Coolant Loss Quickly

Hi guys, first post here but excited to join the community. I have an 04 V6 4WD 4runner that is currently losing coolant very fast. I have got oil samples when changing oil and they said there were small amounts of coolant in the oil but nothing major, and it hasn't done damage to the engine with signs of abnormal wear. This lead me to checking my coolant level a few days back.

After checking the coolant level in the reservoir, there was hardly any coolant in there. I filled it up to the max fill line and 4 days later with not even 100 miles driven since, and coolant levels are back to almost nothing. Never been any overheating at all. Just filled the reservoir back up with coolant and have a piece of cardboard placed under the vehicle to try and see noticeable signs of a leak. I know some possible things are head gasket or water pump. Hoping for my sake it's not a head gasket, but is there anything else I should do to check to know for sure what's causing it? Any and all help/comments would be greatly appreciated, thank you!

 

Is there any white smoke coming from the exhaust?

It's running fine?

 

Since you say there coolant in your oil, unfortunately it sounds like a head gasket.

With that much coolant lost and some in the oil, you should notice at least 2 other symptoms, one being as mentioned white "smoke"/steam from the exhaust, the second is oil level over the maximum level, the oil level might not be all that noticeable IF your oil level before this coolant lost issue was normally a 1/2 to 1 quart low when your regularly schedule oil change is due which seems to be sorta normal for some 4TH Gens but not all, if that was the case prior to this issue you may now notice the oil level lost is not as bad as before the coolant issue.

That being said you can check each cylinder with a borescope through the spark plug holes after sitting over night for coolant on top of the piston/s.

 

Second of the possibility of a head gasket. Do you have access to a pressures tester which you could use to pressurize the system, when not running to check/inspect for leaks?

 

Pre 06 V6 losing coolant, RIP. Get the head gasket done before you warp a head. Involves having the heads machined also.

 

@Thatbassguy I haven't noticed much white smoke out of the exhaust and it still runs perfectly fine.

@AuSeeker Haven't noticed much white smoke out of the exhaust but I will specifically look for that. Should I look more for it when I first start it up or while I'm just doing normal driving around? I will check each cylinder tomorrow for coolant and give an update.

@RumHamRunner73 I do not currently, but I can get access to one probably tomorrow.

@GreatWhitePig If it is for sure head gasket, do you have a general idea of how much it will cost? And if it has already gotten bad enough to warp a head would I already know if that has happened? I have only had this for about 11 months and it has 280,000 miles, so just trying to figure out if it would even be worth it to put the money into it.

Thank all you guys for your input already, I really appreciate it.

 

Also update: the coolant I put in the reservoir to max line about 6 hours ago with only about 15 miles of driving and it is already to the min line with no huge amount of coolant on the ground

 

This is also my oil analysis from the 2 times I have changed the oil in it if this provides anyone will some more info.

 

@AuSeeker Haven't noticed much white smoke out of the exhaust but I will specifically look for that. Should I look more for it when I first start it up or while I'm just doing normal driving around? I will check each cylinder tomorrow for coolant and give an update.

@RumHamRunner73 I do not currently, but I can get access to one probably tomorrow.

@GreatWhitePig If it is for sure head gasket, do you have a general idea of how much it will cost? And if it has already gotten bad enough to warp a head would I already know if that has happened? I have only had this for about 11 months and it has 280,000 miles, so just trying to figure out if it would even be worth it to put the money into it.

Thank all you guys for your input already, I really appreciate it.[/QUOTE]

First thing when you start it after sitting all night is when there would be coolant in the cylinder/s, so that's when it would smoke the most.

Have you check the oil level, if the coolant is getting into the oil I would think the oil level would be overfilled.

 

First thing when you start it after sitting all night is when there would be coolant in the cylinder/s, so that's when it would smoke the most.



Have you check the oil level, if the coolant is getting into the oil I would think the oil level would be overfilled.[/QUOTE]

Yes oil level is fine and looks just like oil with no coolant in it, but I guess it could be due to me just recently changing it less than 1,000 miles ago.

 

You need to crawl under it and see if coolant is being blown back underneath the truck. It would be white/pinkish in color, assuming factory coolant is being used. If it is, then there is an external leak. If not, then you need to do tests to see if it's a head gasket. Compression test, leak down test, to start and check for oil in the coolant. You already know there is coolant in the oil.

 

UPDATE: After parking in a different spot with cardboard underneath always, it was very easy to notice an external leak. I did go ahead and do a combustion leak test and the liquid stayed blue after pumping for a couple minutes at operating temperature. I will be doing a pressure test here in the next couple days to try and find directly where the leak is coming from

 

Negative on your external leak comment. You need to physically inspect underneath to determine that, honestly. It could be getting caught on the skid plate and not dripping at all or blown back and dry up before it can drip on the ground. Cardboard test is convenient but a lazy way to test.

 

Unfortunately, all I have are ramps at the moment and it’s hard to tell exactly where it’s leaking from without getting a great view of underneath but it is very noticeably leaking and dripping on the ground. Would you recommend I do a pressure test on the cooling system to help find where the leak is exactly coming from or is there something else I should do first instead?

 

Apologies, I re-read what you previously wrote and see that you did actually say you saw an external link. My mistake there.

You might be at the point of needing to have a shop do an inspection for you with the truck on a lift so that they can make the determination of exactly where the leak is coming from. You know there is some sort of leak now, no sense in doing a pressure test until that is fixed.

 

Check the water pump.

 

Update after a couple of days: Lots of coolant all on passenger side, near radiator and water pump and a lot of it got slung back underneath and on skid plate. Hard to tell exactly where the source is. Going to remove the skid plate tomorrow and clean up as best I can so I can hopefully see better where it’s leaking from directly. May also rent a pressure tester as well

 

This is an irrelevant question to the problem but out of curiosity was checking pH of coolant and changing coolant periodically part of the truck maintenance ?

 

I’ve only had it for about 10 months and hadn’t checked the pH level or done a coolant change yet but had been regularly checking the level. Turns out to be my radiator after doing a pressure test. I will do a full flush of the system then replace the radiator and thermostat along with new hoses and clamps

 

Also just a general question if anybody happens to see this. With doing the pressure test it was very evident to see it leaking from the radiator. With my oil samples coming back with small traces of coolant in my oil, would that still mean I could have a head gasket issue or is there other things besides that can cause coolant to get into oil? Once again, no white smoke, overheating, rough idle, or any large amounts of coolant in oil to cause the oil to look frothy or sludged up.