FJ40 anti-freeze odor mystery...

[Brian in Oregon]

I've been getting a faint anti-freeze odor in my FJ40 ever since I got it a few years back. Not a big deal, but it's gotten stronger lately.

It's particularly strong when the front heater fan is turned off, or is on low. When on high, the odor is faint or not there at all. Sniffing around the front heater was negative for anti-freeze smell.

The rear heater does not smell of anti-freeze.

Using the vents makes no difference.

The radiator slowly loses coolant level, taking a few months to go down a quart or two. Installed a new radiator cap, and later added a coolant recovery bottle. Not much coolant is ever caught by it, even with a full system.

I'm suspicious of the heater core, but, I can't pinpoint it to the core.

Any suggestions?

 

[CruisinMT]

my 67' does the same thing. Everything seems to work fine so I don't worry about it, though I have replaced my front heater core.

 

[Josie'sLandCruiser]

Hi All:

I have noticed coolant-smelling "steam" coming from the heater core on my rig when the heater is being used. While I had the heater out a few years ago I flushed out the core with muratic acid to clean-out 30 years worth of crud and scaling. I assuming there is a pinhole leak or two now.

If you really use the heater in your 40 Series a lot you might consider just replacing the stock heater with a new "Mohave" unit.

Regards,

Alan

 

[1979fj40]

Ive seen the cores on ebay for about $90. Seems high to me, I,d pull it and take it to a radiatror shop and let them try to fix it first.

 

[IDave]

It's pretty easy to see coolant green on a core if that's it. You just have to look.

I smelled the pinhole leak in my front heater intermittently long before I broke down, looked at it, took it out and had it re-cored. It never dribbled outside the heater.

 

[Blue77FJ40]

I've also noted a coolant odor in mine since I bought it. I never found any leaks, but am convinced it's coming from the heater. Did the odor go away for those that had them recored?

What's a "Mohave" unit?

 

[IDave]

I've also noted a coolant odor in mine since I bought it. I never found any leaks, but am convinced it's coming from the heater. Did the odor go away for those that had them recored?

Yes, absolutely for me. All I ever saw was a tiny dried droplet of coolant in a crease along one edge of the core.

 

[Brian in Oregon]

What gets me is - why does the odor go away when the heater is running full blast? It's strongest when turned off and less when on low. I'd think running on full blast would give the strongest odor?

 

[zglad]

I've had some luck in other vehicles adding some ultra violet die in the radiator, driving it for a week or so, then looking with a black light to see what glows. I found a small intake mainfold leak that way. I don't know if it will work for you. The local parts house had the die. Good luck, those issues drive me crazy.

zglad

 

[Kroll]

I had the same issue in my 72.
I would notice a faint drop of coolant on my transmission hump whenever the temps dipped below -18C.
When my dad would drive with me, with his super senses; he noticed "coolant mist" in the cabin.
Got it cleaned and pressure checked at a rad shop, and no problems since them!

 

[IDave]

What gets me is - why does the odor go away when the heater is running full blast? It's strongest when turned off and less when on low. I'd think running on full blast would give the strongest odor?

All I can think is that the air blowing through the core dilutes the odor enough to make it undetectable. The same thing happened to me.

 

[bsmith123]

leak

Could be that the leak is so slow that on high you are drying it up as fast as it happens

or it could be accumulating all night and drying out as you drive and putting it on high just dries it faster

the smell from the front plus the coolant leak pretty much sums it up though

easy job

you could have a look it may be as simple as a little soldering and putting it back in

 

[folsom50]

You can pick up a new heater core through Rockauto for $70-80. Mine was slugged with "silver seal" and had a tiny pin hole in it. I swapped it out and no more smell, and heat when I want it.

 

[Josie'sLandCruiser]

Hi All:

A "Mohave" (Mojave, actually) heater is an aftermarket replacement heater.

See here:

Flex-a-lite Mojave Heaters - summitracing.com

Regards,

Alan

-----------------------------------------------------

<snip>

What's a "Mohave" unit?