Radiator Pressure

[BigDave LM6174]

My 52 Henry J 6 cylinder has got me baffled.  After running it, I turn it off, and the relief tube starts dripping from radiator.  I have flushed radiator, replaced cap with new 4 psi cap, and still drips after a good ride.  Suggestions?  No sign of bad head gasket.  Oil level is same.  Running 50% antifreeze and 50% distilled water.   Thoughts ? suggestions ?

[alohagreen]

mine wants to run ( NOT FULL ) to the top...
it spits it out, till it finds its own HAPPY place...
i  know not much help, just telling you what mine does...

 

[boatingbill]

When you drive it, does it run at normal temperature ? That tells a lot.

[Terry T]

both of my 6's spit some out if it is filled to the top

[Fid]

When I fill mine, they always spit for a day or two and eventually stop. They've never overheated.

[MarkH]

Starting from a cold full tank, heat expansion is going to make it drip as the engine warms up. Engine block coolant temp builds slightly once you shut off the fan & water pump, so even if you hit a volume/temp "equilibrium" with the engine running, you'll always get that extra bit of shutdown expansion when you shut down if you keep topping it up cold, and there'll always be an air space in the (cold) tank if you don't.

Coolant recovery tanks eliminated all that.

[BigDave LM6174]

I am running normal temperature while driving, not overheating from what I see.  However I am seeing bubbles when car is running and have radiator cap off.  Could that be combustion coming through system from bad head gasket? I did use Preston radiator flush yesterday, then flushed system real good with clean water. Thinking maybe bubbles are residual from the flush stuff?
I guess I will let it spit for few days and recheck it. 
I am hoping I just overfilled it but the bubbles have me concerned.

[BigDave LM6174]

Would the distilled water make any difference?  We are in drought so water is scarce out here in California. 

[retired wrench]

 
   I have used distilled water with no side affects. If your bubbles are sporadic that's one thing if they are a steady stream that's worrysome.

[BigDave LM6174]

Talking to a mechanic friend today at lunch, he thinks I simply have air in the system and that I need to simply run the car with it pointed up hill (Front end up) so the air rises from the block to the Radiator.   Any of you hear of this?

[alohagreen]

Talking to a mechanic friend today at lunch, he thinks I simply have air in the system and that I need to simply run the car with it pointed up hill (Front end up) so the air rises from the block to the Radiator.   Any of you hear of this?

yes pointing up is
old skool ... 

[BigDave LM6174]

I took the HJ to the radiator shop because it is still spitting out the tube.  We were able to confirm that no exhaust gas is in the system, and my head gasket appears good.  He thinks I simply had the radiator overfilled.
The coolant now seems pretty low to me for where he lowered it, however the car is not overheating and no longer spitting.  IT is in the 80's here in Los Angeles despite being in the middle of El Nino.
Can someone do me a favor, and look in your radiator with a measuring tape, and give me the measurement from the top of fill where the cap goes to where the coolant is when it is cold?  Just seems too low for what I would think is correct.

[alohagreen]

DEAD cold mine just covers the fins
that is while LQQKing in with the rad cap OFF.
mine has NEVER over heated on  HOT days.

 

[BigDave LM6174]

Mine is lower then that. 

[MarkH]

I can't remember ever having any radiator normally run below the fins. I also can't imagine a solid volume of water expanding that much and coming out the overflow.
You're not over heating which is good, at least not anywhere near the temp sender. I can't help but think you've got an air pocket somewhere. Even a small pocket of steam could account for a lot of expansion that vanishes at cool down.
My wife's 4cyl Saturn was vexing the living sh** out of me earlier this winter because I couldn't get the heater to put out anything but tepid air. The thermostat is in a bastard location so I paid the shop for that, no better. Finally searched Saturn threads and found it's a common problem and I needed to "burp" the system. Took a couple tries but finally got the air out and the heater will melt ice off the windshield again.
My sucessful attempt was cap off, topped full, fast idle for about 15 minutes after reaching full operating temp

A steep hill probably wouldn't hurt either