Coolant leak from what appears to be center rear of motor.

[Acrad]

@2001LC What intervals(s) were coolant changed at? Lots of opinions and rumors over the years as to cause on many Lexus/Toyota products with these issues. I’ve seen everything from bad FIPG by a robot, coolant acidity, to a greasy chip eater on the assembly line.

These are well regarded SAIP bypass kits

Search By Vehicle: Product Results | Hewitt Technologies

Find compatible Secondary Air Injection Bypass Kits and Kit Addons for your Toyota or Lexus Truck and SUV.

hewitt-tech.com

 

[bloc]

@2001LC What intervals(s) were coolant changed at? Lots of opinions and rumors over the years as to cause on many Lexus/Toyota products with these issues. I’ve seen everything from bad FIPG by a robot, coolant acidity, to a greasy chip eater on the assembly line.

These are well regarded SAIP bypass kits

Search By Vehicle: Product Results | Hewitt Technologies

Find compatible Secondary Air Injection Bypass Kits and Kit Addons for your Toyota or Lexus Truck and SUV.

hewitt-tech.com

I’m just a guy writing on the internet but the pictures posted in the last page tell the story. RTV should not vary from being that thin near the bolts to that thick between them. Period. As the cover and block expand/contract the RTV has no choice but to eventually fail due to the material shearing at different rates.

I actually wonder whether marginally less torque could help prevent future failure. A better RTV likely would. Stiffening the cover somehow.. ultimate fix, but also impractical.

I do know if I ever dig into this I’ll be cleaning the threads, using new bolts, and a calibrated in-lbf torque wrench to put the specified value closer to the middle of its range. IMO bolt torque and ultimately the correct clamping force (meaning not too much) is critical to this all working.

 

[Acrad]

Great feedback!!! Thanks!!

 

[2001LC]

@2001LC What intervals(s) were coolant changed at? Lots of opinions and rumors over the years as to cause on many Lexus/Toyota products with these issues. I’ve seen everything from bad FIPG by a robot, coolant acidity, to a greasy chip eater on the assembly line.

These are well regarded SAIP bypass kits

Search By Vehicle: Product Results | Hewitt Technologies

Find compatible Secondary Air Injection Bypass Kits and Kit Addons for your Toyota or Lexus Truck and SUV.

hewitt-tech.com

This one had extra coolant flushes and refreshes. Radiator cap and thermostat replaced at 88K. No sign of every running hot. One coolant refresh before 88K (1st owner) with water pump at 65K. We did flush at 88K and 10 years as a PM. It than had timing chain cover oil leak repair, so would have been another refresh ~95K. I just did another full flush at 121K miles.

I've heard/read the talk of grease chick eating fingers of assemble workers, bad robot, bad day FIPG. All are possible. But I'm just going I what I saw and my experiences with other engine.

I’m just a guy writing on the internet but the pictures posted in the last page tell the story. RTV should not vary from being that thin near the bolts to that thick between them. Period. As the cover and block expand/contract the RTV has no choice but to eventually fail due to the material shearing at different rates.

I actually wonder whether marginally less torque could help prevent future failure. A better RTV likely would. Stiffening the cover somehow.. ultimate fix, but also impractical.

I do know if I ever dig into this I’ll be cleaning the threads, using new bolts, and a calibrated in-lbf torque wrench to put the specified value closer to the middle of its range. IMO bolt torque and ultimately the correct clamping force (meaning not too much) is critical to this all working.

I'll add a little more.

Toyota FIPG is known as same of the best there is. I just don't see leaks from it. But my specialty is the 4.7L of the 100 series. We don't see factory FIPG leaks or proper shop applied fFIPG, leaks.

The valley coolant heat lid is only place I saw coolant was getting between it and FIPG. FIPG was remaining on block too, and without signs of coolant getting under it. There was also a large ring of FIPG, hanging from lid as I removed it. This would have been excess FIPG that squished inward when assembled. There was also some FIPG visible on out side seam, pre-disassemble. So it had more FIPG applied than needed. Uneven torquing down in stages, form factory although possible not likely. It appeared to me as if the lid expanded between bolts.


Interesting though on torque @bloc . But 4.7 has some lower, high and mixed:
We don't see this in water inlet to water pump FIPG joint of the 4.7L. Which is torqued to 13ft-lbf. But it is very stiff & thick aluminium and only about 6" total surface. I've seen those at 250K miles and 20 plus years old, without any leak from factory seal FIPG joint. I compared these 5.7L valley water heat lid in size, to oil pans in the 4,7L. 4.7L oil pan #1 is aluminium. They have ~16 bolts & nuts with much less distance between them. With a torque spec of only 66IN-lbf (~5ft-lbf) on their 10mm bolts, but 31 ft-lbf on their 12mm. Those are factory FIPG oil sealed. Second oil pan is steel, FIPG oil seal, with same bolt spread and all 66In-lbf torque. I've seem oil pan of 20 plus year old 500K miles 4.7L, but never seen a leak. Seen the 4.7L over-heat to point engine and all rubber hose change color, head warp and plastic intake manifold melt. Still no leaks at factory FIPG water inlet or oil pans. Even the 1 million mile 4.7L USA built Toyota, didn't "report" any leaks. The 98-02 Transmission is also FIPG seal, with same close bolt spread & light torque of 4.7L oil pans. Yet never see them leak.

We'll never know for sure why. But I can say I cleaned, applied FIPG and torqued in stages and cross start pattern to spec, doing the very best job I could. I have concerns! where I normally do not.

 

[JZelnick]

Finally scheduled this repair at 200k. I knew it was leaking for the last 10k and topped off the coolant at each oil change. My mechanic said this is the worst one he’s done. There are signs of mice, which was surprising as this is my daily driver. Knock sensors, harness and air pump valves will be replaced.

 

[2001LC]

So I just did another valley Heat Exchange cover re-seal! Which came in with a cracked radiator badge.

I've a new bore-scope with 360 joy stick gullible snake camera. So I'm now able to easily get under intake manifold and peak at Heat exchange, even with foam in place.

Just like last months months in a 08 w/121K. This, a 2014 w/125K main leak point, is at front bolt on RH side.

So I just did another valley Heat Exchange cover re-seal

This 2014 w/125K leak, did seems to be in a later stage of leak. In that it appeared to weep nearly 360 degrees around perimeter of cover.

It, came in with a cracked radiator badge.

I wash/rinse radiator fins before removing, even when replacing. This is a first step in getting the other radiators (condenser & A/T fluid) clean.

After washing radiator of fins, while in vehicle. As you can see, its fins are still in need of more rinsing/washing. They always are.

In the shop I use HP air and shop vacuum, to further clean AC condenser.

Radiator fins need cleaning! Alert Alert Alert

I've a 06LC w/192K I just bought. In reading history I found PO complained of engine temp raising when both front and rear AC on. Toyota Dealership diagnosed with clogged radiator fins. Recommended new OEM radiator, $600 for the US spec Radaitor plus coolant and labor. They should have added...

forum.ih8mud.com

 

[2001LC]

I found interesting, that thes factory changed FIPG from the black (2008) to gray (2014)

2014

2008

 

[amunsey]

Well I believe my LX has this dreaded valley plate leak now. Im just shy of 165k miles on my '11.

I don't feel too comfortable handling this repair myself so I may end up having a shop do it. I got quotes from both the Lexus and Toyota dealer and they both were in the ~$1900 range. I called my local indy shop but they didn't want to touch it. I'll try to get some additional quotes before making a final decision.

I'm of the mindset that while you are in a certain area of the vehicle (especially an area that requires a bit of labor to get to), you should replace any items that may go bad so you don't have to access the area again for awhile. Based off of the posts I have been reading on here, it sounds like the following would be the possible considerations:

• Secondary Air Injection System Valves/Cleaning
• Serpentine Belt
• PCV Valve

However, I don't want to repair or replace items that have been working fine, and then end up creating issues. Assuming that my engine is currently not experiencing any issues with the items listed above, would any of these items still be good to address while the shop is handling the valley plate (radiator and water pump were already replaced)?

 

[2001LC]

Well I believe my LX has this dreaded valley plate leak now. Im just shy of 165k miles on my '11.

I don't feel too comfortable handling this repair myself so I may end up having a shop do it. I got quotes from both the Lexus and Toyota dealer and they both were in the ~$1900 range. I called my local indy shop but they didn't want to touch it. I'll try to get some additional quotes before making a final decision.

I'm of the mindset that while you are in a certain area of the vehicle (especially an area that requires a bit of labor to get to), you should replace any items that may go bad so you don't have to access the area again for awhile. Based off of the posts I have been reading on here, it sounds like the following would be the possible considerations:

• Secondary Air Injection System Valves/Cleaning
• Serpentine Belt
• PCV Valve

However, I don't want to repair or replace items that have been working fine, and then end up creating issues. Assuming that my engine is currently not experiencing any issues with the items listed above, would any of these items still be good to address while the shop is handling the valley plate (radiator and water pump were already replaced)?

Replace Serp belt anytime it is worn or squeals. It's not really a while in there, during valley heat shield reseal. Which Valley heat shield is, a top of engine service

A very good while your in there:
What I found to be a very good "while in there" during heat shield reseal. Is both the front and rear rubber grommets for the PCV separator. These rubber grommets shrink and harden with time. Doing these during HS reseal, is a small thing. But overlooked in general PM.

Must while resealing valley coolant heat shield:
Clean all three radiators (A/T oil cooler, AC condenser, engine) fins. Even if replacing Radiator, get other radiator fins cleaned out. Bugs, grasses dust, mud, bird feather, styrofoam and all manner of road debris clog radiator fins. This is leading cause of running hot and boiling fuel. Running hot increase likelihood of heat shield leak, sooner rather than later.

If thermostat and or radiator cap are aged. Replace them, while doing the reseal of valley coolant heat shield. While R&R thermostat, Serp belt is kind of a, while your in there. Which are both front of engine services.

All gasket, seals and O-ring touched during the service. Have them replaced.

Not really a while your in there, but a very big deal:
S.A.I SW BK1 & BK2, aren't something a shop is going to clean. Nor should they need too. They replace S.A.I. SW's if they fail. Key for these is to keep clean, by having a good filter in the pumps (blowers in RH fender well). Unfortunately these non replaceable filters are failing. This I strongly feel we need to start adding a replaceable filter to the two pumps, of the 5.7L in 200 series.

I do a mod on the 4.7L in 100 series. Where I add an easily replaceable filter, to the S.A.I pump, removing it's internal filter (if even there any longer). I'm finding the internal filter are gone in 5 out of 10. Loss of this filtration. Will not only result in SW's and other S.A.I components getting dirty and fouling them. It will damage the engine and CATs. All S.A.I system internal filter will fail IMHO!

S.A.I. Filter Modification, in VVT engines. To prevent its failure! Alert Alert!

We've a $2.00 part in the S.A.I. (secondary air injection) system of the VVT engine, that is taking-out ~$7,000.00 $15,000 $25,000 (inflation) in parts. WOW! I've a very easy and cheap WORK AROUND. You are going to love this ;) This thread is dedicated to the 4.7L 2UZ-fe VVT engine, in the...

forum.ih8mud.com

 

[amunsey]

@2001LC Awesome, I appreciate all that info!

 

[Acrad]

Some of the SAIP failures on 1UR-FE in 460 are result of moisture and not the foam debris from the air pump.

https://lexusgxor.com/_media/general:special_service_campaign_jlg.pdf

10-13 are basically covered by an open-ended campaign otherwise Lexus would have to reprogram the logic in that system which doesn't run at shutdown like '14+

Alternative is -->

Hewitt-Tech Gen 2: Secondary Air Injection System Bypass Kit (Plug & Play)

Gen 2 (Plug & Play) SAIS Bypass Kit is compatible with most Toyota / Lexus Trucks & SUVs. It enables you to clear the Check Engine Light, Limp Mode and error codes related to both mechanical and electrical SAIS faults. P0412 P0415 P0418 P0419 P1441 P1442 P1444 P1445 P2440 P2441 P2442 P2443 P2445...

hewitt-tech.com

 

[2001LC]

The GX TSB, in mentioning moisture. Is saying; moisture may possibly be cause of filters failure:

Toyota TSB states "There is a possibility that moisture in the air may cause a filter in the vehicle emissions system to degrade. This degradation could cause damage to other parts of the vehicle emission system and illuminate the check engine light (Malfunction Indicator Light)."

Toyota in many TSB,do not tell the whole story. Why not give full disclosure! It opens then up to more recalls.

Fact is this little filter, once missing. Can damage much more than the S.A.I system. In the 100 series it can cause upwards of $15k damage. In the 200 series can be even more.

IMHO they'll all fail time. It is a design flaw, they're now (GX recall) aware of.

I've learned over the years, since I first found the number 1 cause of S.A.I. system issues (DTC) & both CAT's failing on the 4.7L 2UZ-fe VVT. The debris from foam filter and contaminates it holds. Is only the start of the down stream contamination/damage.

IMHO we've 2 choices, for street legal:

• Replace SAI pumps, every "so many" years. Which houses the foam filter.
• Install an easily replaceable external filter. Issue solved.

Alternatively:
Hewitt block-off or disable kit!
I personally do not install or service, Hewitt block-off or disable kit on any street legal 100 or 200 series. My carbon footprint is bad enough, without removing or disabling any pollution devices.

Additionally: When doing a PPI for a potential buyer, and I see a Hewitt kit installed. I recommend the addition of a compression test, to the PPI. Since so many of these kits' are install post issue with S.A.I. system. All to-date have failed!

Last paragraph in the Hewitt-tech web page:

DISCLAIMER:

It is illegal to remove, dismantle or otherwise cause to be inoperative any pollution control device required by federal, state, or local emissions law. Our bypass kits are sold for off-road, competition or other emissions exempt vehicles only. No other applications are intended or implied. By installing or using this SAIS Bypass Kit the vehicle owner and installer acknowledge and assumes ALL risks associated with its use.

 

[Acrad]

There are many moisture related air valve failures reported on the 460 where the foam was intact and the valves simply start sticking open or close. You see far less failures on the '14+ 460s since they run a shutdown routine. The 10-13 models only run at startup.

I installed the UNI filter years back but in no way feel this entirely resolves the concern on my 460.

@hewitttech - Anything to add to discussion since your product is discussed in this thread?

 

[2001LC]

We've really gone off thread topic. Perhaps save for anther time & thread!

 

[GOLIGHTLY]

Maybe a question best directed to someone like @2001LC or anyone else seeing a lot of these trucks... I've scoured on here and haven't seen any discussion of failure of the 1282b FIPG on any rigs that have had that reseal performed. Maybe too soon given that they're running into this around 120K-ish miles, but just curious if you've had any come back in after using that "new" FIPG? About to take care of this myself and just making sure the community guidance is still the 1282b FPIG.

 

[Toyo8696]

Maybe a question best directed to someone like @2001LC or anyone else seeing a lot of these trucks... I've scoured on here and haven't seen any discussion of failure of the 1282b FIPG on any rigs that have had that reseal performed. Maybe too soon given that they're running into this around 120K-ish miles, but just curious if you've had any come back in after using that "new" FIPG? About to take care of this myself and just making sure the community guidance is still the 1282b FPIG.

I have done about 10 of these repairs and haven’t had any issues with them leaking again. The majority of them I have done have been on 2014 to early 15 model Tundras and LC’s.

 

[GOLIGHTLY]

I have done about 10 of these repairs and haven’t had any issues with them leaking again. The majority of them I have done have been on 2014 to early 15 model Tundras and LC’s.

Awesome, thanks man. Just caught that the 1207 is way cheaper but tbh $80 isn't breaking the bank for me as long as its the best FPIG for the repair. Thanks for the intel

 

[GOLIGHTLY]

I've done this repair and run into something odd.. I know that one of the O-rings on the front end water pipe didn't seat correctly, that made itself apparent as soon as I got moving. But that was associated with jump in coolant temp/attempted overheating before I shut the truck down. No symptoms at idle, only once moving. My understanding is that coolant would still be moving through the system, and that O-ring should have presented itself solo, not alongside overheating. My question is: does the FSM have a process in place or a mention of brief overheating being normal as the system cycles new fluid into the heat exchanger? Once the truck cooled down, no additional coolant was pulled from the overflow reservoir either.

EDIT: Open comment to Toyota -- air valves... thats all.

 

[2001LC]

Coolant flows throughout entry system once operating temp reached. The higher the RPMs, the fast the water pump turns the faster the flow.

I found the first heat exchange reseal, I did. The forward O-ring (pump side) developed a leak, about 3 months later.

I replaced the water tube with new OEM, after finding old out of round. The new was also out of round but less so, and slightly larger OD. I found it interesting. A $90K vehicle and water pipe connecting heat exchanger to water pump. Was not a precision manufactured part.

 

[GOLIGHTLY]

Coolant flows throughout entry system once operating temp reached. The higher the RPMs, the fast the water pump turns the faster the flow.

I found the first heat exchange reseal, I did. The forward O-ring (pump side) developed a leak, about 3 months later.

I replaced the water tube with new OEM, after finding old out of round. The new was also out of round but less so, and slightly larger OD. I found it interesting. A $90K vehicle and water pipe connecting heat exchanger to water pump. Was not a precision manufactured part.

That’s good to know actually, might be worth stashing a spare somewhere.

Wound up finding my system hadn’t fully burped itself. I guess a 20 minute idle and burp wasn’t sufficient. Good excuse to do a full coolant exchange.