Does this sound like air in my block?

BUCKEYE COBRA · #1 (**permalink**) 05-17-2005, 02:13 PM

Just finished a intake swap on my 302.

Drained 8 qts from my radiator.
Swaped intake.
Installed new thermo (there was none when I removed my old intake).
Filled radiator untill fluid came out where my temp sender is,installed sender and filled to the top of my reserve tank.
The motor started right up, set timing etc. After 10 minutes my temp guage regestered 240 deg. (I have never seen 200 before).
I'm sure my thermo is installed right. Bottom hose was cool, top hose hot.
Could air in my block cause the thermo not to open?

Thanks,
John

ERA Chas · #2 (**permalink**) 05-17-2005, 03:23 PM

Buck,
Check oil (under valve cover and on dipstick for sickly "mayonnaise" paste.
Intake manifold gasket might have leaked water to intake port causing air pockets in block. Makes the temp gauge read like that. Remove manifold and observe the gaskets. You need some silicone type sealant around the water passages.
Ask me how I know...
Good luck.

BUCKEYE COBRA · #3 (**permalink**) 05-18-2005, 03:08 AM

Chas,
You know because.........
I think I'm in good shape now. I bled some air out through by unscrewing my temp sensor.
All seems OK now. Boy, the temperature is much diff with a thermostat installed.
Thanks for the tip. I'm sure I'll be doing this again (as I dig deeper in for QUEST....)
John

Ron61 · #4 (**permalink**) 05-18-2005, 07:32 AM

John,

Just a suggestion if you haven't already did it. Many of the people drill holes around the thermostat lip and that lets a little water flow until it is warm enough for the thermostat to open.

Ron

BUCKEYE COBRA · #5 (**permalink**) 05-18-2005, 07:37 PM

Ron,
Thanks for the tip. The next time I have it out it will get drilled.....
John

427sharpe · #6 (**permalink**) 05-18-2005, 07:47 PM

A useful tool for a Cobra owner is made by KDT tools, I think a part number 9145. It is a hand held air gun, powered by shop air, that will pull the entire cooling system down to a vacuum is about 30 secs - 1 min. A sure way to eliminate all air pockets from the system for filling. It runs about $85, and NO, I don't sell them.

Scott S · #7 (**permalink**) 05-18-2005, 09:37 PM

About a 1/8" hole is all you need, and place it at the top of the thermostat. Make sure no gasket sealer gets in it.

Scott S