Coolant disappearing (1 Viewer)

[Grumvee]

Hi folks...

Bit of good news: the radiator stopped drinking down coolant after a fill from empty to full (1 tank) and then 2/3s more (so 1 and 2/3s reservoir tanks total). After the last fill, it's held steady, even after a drive and many hours of waiting. Phew!

I haven't had a chance to drop the skids and/or look around with a mirror and flashlight for potential valley plate leak, but will do that tomorrow.

In the meantime, my current working theory is the Lexus never filled it up all the way after the 100k service at which the coolant was apparently changed. If that's true, that means that the techs missed the low coolant at a few service visits, which seems pathetic, but totally plausible (oil changes at 105k, 110k, and 115k). And then of course at the PPI at 118k (which I know they missed). For the PPI, I don't think they even removed the engine cover things because if they did, they should have noted some seepage around the power steering reservoir/hoses as well.

My unscientific measurement / estimate of how much coolant it was low is about 0.85 quarts (out of 17.6 total quarts, per the owner's manual). If that's true, how concerned should I be that the prior owner ran it that low for ~18k miles?

Thanks again for everyone's thoughts and advice here! I appreciate it.

 

[bloc]

My unscientific measurement / estimate of how much coolant it was low is about 0.85 quarts (out of 17.6 total quarts, per the owner's manual). If that's true, how concerned should I be that the prior owner ran it that low for ~18k miles?

As long as they weren’t hard towing miles or anything I wouldn’t be worried, personally.

 

[linuxgod]

FWIW mine was the same after my radiator replacement. I ended up topping it off a few times. I assume there was air in the system which didn't bubble out until the system was run for a bit. At that point it would suck coolant in, but if the reservoir is empty then it would just suck air in and out each time it would heat/cool.

So long as the temp gauge was steady I would not be too worried. I don't think when this happens there's an air bubble trapped somewhere which would cause part of the engine to overheat while the rest was OK, it would just be a bit of air bubbles mixed in with the fluid circulating.

 

[Grumvee]

Crap. It's drinking coolant again. More slowly, but there's obviously a leak. It's down half a reservoir after a couple days and a couple of short drives.

So... I dropped the skids plates. I did find some evidence of coolant on the transmission case. But I have no idea if it is from a current leak, or from the prior leak when the prior owner replaced the radiator at 90k. Pics below.

I also tried the endoscope to get a look under the intake plenum. I didn't see anything. I think I'm looking in the right place, but if you don't mind taking a look at this video and letting me know.

Thoughts? At this point, I think I'm going to take it into a trusted shop and see if they can evaluate. Plus, obviously some repairs are needed at this point.

Thx.

 

[KLF]

Bummer.

My next step would be to clean all the residue you see, use a strong degreaser and a stiff brush. Then top it off, drive it for a few trips until you notice it has lost some more. Crawl under and look again, see if the red residue has returned.

Might also consider pulling the intake plenum. You do have to drain the coolant to do this, and technically there are a couple of gaskets that should get replaced. But they are o-ring type gaskets, you don't really need to.

 

[bloc]

You need to have a look under your intake manifold. Pretty sure you have a valley plate leak.

Other people mentioned getting a bore scope.. sometimes you can just dig out enough of the foam insulation around the PCV valve to get a look in there with a light. You can’t install new foam without the manifold off but odds are someone will need to get in there for some work anyway.

 

[supercarrera]

Yeah this is a bummer. Let's see what the shop says. Hopefully it's not the valley leak but don't really see what else it could be. It wasn't cool of a dealership to sell a car in this condition unless they legitimately didn't know it had this problem.

 

[linuxgod]

Yeah this is a bummer. Let's see what the shop says. Hopefully it's not the valley leak but don't really see what else it could be. It wasn't cool of a dealership to sell a car in this condition unless they legitimately didn't know it had this problem.

They probably did not know. It’s not obvious and in my experience dealers spend maybe 30 minutes doing a vehicle inspection before selling it

 

[Grumvee]

Thanks folks. I'll take it in to a repair shop and Monday and see what's up...

For context, I bought the car from a private seller. They had it since new. They are not car enthusiasts and relied on Lexus to service the vehicle. They brought it in for every 5k oil change, major service, and anything else that Lexus noted as even a possible item to repair. The seller is in Houston; I'm in San Jose. So we agreed that we'd have their Lexus dealer do the PPI, which I paid for. In hindsight, I should have insisted on a third party PPI.

The dealer charged me $370 for the PPI and noted zero issues.

I don't think the dealer even removed the engine cover trim because they surely would have noticed an empty coolant tank and what appears to be significant seepage around the power steering reservoir and hoses. Oh, and the passenger seat heater/ventilator/control are non-operational, and are throwing codes.

So, what did the dealer do in their PPI besides check the tires and brakes? I'm not sure. I will be speaking to them on Monday. I'm also reaching out to the seller today.

Thanks again for your help and advice, everyone. I'll let you know where this lands...

 

[Cruisin911]

Sad to say but I'll bet next round of beers that is a valley plate leak.

 

[bloc]

@Grumvee a new silicon RTV was specified for this repair. It is pretty expensive but personally I’d make sure the shop is aware, and if not I would insist it be used. I don’t have part numbers or anything but I more details have been posted elsewhere in this section.

 

[sdnative]

When I bought my LC I had the dealer that maintained the vehicle for the PO do a pre-purchase inspection. They had it for a couple hours. Came back clean with no issues. A few days later at home I noticed a cracked radiator AND signs of a valley plate leak. I complained to the dealer and Toyota corporate and the only resolution I received was a refund on the PPI. I ended up fixing everything myself and did a bunch of other stuff like WP, hoses, belt, PCV, etc while I was in there.

 

[Docboy]

When I bought my LC I had the dealer that maintained the vehicle for the PO do a pre-purchase inspection. They had it for a couple hours. Came back clean with no issues. A few days later at home I noticed a cracked radiator AND signs of a valley plate leak. I complained to the dealer and Toyota corporate and the only resolution I received was a refund on the PPI. I ended up fixing everything myself and did a bunch of other stuff like WP, hoses, belt, PCV, etc while I was in there.

Sorry to hear. How many miles on the LC?

 

[sdnative]

Sorry to hear. How many miles on the LC?

65k

 

[Tommy Dwyer]

There are far more experienced minds than mine advising here, but at the rate the coolant is disappearing I would think you‘d see wet evidence of leaking besides the dried residue underneath. When I had my radiator replaced I had a similar situation. Bought one of those cheap radiator funnel kits that fit with a gasket in place of your radiator cap. Filled it half full, started the car, turned the front and rear heat all the way up and let it run for close to an hour. Every so often I’d get bubbles in the fluid in the funnel (air escaping), eventually they stopped. Topped off the overflow reservoir and haven’t had an issue since. Might be worth a shot.

 

[blatant]

Coolant at back of engine is likely valley/heat exchanger leak. Doesn't always drip but when you jam your head - light up there, it's evident. At your rate, I would think a drip somewhere. It isn't cheap, several grand. It's a fairly big job. Cam-tower leak may be even a bigger job. Check your paperwork for whats been done.

 

[bloc]

There are far more experienced minds than mine advising here, but at the rate the coolant is disappearing I would think you‘d see wet evidence of leaking besides the dried residue underneath.

I see your point about the rate but this leak can be deceptive. It tends to pool in there then sit while the engine heat cooks the water out of it, meaning more coolant is likely escaping than what will make it all the way to the bottom.

Still not a bad idea to crank heat up and give it some revs to push air out.. but with the clear evidence of coolant along the bellhousing it had to be coming from somewhere above that.

 

[Tommy Dwyer]

I see your point about the rate but this leak can be deceptive. It tends to pool in there then sit while the engine heat cooks the water out of it, meaning more coolant is likely escaping than what will make it all the way to the bottom.

Still not a bad idea to crank heat up and give it some revs to push air out.. but with the clear evidence of coolant along the bellhousing it had to be coming from somewhere above that.

Yep, even though 65k struck me as early for valley leak the evidence seems to point that direction. I brought up the other as it was mentioned the radiator had been replaced and following that was when I experienced similar symptoms. Had my radiator and thermostat replaced and basically the dealer didn’t get all of the air out of the system. Just thought it would be an inexpensive experiment.

 

[mdh384]

I also tried the endoscope to get a look under the intake plenum. I didn't see anything. I think I'm looking in the right place, but if you don't mind taking a look at this video and letting me know.

Seems to me that you're looking in the right place to confirm the valley plate leak, although on mine the leak was further aft on the engine, which would be to the left in your video. That being said, on mine the valley area was completely full of crystalized coolant and quite clearly visible with just a flashlight from the point you accessed under the intake manifold with eyes at a level to look further aft on the engine. My engine was leaking just under 1cm on the reservoir for every ~500 miles. Mine would show drops of coolant forming on the trailing edge of the skid plate, but wouldn't ever have coolant hit the ground, and appeared to have been doing so for quite some time. There was quite a bit of white/pink droplet streaking on the underside of the vehicle from the bellhousing-aft.

You might consider squeezing the upper radiator hose after warm engine shutdown (should be firm, not hard like a rock), smelling the exhaust (should NOT smell sweet) or dropping the engine oil for a warm and fuzzy in regards to a headgasket leak.

 

[Sandroad]

Thanks folks. I'll take it in to a repair shop and Monday and see what's up...

For context, I bought the car from a private seller. They had it since new. They are not car enthusiasts and relied on Lexus to service the vehicle. They brought it in for every 5k oil change, major service, and anything else that Lexus noted as even a possible item to repair. The seller is in Houston; I'm in San Jose. So we agreed that we'd have their Lexus dealer do the PPI, which I paid for. In hindsight, I should have insisted on a third party PPI.

The dealer charged me $370 for the PPI and noted zero issues.

I don't think the dealer even removed the engine cover trim because they surely would have noticed an empty coolant tank and what appears to be significant seepage around the power steering reservoir and hoses. Oh, and the passenger seat heater/ventilator/control are non-operational, and are throwing codes.

So, what did the dealer do in their PPI besides check the tires and brakes? I'm not sure. I will be speaking to them on Monday. I'm also reaching out to the seller today.

Thanks again for your help and advice, everyone. I'll let you know where this lands...

Just catching up on this thread......and in a bad mood about that dealer......what a terrible thing to do.....they just don't care as long as they get your money. I'm sure you won't get any financial help from the dealer but after they reject all responsibility and blow you off, don't be afraid to leave them a politely negative review on review sites. They absolutely should have checked coolant level and the engine compartment for signs of trouble and run it up on a lift to have a look underneath. Do you have a checklist sheet showing they checked all the things on a PPI and signed by a tech? If so, and they checked the coolant level box, that will help your case, but in the end won't do you any good. They may not have known about a coolant valley leak, but that's because THEY DID NOT CHECK THE COOLANT LEVEL!

OK, rant over. Bummer about your troubles. You did everything right and none of this is your fault. Get it all fixed up and enjoy that wonderful LX for a long, long time.