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Removing Cooling System Bubble

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noutlaw

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I believe I have a bubble in my cooling system. It was nice enough on sat to take the car for a drive. (68F/Sunny - colorado). When driving, car was running @ normal temps, however when I slowed down/stopped the temp would run up (220-230) almost immediately, start going again and it goes right back down...

My suspicion is a bubble because there's no way the water was going from 180 to 230 in 20-40 seconds...

Anyway - I wasn't sure if there was a higher level bleed (heater?) that i could use to see if there is in fact some air in the system and more importantly how to remove it...
 
Noutlaw, has the cooling system been serviced ; radiator boiled out and rodded,pump in good condition, block been flushed out recently and is the fan belt adjusted properly. Overheating as you described is typical of some Healey stock cooling systems.---Keoke
 
I think flushing the system would be a good idea if you haven't done that in the last few years. There could be alot of rust/sludge in the water passages of the block. First, though take your car to a recommended radiator shop. They will have an infared sensor to determine if the radiator is cooling properly. They may also have better flushes than you can buy at auto zone. Removing the Healey radiator is not difficult, should that be recommended for rodding/flushing.
But, it is not unusual for the temp to go up when you shut off the engine, although from your readings, yours is higher than normal,and it shoudn't shoot up that high just slowing down, unless the fan belt is loose and not turning the water pump properly or the w/p is bad. Remember that the temp sensor is in the engine block. Once the car is shut off, so goes the water pump, and the coolant in the engine heats up rapidly because it is stuck there, surrounded by hot metal. Your running temp seems normal, but I think when the car is shut off, the temp shouldn't go up more than about 20 degrees.
 
What kind of fan do you have? You may want to upgrade to a better fan If you are using the stock fan. What model is your car? I know a bn7 had a fan that wasn't all it should be. Bob
 
BOB, I know a whole bunch of Healeys that had fans that weren't what they should be.---Keoke- /ubbthreads/images/graemlins/laugh.gif /ubbthreads/images/graemlins/angel.gif
 
Before going too far it might be wise to invest a few dollars in a candy thermometer and verify that the temperature guage readings are accurate. Perhaps the fan is mounted backwards?
 
Hey guys thanks for all the input - I've been off line a couple of days...The car is "brand new" completely rebuilt - BJ8 and a 6 bladed fiberglass fan.

So the system is clean, new radiator core, hoses, etc.

What it appears to be is that the thermostat is sticking... I went for another drive and it was running fine - came to a full stop and temp held fine - then drove some more and came to a stop and suprise it started going up... drove around in 2nd (15 mph) and it was going up... so shut it down all together...

The benefits of working out "new car" kinks.
Guy who rebuilt car is Knut Holzer of British Motor Corp in Phila, PA. (if you look on harwood-enterprises, there is a recently sold golden beige car 1967 3000) that was done by Knut as well.
 
Don't sound like thermostat sticking to me Noutlaw. Why not call the guru and see what he thinks??.---Keoke /ubbthreads/images/graemlins/yesnod.gif
 
Re: Removing Cooling System Bubble --- Keoke..

Keoke - (just for closing the loop)..

Turns out it was a faulty gauge on the car... did digital thermostat on the engine and it's running fine. Getting new replacement... /ubbthreads/images/graemlins/smile.gif

Thanks for the input.
 
Re: Removing Cooling System Bubble --- Keoke..

/ubbthreads/images/graemlins/thumbsup.gif----Keoke
 
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