dumb question 2: after using fixing with the 1282b sealant, should I let the truck sit for awhile (few days?) to let it cure? I drove it home but other than that, not sure if it's okay to drive immediately or if i should let the sealant cure for period. Is there a recommendation? It's not a daily driver.

I believe FSM says 2 hours before driving

 

[Dan Lee]

Thanks. Okay, so should be good to drive from now. Not a daily driver but I'll put some miles on it and check for signs of leakage or other issues. Make sure it's ready for summer trips.