'06 GS 300 - Coolant is blowing out from the overflow hose, but the engine temp is always normal.

I was under the car today and noticed fresh coolant on some of the hoses and other parts drivers side. I could see where it has been doing this for a while because there were a lot of dried up spots. I do not see any leaks in or around the radiator and the engine temp is always normal. The reservoir level is "Low". It appears that the coolant is coming from the overflow hose on the reservoir. Should I be concerned?

 

Yes you should. Clean all the dried up coolant around the area then file the coolant up to the high line in the morning when the car is cold. Keep checking the level for the next couple of days.

 

I wouldnt drive the car! You can easily destroy the engine by warping the heads. When was the last time you replaced the water pump and thermostat?

 

Coolant expands when hot and contracts when it cools.

If its expanding so much that it spills out then it may be getting way too hot.

possible cause is thermostat not opening on time. But in that case you will see higher coolant temps. And you said its normal temp..soo.. its possible that the cap isnt holding the right pressure and coolant goes to the overflow and then spills out...

i think its gonna be the cap. But monitor the coolant temp values if its at 80c or whatever it should be then thermostat is working




yes mr white! yes science😀!

 

Issue resolved

Radiator Cap -
NOTE TO SELF: This car does not have a "Radiator Cap", there is no cap on the radiator. There is, however, a cap on the thermostat housing. Name of cap should be "Coolant Cap".

 

If you have original water pump and thermostat, I would replace it with a aisin (its oem rebrand) brand from rockauto.com. Its preventive maintenance if the water pump locks up it can destroy your motor. Usually on 3gs the water pump spits out pink slime at around 90k miles. There have been members on here that have destroyed their engines from not replacing the water pumps. A quick way to find out if you water pump is leaking, reach behind the water pump pulley and wipe the back off, if theres a lot of pink slime know that its been leaking and eventually will fail. I replaced mine at 100k and it had slime built up

 

Preventative maintenance is good to a certain degree. Unless one is oblivious, no need to be paranoid and replace water pump prematurely. You will see it coming *literally* from 10,000 miles away..it will make noises and you will see coolant dissapear.

On my corolla the original pump lasted 220,000km. It was making grinding sounds for a YEAR. For a year i didn't lose any coolant. Then one day I noticed a puddle when idling, opened the hood and the pump was squirting.. Even in that state it would lose coolant pretty slowly. I drove like that for a few days topping up the coolant reservoir every 50km or so.. When coolant dissapears from the engine is gets sucked in from the overflow tank so it's not like theres no coolant in the engine...and it won't just seize up out of the blue.. it will make bad noises long before it does that. and even if it does seize the belt will slip off and you will know it..

I don't know what happens if the belt slips off on a toyota, but on BMW if the belt slips off and you keep driving, shredded pieces go behind the crank pulley destroying the seal and go inside the engine, block the oil pickup, and the engine blows. Then these people go and talk smack about BMW

 

Considering the majority of oem pumps go out at 100k miles. I changed mine at 110k, now I have about 190k miles, I have about 80k miles on my aisin pump, there only $80-100 for the kit. Only takes 2-3 hours to install, its not very difficult i did it myself. It's cheap insurance, plus it gives you assurance so you dont have to worry about your water pump. A pump can easily go out while youre on the highway say for a road trip. Imagine being stranded or worst stranded with a blown engine. Its happened to several members on here.

 

I wish it left me stranded so I could get a day off work...I would attempt to just fix it on the road and not go to work haha.. im currently driving with a leaking radiator. it got bent in the little crash I had.(not my fault, got brake checked HARD). Cold weather hit and I noticed some coolant in my engine bay and was losing small amounts. Gave it a pressure test and coolant seeped at the seam(plastic and alu crimp point.) Now it got warmer and it stopped leaking. I am not losing any coolant.

I like oem parts but im kinda tempted to get the cheaper one on rockauto. CSF brand to be specific. It has the "heart" logo (i doubt it correlates to quality in any way.) its just the cheapest one in the "standard replacement" section so people go for it. Im not savage enough to buy the ULTRA POWER.

Denso is only $130CAD, $40 more expensive than CSF. That's like 4 days of gas or a weekend of drinking beer. So I thnk I will buy the denso.

literally love this car, so comfortable, so smooth, kinda powerful, parts are cheap. I wanna keep it until its obsolete then get an electric.. yea econoboxes are good for your wallet but they dont go 120-150km/h engine barely turning just cruising along getting decent economy, they don't dominate in snow, they don't have casette deck. oh yeah i bet theyre jealous.

 

I bought this car last year with only 36k mi. I now have about 52k on it. I have a little ways to go before a water pump change. I have a 1hr commute one-way daily. Drove it yesterday and the reservoir didn't loose anything. Thanks for all the input, I will keep the water pump issue in mind. I will set a reminder on my calendar for it!

The only issue I can see is a small oil seep from the valve cover gasket. I will work on that one soon . . .

 

Take it to a radiator shop, my radiator leaked and it turned out to be the top rubber seal. I purchased a seal from the dealer and they installed it for me for next to nothing. But a leak at the top of a radiator is totally different then a bad water pump. Your pump is still pumping that coolant, with the heat the thermostat will open and coolant is getting circulated. But if that pump fails, then that waterflow will stop, and because you have a leak slowly you will steam out the coolant until it is empty.

 

Wow thats crazy low mileage! But I would still change out the water pump, as its the seals that go bad, like your radiator cap going bad, my cap went bad at 170k miles. Or atleast keep an eye on it like I mentioned run your hand behind the water pump pulley and if theres a lot of pink slime then that pump has been weeping. A little pink is ok, but a lot if bad

Also what mileage are you changing your oils at? For an 2006 they are plagued with carbon build issues. So personally I would do oil changes at every 3k miles, many people who have oil consumption issues run their oils at 5-10k miles. Also after every 2nd or 3rd oil change run a top induction cleaner spray through the nipple on the intake manifold. Super easy just get the car nice and hot, pop off the engine cover, buy a can of seafoam spray with the nozzle. Pop off that blank nipple thats on the intake manifold while the engine is running. Quickly place the nozzle inside and spray in the full bottle, doesnt take more then a few min. This will help clean your intake valves, make your car run better and more fuel efficient.

 

UPDATE: Found the issue with the coolant coming out of the overflow line
It's amazing how stupid things can be the most difficult to see. . . . . . . the lines were connected to the wrong nipples on the overflow tank cap!
Line from motor went to the vent nipple, and the vent line went to the tube that goes to the bottom of the tank. It was blowing in hot air and pushing the coolant out.

I just happened to look at it when I was filling the tank back up . . . .