Mice tend to chew on the knock sensor harness wires for some reason. Ask me how I know. Not you will necessarily need one, but don’t be shocked if yours has been compromised when taking things apart
Kind of "Mystery" Coolant leak back of engine (heat exchanger valley leak) (3 Viewers)
- Thread starter cc93cruiser
- Start date
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Are there any detailed videos of doing this on the 200 series? It seems like most are from the isf, GX, Tundra, etc.
It’s very straightforward. Just time consuming.
Wah00
SILVER Star
I'm about to pull the trigger on a 2019 200 for Mrs. Wah00.
She's been driving a 2012 Sequoia, and we dealt with the valley leak problem with it.
I've searched the forum and can't seem to find if this issue was resolved at any point by Toyota, or if the newer 5.7s (including the 2019 ...) will also be subject to the need for this repair. Any help appreciated.
She's been driving a 2012 Sequoia, and we dealt with the valley leak problem with it.
I've searched the forum and can't seem to find if this issue was resolved at any point by Toyota, or if the newer 5.7s (including the 2019 ...) will also be subject to the need for this repair. Any help appreciated.
gray rider
SILVER Star
easy repair...
gray rider
SILVER Star
Les Paul gold top guitar as well!
Thought the valley plate leak was limited to 2014 and below?
IMO.. I don’t think I would rule out any model year without enough time, heat cycles and mileage
bloc
SILVER Star
This
It's not a matter of if, it's when it will happen.
bloc
SILVER Star
I dislike absolutes. The odds of there not being a single 3UR valley plate that went the life of the rest of the engine without leaking must be very low.
Yes, it's common. But some of us are accruing significant mileage without that failure. I'm at 225k without a hint of a leak.
Edit: it's also not like these fail catastrophically, which would help make the case for doing the job as PM. Owners should just monitor coolant level and address it if it comes up.
Yes, it's common. But some of us are accruing significant mileage without that failure. I'm at 225k without a hint of a leak.
Edit: it's also not like these fail catastrophically, which would help make the case for doing the job as PM. Owners should just monitor coolant level and address it if it comes up.
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The bright side is, it's not a vehicle with many other major issues.
Unfortunately, while beginning my prep for Baja in November, I noticed my coolant reservoir level was below the L mark and barely visible at all.
I do not see any coolant leaks on the top side of the engine.
Looking up from below the truck and past the bell housing, the back of my engine is dry all the way up to the plastic intake manifold on both the driver and passenger sides.
What is the appropriate way to confirm or deny my membership in this brotherhood? Fill the reservoir and monitor the rate of loss...?
The discovery was a bit of a bummer since my truck was cruising for hours on Route 66 in 100 degree heat this weekend with the temperature gauge leaning toward the cool side.
Thanks!
I do not see any coolant leaks on the top side of the engine.
Looking up from below the truck and past the bell housing, the back of my engine is dry all the way up to the plastic intake manifold on both the driver and passenger sides.
What is the appropriate way to confirm or deny my membership in this brotherhood? Fill the reservoir and monitor the rate of loss...?
The discovery was a bit of a bummer since my truck was cruising for hours on Route 66 in 100 degree heat this weekend with the temperature gauge leaning toward the cool side.
Thanks!
TLC2013
SILVER Star
Poke around underneath the intake manifold. You’ll need to remove some of the foam. I tore a bit of the foam off to gain access and used a bore scope camera to find the crusty pink coolant residue that had been slowly leaking out and leaving me with an empty reservoir. I caught it early and never saw coolant down the bell housing.
There’s a work truck that a guy brings in and he has owned it since new—a 2011 Tundra 3UR with over 350K miles, and it has never had a valley plate leak.
One head gasket, cam tower reseal and valve cover gaskets, timing chain tensioners, radiator, water pump/stat, alternator, steering rack, inner and outer tire rod ends, lower oil pan, anything that touches the belt, oil filter housing and cooler/block gasket, all the brakes, all the bearings, bushings, control arms/ball joints, both the CV axles, shocks and springs, a bunch of window regulators and door lock actuators, all of the carpet, weather seals, AC evaporator (and preventatively heater core), AC compressor/clutch, AC condenser, charcoal canister, I remember a few key programs, a lot of TPMS sensors, a lot of tires. Transmission and torque converter.
I think the valley plate might the one thing that hasn’t been touched on that Ship of Theseus Tundra.
Now that I think about it, I don’t see too many valley leaks relative to the number of vehicles with this engine that we see on a daily basis.
You can buy a cheap camera on AMZN that allows you to put it into a hole at the front of the engine, where you would replace the PCV valve. There’s an opening there, and you’ll be able to see the leak with that camera.
Wouldn't the valley plate need to be resealed if you pulled the heads to do a head gasket? I would think you'd need to remove the heat exchanger cover as it's called in the FSM to get the head off? It shows as sub steps in the FSM (under 7. REMOVE VALVE LASH ADJUSTER ASSEMBLY) but I know the FSM often calls for a lot more removal than is actually necessary
Word of caution with the above. My leak was at the front USA passenger side of the heat exchanger cover. It would have been difficult to find with an inspection camera from over the top of the PCV valve. I definitely didn't think I had a leak until I got my intake manifold off and could see the pink crusties on that side. Getting the intake manifold off is a pretty easy task if you really want to do a good inspection. FSM calls for replacing the intake manifold gaskets, so that's the only expense if you go that route by the book. I've read about people not replacing and just reseating, I can't comment on which way to do that. I replaced the gaskets.
