Slowly losing (and smelling) coolant

[PantsDants]

I've seen a bunch of posts related to coolant consumption and smelling it after long-ish drives on the highway, but I've yet to see any sort of resolution in terms of finding leaks or whatever, so I figured I'd post this up to attract people who may have had similar experiences.

My coolant is below the low line when cold, and about an inch or two above it when hot (~9000 miles on the car). After driving on the freeway for around 15 minutes or so and parking it, I can smell coolant when I get out. It doesn't come through the vents or anything, just outside the car, and the smell quickly goes away.

So my questions are as follows: Where have coolant leaks been found? Or is this really just evaporation of the coolant happening due to the high under hood temperatures? I was thinking of installing the FXT oil cooler sometime soon, but if I don't get any usable feedback, I'm gonna have to take her back in to the dealer to figure this out.

I really just need an idea of where to start looking, if I should even worry about it. Thanks guys.

[strat61caster]

http://www.ft86club.com/forums/showthread.php?t=36150

[humfrz]

Originally Posted by PantsDants

I've seen a bunch of posts related to coolant consumption and smelling it after long-ish drives on the highway, ...........So my questions are as follows: Where have coolant leaks been found? Or is this really just evaporation of the coolant happening due to the high under hood temperatures? I was thinking of installing the FXT oil cooler sometime soon, but if I don't get any usable feedback, I'm gonna have to take her back in to the dealer to figure this out.

I really just need an idea of where to start looking, if I should even worry about it. Thanks guys.

Well, I see ol strat61caster pointed you to a very long thread with lots of background information....

I would start by making sure the coolant drain petcock was tight and not leaking. Also check the radiator cap and overflow container caps. If you see/smell coolant around those caps, a bit of petroleum jelly on the seals may prevent them from leaking.

Unless you can see coolant outside of the system, I wouldn't worry about it.

humfrz

[orod35]

Ive had the same problem and actually have seen coolant sprayed on the inside of the engine bay. Couldnt find the leak myself so i took it to the toyota dealer. They told me they found a pinhole leak in the radiator in front of the ac condensor. They tell told me it was caused by an impact due to a crash. What i dont get is how could that have happened and nothing happened to the ac condensor.

[wbradley]

Are you sure you aren't smelling the oil drip from the rear passenger side cam area on the exhaust manifold? That is a very common and benign occurrence with the twins. I topped up my coolant a bit after my second season. No huge worry as I don't see it leaking anywhere. Just hope nothing happens after the 3 year warranty runs out.

[PantsDants]

Originally Posted by wbradley

Are you sure you aren't smelling the oil drip from the rear passenger side cam area on the exhaust manifold? That is a very common and benign occurrence with the twins. I topped up my coolant a bit after my second season. No huge worry as I don't see it leaking anywhere. Just hope nothing happens after the 3 year warranty runs out.

Good suggestion. The thing is though that I've checked my oil level fairly regularly and it hasn't budged at all, though I suppose one or two drips would be enough to get a noticeable smell. I just assumed it was coolant as that has been visibly disappearing and the smell was kind of sweet.

What I have noticed though since it's been colder out is that I'm not getting the smell nearly as often. I'm about to chalk it up to evaporation at this point, but maybe I'll mention it when I bring the car in for its second service. I filled the reservoir to the midpoint when it was cold, and then when I looked under the radiator cap, the coolant was full to the bottom of the filler neck.

[wbradley]

A lot of the twins have dripped a tablespoon or two (literally) on the exhaust manifold between oil changes. The 0W20 oil smell was noticeable occasionally but oil loss would not be. I bet thats what you are smelling. You need to shine a light behind the engine on the passenger side where the header connects to the overpipe and look for a bit of burnt oil stain on the exhaust and the slightly oily cover at the rear of the valve head just above it.

[SloS14]

Originally Posted by wbradley

The 0W20 oil smell was noticeable occasionally but oil loss would not be. I bet thats what you are smelling.

oil and coolant smell NOTHING alike. I've never experienced "sweet" smelling burning oil, except maybe at a funnel cake stand at the fair.

[jeepmor]

Just chiming in on this thread to state I noticed some coolant smell recently.

Coolant overflow tank was empty. Last service at 21k, assuming they'd fill it, currently at 27k miles. Coolant level in engine was good, added like a tablespoon or two of antifreeze, showed up in fill spout, good sign. If I'm leaning low or have a slow leak, I caught it early. Might just be running on original OEM fill and never been addressed by dealer, not sure. All dealer service thus far. Been smelling antifreeze for a week or two. No drips in driveway.

Never a temp issue, just keyed on the smell. Filled to max level on overflow tank, now I'll keep an eye on it.

Checked oil fill cap, no signs whatsoever of water in system, will keep tabs on it and chime back in a week or two. If I continue to lose fluid, I'll take to dealer once I'm half way through my gallon of existing blue fluid I just bought.

May be nothing, but I do smell antifreeze on startup once in a while.

[Lonewolf]

Originally Posted by jeepmor

Just chiming in on this thread to state I noticed some coolant smell recently.

Coolant overflow tank was empty. Last service at 21k, assuming they'd fill it, currently at 27k miles. Coolant level in engine was good, added like a tablespoon or two of antifreeze, showed up in fill spout, good sign. If I'm leaning low or have a slow leak, I caught it early. Might just be running on original OEM fill and never been addressed by dealer, not sure. All dealer service thus far. Been smelling antifreeze for a week or two. No drips in driveway.

Never a temp issue, just keyed on the smell. Filled to max level on overflow tank, now I'll keep an eye on it.

Checked oil fill cap, no signs whatsoever of water in system, will keep tabs on it and chime back in a week or two. If I continue to lose fluid, I'll take to dealer once I'm half way through my gallon of existing blue fluid I just bought.

May be nothing, but I do smell antifreeze on startup once in a while.

Have you seen this thread yet? Some interesting stuff in here:

http://www.ft86club.com/forums/showthread.php?t=36150

[Ultramaroon]

Originally Posted by PantsDants

My coolant is below the low line when cold, and about an inch or two above it when hot (~9000 miles on the car). After driving on the freeway for around 15 minutes or so and parking it, I can smell coolant when I get out. It doesn't come through the vents or anything, just outside the car, and the smell quickly goes away.

The very first thing to check with all pressurized cooling systems is that damn radiator cap.



The system relies on the existence of a perfect seal in both the lower seal and the vacuum valve (check valve). If there is even the tiniest, slowest pinhole leak, which is VERY common, there will be localized boiling/simmering in the head even though technically the engine isn't overheating. This is exactly what causes the big swings in coolant level in the reservoir and gradual coolant loss in the form of steam. That's why that little hole exists at the top of the reservoir.

Check/replace the cap. Check the seat inside the neck as well. Make sure there aren't any scratches or pits where the gasket sits.


Please do not let anyone convince you it's ok for this engine to use any coolant. Mine uses none even during the dog days of summer and, yes, I hammer on it.

[sr86]

Ultramaroon is correct, the rad cap is the most neglected part and this part should be checked always 80% of coolant loose is due to a bad or faulty rad cap.