Valley Plate Coolant Leaking

[jmanscotch]

There’s always those things that effect early models predominantly, so it’ll be interesting to see if this is one of those or if it begins to span the years as the newer models age.

Honestly though, a cooling system refresh, the valley pan and a few little other repair items at 100k mile intervals is still not bad IMO.

I had the transmission out twice before 80K miles in my last JK Wrangler, engine burning a quart every 1,000 miles before 100K too. My BMW 135i got a clutch at 28K miles (due to pressure plate bolts backing out not wear), rebuilt turbos at 35K and intake valves underwent a walnut blasting (for carbon buildup) at 40K. Hell, even my Tacoma had me rebuilding the driveshaft, replacing a front diff bearing, lower control arms and HVAC blower motor at 100k miles.

 

[MT Economist]

Good work and thanks for sharing.

 

[Tex68w]

I'd rather have those Tacoma issues than anything cooling or engine related haha. Jeep and BMW's are amongst the worst so I am not surprised. I agree that I hope this is relegated to the earlier models in time.

 

[carlos33018]

It's a shame that this is becoming a more prevalent issue with these trucks. I am already at 35K miles on my 2019, at this rate odds are this issue will rear it's ugly little head in another three or so years. Hopefully this ends up being a early 460 issue as I have yet to hear of any on the later year model trucks, yet lol.

This is happening to A LOT of the V8's in the Lexus / Toyota lineup. This issue is very common on the IS-F / Tundras (Same 4.6L) and LX570. Supposedly, this is happening due to contamination when the sealer was first applied, which SHOULD mean that there should be a process improvement with the later model years. However looking at how this sealer is ALWAYS in contact with coolant, and the high level of humidity under that plate, that its only a matter of time before it fails.

I am expecting to keep the truck for the long haul, unless a catastrophic thing happen which is basically engine or trans failure. These sorts of little things will show up and will have to be taken care of, especially for those of us with a high millage GX. The good thing is that a lot of this can be done with a little time and patience, and then you can use the $$ you saved to reward yourself with something REALLY nice .

 

[jmanscotch]

This is happening to A LOT of the V8's in the Lexus / Toyota lineup. This issue is very common on the IS-F / Tundras (Same 4.6L) and LX570. Supposedly, this is happening due to contamination when the sealer was first applied, which SHOULD mean that there should be a process improvement with the later model years. However looking at how this sealer is ALWAYS in contact with coolant, and the high level of humidity under that plate, that its only a matter of time before it fails.

I am expecting to keep the truck for the long haul, unless a catastrophic thing happen which is basically engine or trans failure. These sorts of little things will show up and will have to be taken care of, especially for those of us with a high millage GX. The good thing is that a lot of this can be done with a little time and patience, and then you can use the $$ you saved to reward yourself with something REALLY nice .

Curious your take on using the standard FIPG versus that $50 a tube stuff some are suggesting. If you have to do the repair on yours, which are you going with?

I went for the standard $14 a tube stuff. While I saw many argue for the other stuff, the reality seemed that no one was using it and dealership receipts and even techs (on the IS-F forums) noted almost everyone just using the basic stuff.

My original sealer was grey from factory.

Where the FIPG I replaced it with was black, not sure any significance.

 

[Tex68w]

Even as small of a issue as some may view this, it shouldn't be happening this soon IMHO.

 

[jmanscotch]

Agreed, but really the options are to be upset or deal with it knowing you’re still better off in a higher mileage Toyota/Lexus product than most any of the competition.

 

[Acrad]

An article on the leak.

GX460 coolant leak – a hidden leak from deep in the engine

GX460 coolant leak - a hidden leak from deep in the engine and repairing the valley plate coolant leak

carspecmn.com

 

[jmanscotch]

NEVERMIND, FIGURED OUT MY ISSUE.

Working on the DIY and am running into the issue where my photos orient themselves as they wish. Example: this one must have been taken with my phone sideways, but even rotating it on my iPhone before emailing it and rotating it once it's on my PC seem to have no effect on the fact that it get's uploaded as an attachment here and is sideways.

 

[maingear]

Did you lube the orings on the pipe with something like dc4 grease?

You say it will roll and kink when they are dry hole'd?
Excellent info!

 

[jmanscotch]

Did you lube the orings on the pipe with something like dc4 grease?

You say it will roll and kink when they are dry hole'd?
Excellent info!

I didn’t lube them with anything other than coolant, probably a good option to, I simply had coolant or a few likely inappropriate lubricant options in the garage, so I stuck to coolant.

Unfortunately, I did try take care to ensure they didn’t go in dry hole’d. I coated the o-rings right up until they went on and even used a coolant wetted finger to run some coolant into the necks where the pipe would be. So O-ring and the surface it slid on we’re all wet with coolant.

I’m guessing my main cause of the kink was two things; a thin layer of coolant wasn’t the worlds best lubricant and the way I connected the pipe to the valley plate first, before stabbing it into the block neck, meant I fought with some weird angles and tweaked the tube a good bit making it all line up. Naturally, some of the jerkiness of install was due to being nervous about getting it perfect in one go.

The second time, I placed the tube into the block first, then joined the valley plate to it and turned the tube a bit to make sure the o-rings settled into their groves before resting the valley plate down where it needs to go.

 

[r2m]

Is it good to go now?

 

[jmanscotch]

Is it good to go now?

Why ya gotta ask questions like that, Richard? lol

The valley pan seal seems to be fine now, yes.

Current issues:

- water pump bearing and squealing belt still an issue
- noticed a coolant leak that was smoking on the headers on my way home yesterday and found I had wallered up the hard heater line that runs along the firewall just below the cowl and the end connection to the rubber hose wasn’t sealing well. Fixed that by running some needle nose pliers into the end of the pipe rotating it around until the pipe was round again. Is wallered out just a Texas phrase? My wife had quite a laugh at me saying the pipe end was wallered out.

- It struggle to start this morning in 6 degree cold, no codes thrown but my scanner says it failed an evap system leak test, so that secondary air pump tube I broke and just taped up isn’t liking its temporary repair and is giving me some air/fuel or sensor related issues to starting when cold.

MyLParts said the waterpump has the standard genuine Lexus parts warranty, only catch is I have to have a dealership give verification that it’s bad. Kinda a crap plan as the waterpump was $125 and diagnosis from the dealership is $100, so you’re effectively buying the pump again anyway. I’m dropping it off at the dealer today to confirm, then I’ll probably just have them do the replacement and try to talk them into throwing in the replacement pump for free. Quote was $974 for water pump replacement, figure another $50 for belt. I’ll replace the air hose myself (though they charged me $85 for the part that shows a list price of $50 online).

 

[re_guderian]

I think it's my turn wasn't like this a few weeks ago when I was doing a brake bleed. Changed the oil this morning and saw this... Gonna have the shop do this one due to time constraints, road trip to Texas in 5 days. Anything else to do while they're in there? 167k on truck. no history of water pump replacement at Lexus. Do it?

 

[jmanscotch]

Bummer man, that definitely looks like the valley pan leak.

Only maintenance items that can be done, with no extra labor charge, are PCV Valve replacement and Coolant drain/fill.

The water pump and such doesn’t come off for the repair, but the coolant system is open/drained, so it might save you a few bucks overall on coolant costs if you want to tackle it at the same time.

 

[Tacticus]

Thank you so very much for posting everything I am about to look into this issue myself. My coolant reservoir keeps getting below low. I have a 2015 with 110k. I'll look tomorrow under, currently off roading and going to go to the store to grab some coolant and fill up the reservoir to the max line again and see what happens. Bay is hot not sure if that is normal and temp gage on dash is always in the middle, where does everyone else's line up? Also any good pointers to look for leaks at, I'm just going to search with what I can see.

 

[jmanscotch]

Thank you so very much for posting everything I am about to look into this issue myself. My coolant reservoir keeps getting below low. I have a 2015 with 110k. I'll look tomorrow under, currently off roading and going to go to the store to grab some coolant and fill up the reservoir to the max line again and see what happens. Bay is hot not sure if that is normal and temp gage on dash is always in the middle, where does everyone else's line up? Also any good pointers to look for leaks at, I'm just going to search with what I can see.

Unless it’s dangerously low, the leak shouldn’t cause any actual cooling system performance issues (like overheating). Mine surely didn’t either, just kept getting low on coolant and if would smell hot coolant when off roading (and the engine was properly hot) and when I’d go up an incline off road.

If the leak is bad enough, coolant will accumulate and eventually run down the back of the engine and down the transmission bell housing. Look there first (from underneath, with a flashlight if needed) and look for a pink cotton candy like residue. If it’s not that bad yet, you might have to look harder at the back of the engine from the top side or between the intake runners (trying to peer down under the intake manifold).

 

[Tacticus]

Unless it’s dangerously low, the leak shouldn’t cause any actual cooling system performance issues (like overheating). Mine surely didn’t either, just kept getting low on coolant and if would smell hot coolant when off roading (and the engine was properly hot) and when I’d go up an incline off road.

If the leak is bad enough, coolant will accumulate and eventually run down the back of the engine and down the transmission bell housing. Look there first (from underneath, with a flashlight if needed) and look for a pink cotton candy like residue. If it’s not that bad yet, you might have to look harder at the back of the engine from the top side or between the intake runners (trying to peer down under the intake manifold).

You are the absolute man I so much appreciate your help responding here especially so quickly while I am out here wheeling. I will let you know tomorrow after I look. Seriously appreciate your help and tips.

 

[Tacticus]

I didn't see an

You are the absolute man I so much appreciate your help responding here especially so quickly while I am out here wheeling. I will let you know tomorrow after I look. Seriously appreciate your help and tips.

Trying sticking out that caught my eye I'm going to look further when I get home. Thanks again for the help, I ended up stopping at the store and filling the res up to max, we will see how long till it goes empty again

 

[Tacticus]

So far this is how what I am dealing with after the fact.

I can't find any leaks but this is what I am dealing with

Saturday: res is full then wheeled for 2hrs
Sunday: drove 1.5hrs highway
Monday: 3/4 full, drove 30mins that day
Wednesday: 1/2 full -drove another 1hr combined