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

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If reservoir isn't leaking itself it has to be something from lower heater lines to coolant hose.... until you pull that skid off just a lot of guesses unfortunately

Sorry
 
If reservoir isn't leaking itself it has to be something from lower heater lines to coolant hose.... until you pull that skid off just a lot of guesses unfortunately

Sorry
Thank you I appreciate it and taking the time to talk about this all. Gonna try and take the skid plat off in a little while and report back. Family friend we are visiting has some tools to work with so at least gonna look at it to try and inspect it more.
 
If reservoir isn't leaking itself it has to be something from lower heater lines to coolant hose.... until you pull that skid off just a lot of guesses unfortunately

Sorry
Check this out. Looks like the return hose is leaking. That clamp doesn’t seem great when you press around that hose to the radiator it squirts our a little coolant.

Any recommendations on getting her tight and snug?
If reservoir isn't leaking itself it has to be something from lower heater lines to coolant hose.... until you pull that skid off just a lot of guesses unfortunately

Sorry

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So since I’m so far from home replacing the clamp isn’t much of an option until I get home. Then I can replace the OEM. But unfortunately I think my options are limited since I don’t have much to drain the radiator. What would I be looking at to drain the radiator to replace the clamp?
 
I think that clamp is fine, just needs to be tightened up. Try that, you can use a flathead screwdriver if you don't have any sockets.
 
You should be able to pick up that clamp at any auto parts store. Wonder if previous owner or whoever worked on previously stripped the clamp out over tightening it?
 
So drove 1000 miles for thanksgiving. Next day took LX out to see the small town we were visiting. 20 minute drive. Parked and sat for 15 minutes. Then a small little puddle appeared. Pinkish I think but hard to tell. Might smell of coolant too but hard to tell. Coolant level on dashboard is normal, same with engine temperature.

No coolant left in reservoir. The only auto parts store open is oreilly’s and they only had one bottle of Xerex Asian Red 50/50. Is that fine - previous owner seemed to be using pink/red?

How screwed am I getting home? Can I top off every fill up and just make it home?

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You should be fine to get home with that. Probably add the water, (Distilled) you can buy from Walmart, or auto stores. I woudl be more concerned where the leak is, why is it leaking.

Did the normal radiator craxck on top open up, or did a gasket clamp let go, or does a hose have a slit in it? You might want to check the source of the leak, becasue if it opens up it wont matter how many gallons of Asian pink you have, you still will not be driving.
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I think that clamp is fine, just needs to be tightened up. Try that, you can use a flathead screwdriver if you don't have any sockets.
Yup got some sockets and tightened it real tight for now!
You should be able to pick up that clamp at any auto parts store. Wonder if previous owner or whoever worked on previously stripped the clamp out over tightening it?
I think the clamp came from the previous owner taking the LX to a bad mechanic. The previous owner very much was the type where when I asked why he replaced the water pump, he wasn’t sure why, and had just taken it to a random friend of a friend mechanic.

You should be fine to get home with that. Probably add the water, (Distilled) you can buy from Walmart, or auto stores. I woudl be more concerned where the leak is, why is it leaking.

Did the normal radiator craxck on top open up, or did a gasket clamp let go, or does a hose have a slit in it? You might want to check the source of the leak, becasue if it opens up it wont matter how many gallons of Asian pink you have, you still will not be driving.View attachment 3177900View attachment 3177901
So I thought it was a valley plate or perhaps a crack in radiator, but when I got skids off the only part of the leak was coming directly from the hose had slipped up and the clamp was loose. On the Facebook group, the lx people there said that clamp will come loose with heat. So this is a temporary tighten until I can get back home.
 
I got it as tight as possible no more puddle under the car after running it for 20 minutes. After a short drive there was the slightest drop on the skid plate but no panel. So that’s promising st least to get home safely until we can do the OEM clamp - which will require draining radiator.
 
Draining rad is easy with the petcock on the driver’s side. I’d consider putting a new radiator hose on it since you’ll have it drained and half opened anyway. The reason those clamps leak is the uneven pressure caused by the extra material added around the screw section.. this can compress the hose rubber in a way that it won’t rebound back.

Note that if you’ve been putting distilled water into it you should drain the block as well to get as much of the coolant as possible back to proper concentration. This is important for both freeze protection as well as corrosion prevention. Not too difficult with the block drains on either side.. passenger is easy to find, driver is more hidden but it is there.

Also if it’s not obvious check the upper hose for similar screw clamps.

A belief by a “mechanic” that those are better than the factory spring clamps should be an immediate indicator of hack status.

Glad you’ll be able to get home safely.
 
Draining rad is easy with the petcock on the driver’s side. I’d consider putting a new radiator hose on it since you’ll have it drained and half opened anyway. The reason those clamps leak is the uneven pressure caused by the extra material added around the screw section.. this can compress the hose rubber in a way that it won’t rebound back.

Note that if you’ve been putting distilled water into it you should drain the block as well to get as much of the coolant as possible back to proper concentration. This is important for both freeze protection as well as corrosion prevention. Not too difficult with the block drains on either side.. passenger is easy to find, driver is more hidden but it is there.

Also if it’s not obvious check the upper hose for similar screw clamps.

A belief by a “mechanic” that those are better than the factory spring clamps should be an immediate indicator of hack status.

Glad you’ll be able to get home safely.
Copy that. Yeah the top is the OEM clamp. But once I get home my buddy who is a Toyota tech and builds his own stuff offered help with just going through and making sure the clamps are right. Great idea on hose, will be good to replace to have peace of mind.

I hadn’t put any distilled water in the reservoir. Just bought a round of red 50/50 Toyota / Lexus specific coolant.
 
I only use factory clamps as well. IIRC.. the ability to consistently maintain tension over temp ranges...something a worm clamp can't do
 
So, has anyone found a way to get a borescope into the valley to check for the valley leak? I know there is some foam blocking easy access, but could a small hole be made in the foam to insert a camera without hurting anything?
 
So, has anyone found a way to get a borescope into the valley to check for the valley leak? I know there is some foam blocking easy access, but could a small hole be made in the foam to insert a camera without hurting anything?
yes, it should be very easy to push a small boroscope beyond the foam block. You can use a long screwdriver to make way instead of tearing or putting a hole.
 
Yes, you can make a small hole or simply remove the foam easily. It serves little practical purpose Imo. I had to do the valley plate leak repair 5 times in a row as my new oem toyota gasket did not sit properly no matter how i maniuplated it. It kept kinking and leaking. I ended up using an aftermarket one i had in my gasket kit that seemed identical. The first time took 8 hours, by the last time i got it down to 2 hours. I can do it blindfolded now! You wouldnt believe how often i would curse when i noticed it leak, which was sooooo obvious.

You can also tell if your coolant in the resevoir is going down, seeping around where the coolant flows through the piping into the valley or simply flashlight into the valley. Since i used an aftermarket o ring, i typically check with a flashlight into the valley every fill up. Paranoid from valley plate ptsd!
 
Yes, you can make a small hole or simply remove the foam easily. It serves little practical purpose Imo. I had to do the valley plate leak repair 5 times in a row as my new oem toyota gasket did not sit properly no matter how i maniuplated it. It kept kinking and leaking. I ended up using an aftermarket one i had in my gasket kit that seemed identical. The first time took 8 hours, by the last time i got it down to 2 hours. I can do it blindfolded now! You wouldnt believe how often i would curse when i noticed it leak, which was sooooo obvious.

You can also tell if your coolant in the resevoir is going down, seeping around where the coolant flows through the piping into the valley or simply flashlight into the valley. Since i used an aftermarket o ring, i typically check with a flashlight into the valley every fill up. Paranoid from valley plate ptsd!
Wow, what a nightmare!!! Good for you to persevere through and get it done correctly. Did you use the FIPG or a standard type gasket?
 

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