Where does my coolant go? (1 Viewer)

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

boombapslappy

boombapslappy

Joined
Aug 3, 2007
Threads
84
Messages
1,921
Location
South Carolina
'89 FJ62 with 160k miles, stock everything except lift.

I notice no leaks around the radiator. Hoses seem to be snug and are not brittle. Oil is clean and clear on the dipstick (on the driveway is a different story). Coolant in the radiator is clean and clear and always seems to keep it's level. I've had to top off the resovoir several times in the past week. What gives? The resovoir doesn't appear to be cracked but I have not removed it to inspect and it did not leak after topping it off last night (I watched for a while). Could the radiator be leaking and it evaporates away before I notice it? If this were the case, I guess I wouldn't notice the same level at the rad. cap. Any help is appreciated. I have no idea where to go from here.

ps: sorry to add to the radiator threads but I didn't read anything in any of them (that I found) that seemed to match my story.
 
did you change the fluid lately?

I would think if you didn't burp it enough they may cause the level to appear higher then as you drive it would burp itself and the air that was in the engine would be less, and making you water level lower.
 
Bought it in Sept. and changed all fluids the first week of Oct. I read all the threads about burping the system and I'm pretty sure I did it correctly. Everything was great until a couple of weeks ago.

External options (which I don't see but could still exist): hoses/resovoir/radiator, anything else?

Internal Options: a blown head gasket would allow it into the crank case where I would notice milky oil, I could do a compression test--that would point me in a direction would it not? anything else? With these options would I not notice something while driving? Rough idle, weird noises?
 
Last edited:
check underneath your front carpets. Mine seemed dry at the top but wet at the bottom.
 
Head gasket can also let coolant into the combustion chamber where it leaves with the exhaust.

smkymntn said:
check underneath your front carpets. Mine seemed dry at the top but wet at the bottom.
Click to expand...

Do you smell antifreeze from the cab? That was the first sign my heater core was going. Mine never soaked the carpet, leaked just enough to keep the heater box wet and fog up my windows on a cold day.

Butt
 
Thanks Adam. Hadn't thought of that. I don't smell it inside but when I installed the lift, I noticed something weird around the rear heater. Could be leaking there?
 
Just checked inside. Nothing is wet. No smell of coolant. I don't want to say it, but it must be going out the exaust. Where does that path take me?
 
More likely that it wasn't completely full. Now the expansion is burping the air out and the resevoir is replenishing that space. I recently had the opposite occur, in that I filled it too completely and as it expanded it filled the resevoir then pissed out the little resevoir drain hose. Maybe you should raise the passenger side front tire (drive up onto a rock or something) get a funnel that wedges into the lower part of the filler neck, fill the funnel to have a resevoir of fluid that is above the engine level, start it up, turn on both heaters and let it get to operating temp and keep that fluid level full in the funnel, let it run for about 10 minutes. You will then know that it is absolutely full. Then if it pisses out the resevoir drain a bit the next couple times you shut it down, you will know you are maximized. At that point, if it's still eating fluid, then check the more expensive problems.
 
It could be that your system is only leaking when it is hot (and pressurized) and that's why you don't notice a leak. If the problem persists you should do a pressure check of the system. You can use a pump device that will pressurize the cooling system. A black-light can then be used to find coolant leaks. Your local mechanic should be able to do this for you.
 
My rear heater hoses leaked but only when hot and under pressure. There was never a puddle under the truck. Check the entire rear heater lines and look for signs for leaking.
 
slcfj62 said:
If it is a head gasket and leaking into the combustion chamber, the tell-tale sign is white exhaust smoke.
Click to expand...

There's no white smoke but everything else seems to be leaning this direction. It could also be the rear heater though. I'll have the system pressure checked.
 
Lewy said:
My rear heater hoses leaked but only when hot and under pressure. There was never a puddle under the truck. Check the entire rear heater lines and look for signs for leaking.
Click to expand...

The hoses and hard lines for the rear heater run under the truck on a 62. With all the road junk and possibley salt being slung up there you could have a small hole/leak. I had a similar issue that finally surfaced when I started getting a puddle of coolant on the drive way. Replaced the hoses and hard lines and the coolant level issue went away. FWIW
 
If it is a head gasket bleeding into the combustion chamber or exhaust valve ports you can check it cheaply by getting some test strips from your auto suppy store. You run the engine warm open the radiator cap and hold one over the cap...if exhaust gases are venting out the radiator these test strips will detect it by changing color before you see white smoke out the exhaust pipe or choclate milk colored oil. They react to exhaust gases and are fairly reliable from my expereince. A cracked cylinder head appears exactly like a blown head gasket depending on how big the crack is. I know this from experience...not theory. You can also disconnect the heater hoses and block them off and drive it to see if any coolant ends up MIA. That will at least isolate the issue to one or the other before you go tearing things apart. Good luck!!
 
Sneaky Leaky

I was fighting with this same problem recently when I "Busted" the culprit one day while it was in the drive way. The hoses on the outside appear fine but they deteriorated(SP) from the inside. So in affect when my FJ62 would come up to temperature it would actually blow out around the hard line pieces from the rubber ones. When I took the rubber ones by the thermostat off the interior of the hose was all crumbly and the outside looked perfectly fine (a little distended" due to age but nothing out of the ordinary. Not sure if this is your ptoblem or not but I went through all of exactly the same symptoms and troubleshooting and this ended up being what was wrong with mine.
 
mikailio said:
The hoses on the outside appear fine but they deteriorated(SP) from the inside.
Click to expand...

We have a winner!! :clap:

Replaced all hoses and we're doing great so far!
 
You must log in or register to reply here.

Similar threads

D
Where does this hose go?
Replies
2
Views
573
dsagona
D
BelgianHJ60
Where does this part belong?
Replies
3
Views
479
mongoose2231
mongoose2231
RevISK
Where does this hose go?
Replies
19
Views
1K
RevISK
RevISK
chris777
Where can I find wheels that fit my 60?
Replies
3
Views
479
chris777
chris777

Users who are viewing this thread

Total: 2 (members: 0, guests: 2)

Share this page

Back
Top Bottom