Leaking valley plate / heat exchanger

I've been smelling coolant lately. Faintly, but persistently. I didn't see any sign of leakage, and the level in the reservoir was still pretty good. But just now I drove her up on the ramps to do an oil change and saw this.

Hovering over the hot engine, I can't see where the heck it's coming from. But judging from how it has been trickling down the bell housing, it's somewhere at the rear of the engine, slightly toward the driver's side.

Anyone dealt with this already?

 

Intake valley leak possibly

 

I had to google what that was. I'm still pretty vague on it. LOL But there would be coolant on top of the engine, right? I'm not able to find any.

Try as I might, I'm also unable to get an iPhone up in there. Or down in there, from under the hood. I need a tight-spaces-around-corners-looky-thing.

 

Under the intake maybe?

 

My water pump started leaking at 46k with 28 days left on the 5 year warranty.

My (private shop) showed me the truck, looked like yours. Said the coolant was probably being blown around from high speed commute and such.

Obviously each situation is different, but it could be a simple fix.

I would suggest cleaning it all up and seeing if you can trace an origin point.

 

It's remarkably less messy than it looks. It's a very clear trail. And not much quantity, the reservoir is still half full or more. I just need a scope of some kind to see where the heck it's coming from.

I had the water pump replaced about 20K miles ago.

 

I gave it another look today using one of those mirror-on-a-stick things. I still can't trace the coolant trail upstream of the bell housing. I can't see any trace of fluid around the intake manifold. Or anywhere else other than the tranny. This tantalizing glimpse was the best I got.

I ordered an endoscope today, which should arrive tomorrow. I may not be able (or willing) to fix the problem myself, but I don't wanna take it anywhere without knowing what's up.

 

A few more pics from today with the new $30 endoscope. The best I can tell, it SEEMS like the leak is just rearward of the lower end of that shiny tube, where the red arrow points. It seems to trickle down and puddle in one spot, and also run down the side of the bellhousing. It's been a very slow leak but I think it's speeding up.

 

Here was a thread I posted awhile back on the possible problem. I recall coolant on the bell housing and could see it coming from further up on the engine. Hopefully this provides someone more knowledgeable than I enough information to determine whether you might have the same issue.

https://www.tundras.com/threads/fip...nt-leak-at-heat-exchanger.98892/#post-2518489

 

Yup, looks like that's definitely what's up. Why couldn't it have been a hose clamp? LOL

Looks like a PITA (or in the wallet).

 

Well hope it ends up being a hose clamp or something else that's less of an issue. Thankfully, my issue was under warranty. Since you have a 2016, guessing you're not as fortunate. Really sucks. To me, it's a design or manufacturing issue to have someone essentially create a gasket with a little tube of FIPG. So if the person doesn't use enough FIPG in the right places, you get a leak. And not a cheap leak to fix. Some leaks will show early, some later. The lucky folks see the leak during warranty period. Why not have a gasket and take the human element out of it? Sorry, I know this doesn't help your situation. Still pisses me off though. I expect better from Toyota. Wish I had a better answer for you.

 

Meh, it's the first problem I've had in a quarter million miles. I'm okay with it.

I think it's definitely the valley plate though. I gotta get on the phone tomorrow and see what it's gonna cost me.

Couple more pics from this morning. These I got from above the engine, reaching behind the intake manifold, with the endoscope doing a U turn and facing forward under the manifold. I got the closeup one first, then backed away to try and give some perspective. This endoscope has a learning curve of its own.

 

I'll be curious to hear the resolution cost. My recollection of specifics is a bit vague, but I believe my issue required somewhere around 25 hours of shop time plus parts. Since it was under warranty, I didn't see a total cost. Hope the valley plate is a bit less involved.

 

I'm not sure what's involved in resealing the valley cover, but i had the intake removed and reinstalled on my 5.7 in an afternoon when i was doing the air pump block off kit. 25 hours sounds way too high.

 

Yeah that sounds more like cam towers.

 

My recollection of specifics, including shop hours, on fixing my heat exchanger sealant issue is a bit shaky as it was awhile ago and still under warranty. But I recall seeing the engine in a dismantled state and was surprised at the extent the tear down. Sounds/looked a lot more involved than cam tower fix described above. But hope I don't have to deal with cam tower either.

 

No, thank goodness, the cam tower is a MUCH worse job. I was recently quoted $5K at two different stealerships to do a cam tower repair.

I just now got a quote of "$1500-$1900" for the valley plate job from the stealership, and "about $1500" from an independent guy.

 

This might be one I’d let the dealership do. Sure a mechanic has done this several times. Not a bad price to me. Once done it will be good forever

 

Dealing w this currently too and original quote was $2200 from dealership. I bought extended warranty so had them do. Part of repair was denied so I’m still working it w tfs warranty and the dealership. I’ll update my other post once I get it resolved.

 

It's a pain in the arse, but doable in about half a day, actually really helped me understand the engine setup allot better! FYI, REPLACE THE O-RINGS on the water pump pipe!!!! and LUBE THEM UP! i had to do the entire process again because of a 5.99$ o-ring i didn't replace with a new one!

https://www.tundras.com/threads/tundra-had-a-minor-heart-surgery-today.126254/

 

So you did it yourself? Is the inlet pipe right there? Warranty didn’t cover the pipe so dealer charged me $800. After more calls arguing w warranty I finally understood it was just the part not covered but labor would be. Said labor wasn’t submitted by dealer. I’m trying to see why they charged me 800 when the fipg was covered. Warranty guy said that doesn’t seem right either. Trying to get ahold of service manager.
Anyways, helpful to know what extra work is involved w replacing inlet pipe or o rings on it.

 

R

They replaced the entire pipe? In round 2 of my DIY, i replaced just the O-ring's that are on either end of the inlet pipe, the 'inlet pipe' is literally just a metal tube coming out of the water-pump feeding coolant to the engine, the pipe is NOT a part meant for replacement, the O-RING's on the tube are intended to be replaced. Sounds like typical Stealership antics of making more $$$ off of people...

 

Looking that way. Part was just over $20 so not worried about that but over $700 in ADDED labor? Your perspective on where the inlet pipe is relative to where they resealed will help me keep pushing

 

To remove that "inlet pipe" and replace those o-rings is ALLOT of labor, the 'valley plate' is where that 'inlet pipe' from the water pump plugs into the 'valley plate' and distributes coolant into the top of the engine. it took me ~6 hours for R&R of everything, each time . So it's not a lite job, but it's not terribly complicated either. It sounds like your 'warranty' covers just the parts maybe?

 

I'm trying to sort out the various posts to better understand the issue(s). Mostly curiosity as it's doubtful I would ever dig into this type of problem. But curious and would like to better understand nonetheless. Are there multiple failures that cause coolant to leak on the bell housing and back of engine? Sounds like a leak can occur either at the inlet pipe, valley plate, or possibly heat exchanger as well. Or is the valley plate issue the same as the FIPG heat exchanger issue I described? I don't recall any mention of the valley plate being discussed when my rig was in the shop, but at the time my brain was getting overloaded with info.

 

Okay now hold on! Half a day??

In that link, you said "two days so far" while the engine was still torn to pieces and the plate was still off!

 

Maybe the second round was a half day , i don't mean from sunrise to sunset or anything, i'm not a masochist!

 

The plate is the "heat exchanger". However, the real heat exchanger is actually the coolant that is circulated in the cavity between the plate and the engine block. There is basically a cave formed by the valley plate over the top of the block that is filled with coolant in circulation to maintain a safe operating temperature.

 

Clarifying my question. The FIPG on valley plate was covered. I got charged $800 to do the inlet pipe as incremental labor to do that on top of everything to do the FIPG. I can’t tell from diagrams. Seems like once they get to the plate the pipe is right there and shouldn’t warrant an additional $800 labor. Am I way off from your experience?

 

Incase anyone needs a pic of the intake manifold off. The two prongs in the valley are coolant lines. If I remember correctly.