Idle temp
 

Took my '31 out the other day just up the road to put balloons on the corner for our family reunion. While tying the balloons I left the car idling and on the way back to the house had some coolant spitting out from under the rad cap and when I got home (only 1.5 miles) it was steaming pretty good out the cap. It has a new motometer and it was just starting to register (came up about 1/4"). The water pump is new and pumps well, no thermostat. Was it just finding it's level (I DID have it right full) or does it sound like I have a cooling problem?. Can the motometer be trusted or is it too inaccurate to be of any practical use?. BTW, I don't run straight water, I run antifreeze.

Re: Idle temp
 

First of all the radiator cap should not leak,the radiator will never stay full to the top it will seek it's own level.The coolant temp would have to checked with a thermometer to verify an overheating condition,antifreeze is usually a 50,50, mix.

Re: Idle temp
 

steam and spitting ( if any )should be out of overflow only ... check overflow pipe is clear ( use airline to blow through it)....Try another rad cap for a better seal.... don't believe any motormeter ( many don't reach the radwater anyway)... don't fill rad above the level baffle when topping up ( about 1 1/2 inches below neck).... ensure ignition timing about right..... after these simple things if still concerned consider flushing rad, and re-torqueing head ... before delving deeper
I nice sometimes helpful visual aid can be made by adding a piece of neoprene tubing to the outlet of the overflow pipe and run it up into your line of vision by the outside of the hood ( direct boiling water away from wife in passenger seat tho!)

Re: Idle temp
 

sorry duplicate post!

Re: Idle temp
 

Stock model A is very good at eliminating excess coolant and engine oil----most like the coolant level just below the radiator baffle, and the engine oil level below the F

Re: Idle temp
 

By the time that it finds it's level and spits out the rest, the temp bulb will be above the coolant and will be very slow to show the temp. Might eventually catch up to show the real temp. They are dependable only if nothing is wrong. will set off an alarm after it is too late. Steam will be hot but does not conduct like the denser liquid coolant.

Re: Idle temp
 

That two parts of the OP that would concern me is: #1 seal the cap #2 spitting water is one thing, shouldn't be steaming.

Re: Idle temp
 

I would make sure that your radiator cap seals well like others have noted. You may need to add a thicker gasket or add a home cut gasket made from an old inner tube or similar material to your existing gasket. It should not leak from the cap regardless if hot or not.
Get a cheap dial meat thermometer and use it to check your coolant temperature so you know for sure what it is.
Did you happen to have the engine retarded while you were putting out the balloons?

Re: Idle temp
 

Retorque the head before you do anything.
If you are making steam, your radiator is plugged. Try all the band aids and you will finally get a new radiator. Happens to all of us.

Re: Idle temp
 

Steaming and spitting are different things. Check in detail what you observed really. Finding the right filling level usually takes place WITHOUT steaming. My level is some mm below baffle, anything above will be thrown out after 20-30 mls, but definitvely not within 1 1/2 mls.

Re: Idle temp
 

i was overheating, boiling, steaming and so on with a used radiator i had bought. there is only one radiator shop near where i live and they have a questionable reputation so i decided to try it myself. i ran across a you tube video on "redneck " radiator cleaning and thought that's me. i have done my own plumbing for years and am well aquainted with soldering. i spent the better part of a day removing the top tank, rodding and flushing the tubes until i got good flow. you wouldn't believe the crud that washed out.( i can imagine someone dipping creek water to fill the radiator, leaves tadpoles etc.) i resoldered the tank using radiator solder and liquid flux. i've now got an engine that doesn't overheat.

Re: Idle temp
 

Check engine and radiator temperatures w/an infared to know where they're actually at.

Re: Idle temp
 

Just me, I would flush the radiator with vinegar. I did and could not believe the stuff that came out.
There is a youtube description on how it is done, very helpful.


Gerry Birch Bay WA

Re: Idle temp
 

Larry, you did something that few people could do. No one wants to take that top tank off. Since you were successful, you should offer to do it for others. Work up your price and I bet you would save a lot of old cores out there. All of the old cores need to be rodded out.

Re: Idle temp
 

RE; ( many don't reach the radwater anyway) Motometers DO NOT measure water temp, they measure the temp above the water. Then were never made to be submerged to get a reading.

Re: Idle temp
 

Thank you for all the feedback. Appreciated.