Disappearing Coolant + White Smoke = Head Gasket Replacement

[Packofcrows]

Originally Posted by jawn

Have you logged your coolant and oil temps?

I am. I lose liquid too and have zero idea where it goes. My 22re does the same. I just DD it and pay attention to my fluids. Oil is fine, just coolant.

21k here, no worries yet. Gonna driver it hard for next 2k if I do hear or feel something odd. Have warranty till 25k.

[Cal3000]

Originally Posted by jawn

Have you logged your coolant and oil temps?

I just tool a log today. I filled up this morning with coolant. Did a hard run. Seems like I lost a lot of coolant. It's having a hard time keeping the temp down.
Compared to [previous logs from last year, coolant shouldn't be having any issues. Oil temps went as high as 119 C last year and the coolant maintained 92-99C. Oil temps are the same levels and the coolant is heating up like crazy from day to day.

BTW, my car isn't stock

[Ultramaroon]

Originally Posted by Cal3000

At 100k miles, I seem to be having this same issue. After high RPM driving from day to day, I seem to lose 0.5L of coolant every day. I don't lose as much under normal driving. After a hard drive, the overflow tank is overflowing like crazy. It's becoming annoying. No warranty=expensive repair.
I took my car to a Midas and they did a hydrocarbon test for the coolant and didnt find anything.
I don't know what's going on. lol

It's your radiator cap. That's all. Obvious sign is the reservoir overflowing. Pressure loss leads to boilover.

Replace the radiator cap and bleed out ALL the air. The bleeding process is super important. Do not neglect it. If you don't know how, leave it to a pro.

[jawn]

Originally Posted by Cal3000

I just tool a log today. I filled up this morning with coolant. Did a hard run. Seems like I lost a lot of coolant. It's having a hard time keeping the temp down.
Compared to [previous logs from last year, coolant shouldn't be having any issues. Oil temps went as high as 119 C last year and the coolant maintained 92-99C. Oil temps are the same levels and the coolant is heating up like crazy from day to day.

BTW, my car isn't stock

For how long have you been losing coolant? How long have you been boosted? Could be a water pump or a thermostat if it used to run fine with your current set of mods. Are you only losing coolant from the overflow? I guess I would check around the water pump and see if you have any signs of lost coolant from there, or check to see if coolant is flowing to/from your radiator. If, for whatever reason, the pump isn't operating correctly, you won't feel water moving through the radiator hoses while the car is running. They'll be hot, so you might want to wear gloves.

My last car (which wasn't an 86) used to eat water pumps every year, so I'd lose like a quart of coolant after driving it when the pump started to fail. After you park it, see if you're leaving coolant on the ground.

White smoke is a pretty good sign that you have a gasket issue, but absent that, and with the hydrocarbon test coming back ok, you're *probably* not dealing with a bad gasket. I'd look at the other parts of your cooling system, especially with your mileage. Hopefully it's something relatively painless.

[jawn]

Originally Posted by Ultramaroon

It's your radiator cap. That's all. Obvious sign is the reservoir overflowing. Pressure loss leads to boilover.

Replace the radiator cap and bleed out ALL the air. The bleeding process is super important. Do not neglect it. If you don't know how, leave it to a pro.

LOL. I might have overthought it.

[Ultramaroon]

Originally Posted by jawn

LOL. I might have overthought it.

Meh. All well intended.

[Coheed]

Originally Posted by Ultramaroon

It's your radiator cap. That's all. Obvious sign is the reservoir overflowing. Pressure loss leads to boilover.

Replace the radiator cap and bleed out ALL the air. The bleeding process is super important. Do not neglect it. If you don't know how, leave it to a pro.

For some reason or another, these MLS gaskets seem to leak at higher rpm occasionally. I've seen all sorts of engines have these kinds of issues where they are just fine until beat up a bit. They can be very hard to diagnose. If combustion gas is transferring into the cooling system, the radiator cap will vent and cause the tank to overflow.

I've seen it on 500hp stock cars, and 120hp stock cars. Modifications withstanding, I don't have a lot of faith in the MLS gaskets being better than the old school composite gaskets. I know many people will flame me for that statement, but I've used composites in all manners of road vehicles without these issues. MLS gaskets I've used in the past seem a lot less reliable. I wonder if the gaskets are just cheaply made, or if they just don't seal as well as the old stuff?

[Cal3000]

Originally Posted by Ultramaroon

It's your radiator cap. That's all. Obvious sign is the reservoir overflowing. Pressure loss leads to boilover.

Replace the radiator cap and bleed out ALL the air. The bleeding process is super important. Do not neglect it. If you don't know how, leave it to a pro.

Radiator cap was the first thing I did. Been through 2 new ones within 3 weeks. Still have the same issues. It has to be something else. lol

[Cal3000]

Originally Posted by jawn

For how long have you been losing coolant? How long have you been boosted? Could be a water pump or a thermostat if it used to run fine with your current set of mods. Are you only losing coolant from the overflow? I guess I would check around the water pump and see if you have any signs of lost coolant from there, or check to see if coolant is flowing to/from your radiator. If, for whatever reason, the pump isn't operating correctly, you won't feel water moving through the radiator hoses while the car is running. They'll be hot, so you might want to wear gloves.

My last car (which wasn't an 86) used to eat water pumps every year, so I'd lose like a quart of coolant after driving it when the pump started to fail. After you park it, see if you're leaving coolant on the ground.

White smoke is a pretty good sign that you have a gasket issue, but absent that, and with the hydrocarbon test coming back ok, you're *probably* not dealing with a bad gasket. I'd look at the other parts of your cooling system, especially with your mileage. Hopefully it's something relatively painless.

I guess I'd have to overhaul the whole cooling system. If that doesn't work, everything will point to a head gasket. Was your water pump failure obvious as with leaking?

[jawn]

Originally Posted by Cal3000

I guess I'd have to overhaul the whole cooling system. If that doesn't work, everything will point to a head gasket. Was your water pump failure obvious as with leaking?

Eventually. It'd start small, and then end with a pool of coolant under the car.

[Ultramaroon]

Originally Posted by Cal3000

Radiator cap was the first thing I did. Been through 2 new ones within 3 weeks. Still have the same issues. It has to be something else. lol

Have you bled out the air after these boilovers? If a big air pocket exists fluid flow is restricted. Then you just get more boilover.

[Ultramaroon]

Originally Posted by jawn

Eventually. It'd start small, and then end with a pool of coolant under the car.

Maybe I underthought it.

[Cal3000]

Originally Posted by Ultramaroon

Have you bled out the air after these boilovers? If a big air pocket exists fluid flow is restricted. Then you just get more boilover.

Do you mean that vent screw near the firewall?

[notout86]

Apart from air pockets in the cooling system it is seldom realised that fresh coolant, especially if prepared from concentrates diluted with water will contain dissolved gases from air. These gases will be driven out when the coolant is heated in the cooling system and when eventually expelled to the overflow bottle , the level will drop which may be puzzling until fully expelled.
If the water used for dilution is first boiled in a container that will not introduce minerals (e.g. use stainless steel) the gases are driven out. Cover and allow to cool so the air re-absorbed is minimised then use. The re-absorption is slow if the water is kept still.

Reducing the dissolved oxygen this way will reduce oxidation too.

A small surface area of coolant in the overflow bottle helps reduce air absorption too.