Where the heck is the coolant going?!

[Mbrooks420]

The hose is probably clogged. Pull it off the radiator and blow it out.

 

[Beachcomber86]

The hose is probably clogged. Pull it off the radiator and blow it out.

I'm going to be stupid here. How can the hose be clogged if it is blowing coolant out of the overflow? I know it's not clogged because when I start to open the cap, I'll get air bubbles from the radiator into the overflow.

 

[Mbrooks420]

Sometimes junk can get built up in the bottom of the tank, and the radiator can push fluid into it under pressure, and when it cools it sucks the sediment back into the skinny hose and blocks it. Probably not the situation in your case. Still have the old cap? Yours might be bad.

 

[Beachcomber86]

I do have the old cap. If I don't find a leak, I'll put it back on and see if it gets better.

I had to replace the overflow hose a couple months ago. I pulled the tank and washed it out, so I'm pretty sure it's not plugged. Maybe it's leaking at the rear. That is my check for tonight!

 

[boominXplorer]

If your leaking a decent amount of coolant then there will be too much air in the system for the radiator to pull in coolant from the overflow.

 

[Beachcomber86]

Well, spent 20 minutes with the beast and not a leak to be found. Held it at 2000 rpm for 2-3 minutes with the radiator cap off and on ramps to try to get all the air out of the system. Ran front and rear heat at maximum. 10 plus minutes at idle and 2000 rpm with the cap on.

Rear hoses. Look their age, but no white residue or any glistening.

Y connector - no leaks

Thermostat - no leaks

Heater hoses - no leaks

Guess I'll rent the pressure tester next.

 

[rasouth]

I had a similar problem on my '96. I had a small pin hole in the top portion of my radiator and steam would escape while driving. No coolant was seen dripping down and no puddle. Overflow tank was always half full.
Another problem I have now is that the intake manifold gasket has cracked and is slowly letting water into the pistons. At first I had no signs of leakage or misfiring, maybe a little water out the exhaust pipe at start up, but once it warmed up no water, no steam. A friend of mine was looking at the engine when I revved it up and he noticed coolant leaking down side of engine but only under load.

 

[Beachcomber86]

I'm on the 3rd radiator, so hopefully it isn't that!

 

[Beachcomber86]

Pressure test completed.
1. Pressurized to 20 psi and held for 15 minutes - less than 0.5 psi drop
- did not see or hear any leaks

2. Depressurized system, started engine and let idle/rev for 12 minutes
- system pressure slowly came up and maxed at 17.5 psi
- pressure dropped when engine was revved above 2000 rpm
- held RPMs at or above 2000 rpm for more than 2 minutes

3. Shut down engine with system pressure at 17.5 psi
- held for 5 minutes, less than 0.5 psi pressure drop

Any guesses as to what to do next?

 

[07EddyB]

There is only one component in your cooling system that adjusts pressure.

 

[Beachcomber86]

There is only one component in your cooling system that adjusts pressure.

And.......

 

[07EddyB]

And.......

Ignore me. For some reason I was thinking pressure issue when your thread clearly state coolant loss

Not sure why the pressure would drop at 2000 though.

 

[Mbrooks420]

It must be leaking at higher RPM. I had a Skylark that had a head gasket leak that only leaked above 3,000. I replaced the water pump and thermostat and let it run in the driveway for 2 hours and it didn’t overheat like it did while driving. First drive, it overheated. Had someone stand on it while I looked under the hood, and the head gasket was pissing out right onto the manifold and burnzing off

 

[Beachcomber86]

Ok, I can accept that it probably is a head gasket issue. I've tried a head gasket sealer in the past with marginal improvement.

So, the question is....Do I let this ride til the timing chain eventually craps out then just swap the motor? or Do I work on the head gasket (which means pay someone to work on the head gasket)

Other than this, she purrs like a kitten.

No, it doesn't overheat.

 

[gdgiordano]

Ok, I can accept that it probably is a head gasket issue. I've tried a head gasket sealer in the past with marginal improvement.

So, the question is....Do I let this ride til the timing chain eventually craps out then just swap the motor? or Do I work on the head gasket (which means pay someone to work on the head gasket)

Other than this, she purrs like a kitten.

No, it doesn't overheat.

If it has more than 175k on it you should rebuild it and upgrade it while you are at it!

 

[boominXplorer]

Ride it till you have a real issue. Its not worth tearing it apart on an educated guess in my opinion. Then put a low mile used motor in it with a bunch of new parts. In my experience internal coolant leaks can be a pain to find/cure.

 

[Mbrooks420]

Dump in a bottle of K seal, and ride it out.

 

[Beachcomber86]

I've tried K & W Chemical FiberLock® Head Gasket & Block Repair

Is K seal better?

 

[Mbrooks420]

You’ve tried it on this motor? K Seal is supposed to be the best.

 

[Beachcomber86]

You’ve tried it on this motor? K Seal is supposed to be the best.

I've not tried K Seal.