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Mine was taking a couple months to drop before I created new leak with poor sealing job, but it was leaking somewhere else before I took the starter out This is when
I relized my overflow hose was separated from the engine so the oolant level in overflow never changes it’s above engine level Can’t escape out leaking hose Only engine coolant would leak here from hot water rising and pumped by engine water pump.
When I began taking stater out I only got less than a gallon from radiator
Should have been gallon and half at least When done with stater I ended up Putting about two gallons into engine not overflow tank cause it was full Engine was low but would not know if I did not have to drain it to repair starter
LS 215k miles1996
Hmm ok, I will have to check the coolant in the engine and see if the overflow tank is not putting coolant in the engine.
[QUOTE=OneLSowner;10090544]
Originally Posted by winter4w
Reading a bit more online I am wondering if I have air stuck in my heater core. The only thing that is stumping me a bit is it seems when people have air in the cooling system their coolant levels drop. Mine doesn't drop, it still remains at the full mark (which is good).[/QUOTE
your engine could be pumping coolant to tank but the vacuum needed to draw back into engine is not there and engine level could be low
Have to remove large bolt on top of water pipe out let and fill with coolant
Ok thanks, I will have to go pick up some Toyota red coolant then.
So is there a way I can check to see how much is in the engine and if I put more coolant in how would I know how much to put in it before it is full?
Test 2: Ok so I was able to reproduce the issue sitting for 5-10 minutes in my driveway and at a parking lot. When the engine was starting to go above normal temps I set the climate controls to HOT and it still blew cold air. I went to look under the hood and noticed the small fan in front of the radiator was not running at all. After about a minute of it nearing the 3rd line, it began to cool down. Earlier today while waiting in the parking lot I noticed it going up again. Again I went to look under the hood and that fan was not on. The big white fan in the back of the radiator was on. Is this fan suppose to run when idle and the engine is warm? Once I started driving in the parking lot under 5MPH the temp started to go down.
Here are some images I got of how hot it got before I started driving it.
The big bolt is removed on top of water outlet 17mm size bolt then fill till it comes over the top or close to it without spilling over the front fan That fan I believe runs all the time off of the belt Have to go out and look for secondary fans on radiator like most cars but never seen on my. Just the constant fan running off the serpentine belt.
Isaw Autozonesell coolant that mixes with all colors but good to keep yours red color for finding leaks on the ground
[QUOTE=winter4w;10090963]Hmm ok, I will have to check the coolant in the engine and see if the overflow tank is not putting coolant in the engine.
Originally Posted by OneLSowner
Ok thanks, I will have to go pick up some Toyota red coolant then.
So is there a way I can check to see how much is in the engine and if I put more coolant in how would I know how much to put in it before it is full?
Test 2: Ok so I was able to reproduce the issue sitting for 5-10 minutes in my driveway and at a parking lot. When the engine was starting to go above normal temps I set the climate controls to HOT and it still blew cold air. I went to look under the hood and noticed the small fan in front of the radiator was not running at all. After about a minute of it nearing the 3rd line, it began to cool down. Earlier today while waiting in the parking lot I noticed it going up again. Again I went to look under the hood and that fan was not on. The big white fan in the back of the radiator was on. Is this fan suppose to run when idle and the engine is warm? Once I started driving in the parking lot under 5MPH the temp started to go down.
Here are some images I got of how hot it got before I started driving it.
If you are convinced your water pump, radiator and fan clutch are in good condition, then check the integrity of seals of your firewall mounted water control.valve.
Wrap a paper towel around it to see if it stains red from coolant leaks.
I still hold firm that the cooling system needs to be bled and/or more coolant added. I got my car in AZ during November when it was pretty cold out and it still started overheating like yours was.
I would remove that large 17mm fill bolt, start the engine with the radiator cap off, and start filling coolant through that hole. You'll probably need to run the engine at 2500 rpm to get it circulating throughout. But i'm almost certain you're low if your gauge is going up that much.
I don't remember, but did you say you replaced your radiator recently? The previous owner of my car replaced the OEM Radiator with a Denso purchased off RockAuto for $60-70 and its been trouble free for over 35k miles since I got the car at 253k....I think he did it at 245K back in 2015. I'm not even using a Lexus rad. cap, just a crappy MotoRad lever release style and its holding pressure well.
After seeing how high the gauge goes and hearing that it does go down when you drive, (raising RPM) you definitely have air in the system. Most people park the car facing up hill a little so when you remove the 17 mm bolt on top of the t-stat housing the air will come out, also where to fill it. Also with that bolt out you can see the coolant flowing. This way you know if the t-stat is opening and the water pump is working.
The fogging of the windows I usually get the greasy film on the windsheild and two front windows. My 93 the film was on ALL the windows b/c the heater core was so bad. Before I changed my HC I was washing the windows every other day just so I could see enough to drive.
Try bleeding the system again before thinking it's the HC b/c yes, that is not a job you want to do just for the hell of it.
The big bolt is removed on top of water outlet 17mm size bolt then fill till it comes over the top or close to it without spilling over the front fan That fan I believe runs all the time off of the belt Have to go out and look for secondary fans on radiator like most cars but never seen on my. Just the constant fan running off the serpentine belt.
Isaw Autozonesell coolant that mixes with all colors but good to keep yours red color for finding leaks on the ground
Yea I got the Toyota red coolant in it, however, have yet to see any leaks. I got an old carpet under the car in case a leak occurs.
[QUOTE=YODAONE;10091601]
Originally Posted by winter4w
Hmm ok, I will have to check the coolant in the engine and see if the overflow tank is not putting coolant in the engine.
If you are convinced your water pump, radiator and fan clutch are in good condition, then check the integrity of seals of your firewall mounted water control.valve.
Wrap a paper towel around it to see if it stains red from coolant leaks.
Originally Posted by Losiracer2
I still hold firm that the cooling system needs to be bled and/or more coolant added. I got my car in AZ during November when it was pretty cold out and it still started overheating like yours was.
I would remove that large 17mm fill bolt, start the engine with the radiator cap off, and start filling coolant through that hole. You'll probably need to run the engine at 2500 rpm to get it circulating throughout. But i'm almost certain you're low if your gauge is going up that much.
I don't remember, but did you say you replaced your radiator recently? The previous owner of my car replaced the OEM Radiator with a Denso purchased off RockAuto for $60-70 and its been trouble free for over 35k miles since I got the car at 253k....I think he did it at 245K back in 2015. I'm not even using a Lexus rad. cap, just a crappy MotoRad lever release style and its holding pressure well.
Yea I am started to think too there is air in the system. My radiator hasn't ben replaced but my water pump was replaced around 120K (When I bought the car). If I am low on coolant why is my reservoir not going down? And I think I got the original cap seeing its the same cap on other LS400's. I've attached some images below.
Originally Posted by deanshark
After seeing how high the gauge goes and hearing that it does go down when you drive, (raising RPM) you definitely have air in the system. Most people park the car facing up hill a little so when you remove the 17 mm bolt on top of the t-stat housing the air will come out, also where to fill it. Also with that bolt out you can see the coolant flowing. This way you know if the t-stat is opening and the water pump is working.
The fogging of the windows I usually get the greasy film on the windsheild and two front windows. My 93 the film was on ALL the windows b/c the heater core was so bad. Before I changed my HC I was washing the windows every other day just so I could see enough to drive.
Try bleeding the system again before thinking it's the HC b/c yes, that is not a job you want to do just for the hell of it.
Yea my window will fog every month or two and it's just the windshield. Reading online on other posts it seems its a pain to wash too, the stuff I'm cleaning is easy. I also cleaned it up a few days ago to see if it would return and it hasn't. So now I am thinking its air too.
Ok so I have attached some pictures below of my reservoir and the bolt. So just to make sure I am going to bleed it right:
1. Undo the bolt
2. Open the cap on the reservoir
3. Rev the car @ 2500rpm for 5 minunts
4. Stop the car and put the bolt and cap back on
5. Fill the reservoir if coolant levels drop
So just to confirm are those the steps I would need to take?
and is this the bolt I would need to take off?
And here are pictures showing my reservoir is showing full:
Looks like your almost there.
Carpet under car won’t do. You need smooth whitesurface to see leaks Carpet absorbs . An Tupperware lid fron plastic storage containers like that slide under bed will do or plastic trash can Iid. Also let . let run 1/2 hour hood closed helps with quicker heat up.
istill smell coolant from mine but never worry I can pop open the 17 mm bolt add more if gets slightly hot till find leak
Air is no problem when filled slowly while running or not. It is getting pushed out opening on top of engine when you fill this way, but going slowlyslowly does it or better to let run when filling. This pumps air out and up out of water, and not rely on gravity only to get air out . Your not trapping air pockets in engine block this way, engine running.If coolant never gets behind thermostat,It will overheat in 15 min after running if there is airpocket behind thermostat. If there is no water water touching thermostat, to heat up and open thermostat., it won’t open to prevent overheat. Any air hot air will not open thermostat, it needs 175 degree water.
But start job cold or slightly warm to avoid any hot water spraying out when removing bolt.
You got right bolt. It has shim but mine not leaking at that point though. But should replace shim too after breaking the bolt loose.
Looks like your almost there.
Carpet under car won’t do. You need smooth whitesurface to see leaks Carpet absorbs . An Tupperware lid fron plastic storage containers like that slide under bed will do or plastic trash can Iid. Also let . let run 1/2 hour if need Hood closed helps with quicker heat up.
istill smell coolant from mine but never worry I can pop open the 17 mm bolt add more if gets slightly hot till find leak
Air is no problem when filled slowly while running or not it getting pushed out opening on top of engine when you fill this way
You got right bolt. It has shim but mine is not replaced yet for a better seal when tight. No leaking at that point though. But should replace shim too after breaking the bolt loose.
Well, I was more looking for a red fluid on the ground if there is a leak. I am still confused on how I would go about getting air out the system. Today I went and took the cap off the reservoir and let the car run at 2000RPM for a few minutes after the engine warmed up. There were no bubbles or coolant level drop. While doing it the temperature remained right on the middle line. Heter was also blowing warm air at idle but not hot. I then turned the car off, put the cap on and waited until tonight. Went to drive her around to see if everything was ok and ran into the same issues. Heater blew cold air under 2000RPM and temp started to go up. Even driving at a slow speed it still climbed to the top line (I never watched to see if it would hit the H). So did I burp the system right?
When removing engine fill point bolt, the air escapes, that is the reason it is there, to fill the ENGINE and remove air. Notice how it’s above overflow tank too? Highest point for air to escape and system have nothing but coolant no AIR
The overflow tank never comes into play it’s for expansion of water from engine to save and pull back in when cool it works by suction and No water fills the engine by suction till the cool down of engine overnight. It also has an airspace the full line is down a ways on tank. But engine is all coolant it’s full with no airspace highest point is up there on top so no air space.
. So you need to remove bolt and force coolant I nto engine forcing any air out in its place. The suction only works with the cooldown
Air is the result of leaking coolant system. Not working right.
I’m beginning to think your head gasket is compromised if you never see coolant. It is going out exhaust pipe!,,
When removing engine fill point bolt, the air escapes, that is the reason it is there, to fill the ENGINE and remove air. Notice how it’s above overflow tank too? Highest point for air to escape and system have nothing but coolant no AIR
The overflow tank never comes into play it’s for expansion of water from engine to save and pull back in when cool it works by suction and No water fills the engine by suction till the cool down of engine overnight. It also has an airspace the full line is down a ways on tank. But engine is all coolant it’s full with no airspace highest point is up there on top so no air space.
. So you need to remove bolt and force coolant I nto engine forcing any air out in its place. The suction only works with the cooldown
Air is the result of leaking coolant system. Not working right.
I’m beginning to think your head gasket is compromised if you never see coolant. It is going out exhaust pipe!,,
Bad news
Originally Posted by OneLSowner
I’m thinking your leak is inside on carpet
Sorry I only now read some of your other post
Carpet damp?
Its hard to feel on top cause the insulation is thick
I am probably just going to take it to my mechanic to see whats wrong. I usually do the small work myself but it seems like I would have to dig around and find what the issue us. Unfortinoly I need this car ASAP since it is my only daily driver. I don't think my head gasket is compromised since I would see a lot of signs like milky oil. I always check the oil every week since she does drip some oil.
I will post back what gets discovered and what work gets done. She is close to 150K (149,650 Miles) miles so will probably get all that work done too.
Not True.
Yourhead gasket can be leaking at the area where only water passes thru.
Pulling a few plugs and looking at them tells everything you need to know going on in your engine.
And do do compression test very easy
its like getting blood pressure test every year.
Your engines blood pressure 175 PSI give or take 10%
Good Luck
i don’t know why you can’t pull the 17 mm off and fill your coolant?
I highly doubt that your head gasket is bad. (Very uncommon in LS400) Even if it was burning out the exhaust you would notice a drop in the reservoir.
When I bleed mine I get it to normal temp. (so the t-stat opens)
Turn heat on at max temp
Wrap the T-stat housing with rags. (to soak up lost coolant when bolt is removed)
Remove 17mm bolt on top of T-stat housing. (Slowly, b/c of pressure)
Raise RPM to about 2000 and make sure I see coolant flowing inside that 17mm bolt hole.
Using funnel in the bolt hole, add coolant slowly til full.
Remove funnel and replace bolt.
I leave RPM up until the 17mm bolt is back in and tightened.
Not True.
Yourhead gasket can be leaking at the area where only water passes thru.
Pulling a few plugs and looking at them tells everything you need to know going on in your engine.
And do do compression test very easy
its like getting blood pressure test every year.
Your engines blood pressure 175 PSI give or take 10%
Good Luck
i don’t know why you can’t pull the 17 mm off and fill your coolant?
The signs of a failed head gasket I am not seeing and my coolant levels have remained the same. I did get her back from the shop and posted what was wrong below
Originally Posted by deanshark
I highly doubt that your head gasket is bad. (Very uncommon in LS400) Even if it was burning out the exhaust you would notice a drop in the reservoir.
When I bleed mine I get it to normal temp. (so the t-stat opens)
Turn heat on at max temp
Wrap the T-stat housing with rags. (to soak up lost coolant when bolt is removed)
Remove 17mm bolt on top of T-stat housing. (Slowly, b/c of pressure)
Raise RPM to about 2000 and make sure I see coolant flowing inside that 17mm bolt hole.
Using funnel in the bolt hole, add coolant slowly til full.
Remove funnel and replace bolt.
I leave RPM up until the 17mm bolt is back in and tightened.
Awesome I will give it a try if I run into any more temp issues
Reply to Everyone:
So got her back from the shop and the issue was the fan clutch. Now that it has been repaired I am getting warm air at idle when setting it to hot and the temperature is staying normal at idle . I also forgot the loud roar she makes with it fixed. I would like to thank all of you for trying to help me solve this and if anyone comes across this thread with the same issues hope it helps them too
01-23-18, 11:44 AM
