coolant problem

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type53b
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coolant problem

Post by type53b » Sat Dec 23, 2017 12:24 am

Hi guys, the gauge is reading 3/4 when driving, but I don't think it is overheating, I have flushed it, back flushed the whole system. Still read 3/4. One thing I have noticed is the top and bottom rad hoses never get hard( snigger) Even when the car is running for an hour. I have changed the temperature sender (aftermarket) . the resovoir cap is blue only got it a year ago. The fan cuts in and out, she hasn't lost any coolant, I never had to top it up. But I think the system isn't pressurizing. Would this be why she is reading hot? I have plain old water in her at the moment as I took the thermostat out of her to flush her. Have got some prestone coolant to go back in, once I get a new thermostat. Your advice , as always would be most welcome


remember, if it's got tit's or tyre's, sooner or later it's gonna give you trouble.

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Jack92
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Re: coolant problem

Post by Jack92 » Sat Dec 23, 2017 11:27 pm

Hmm not to sure personally, I’ve had a pressure leak issue before which was out of the header tanks cap. Just an idea as I haven’t really got a clue but it might help


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james butler
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Re: coolant problem

Post by james butler » Sun Dec 24, 2017 12:41 am

I've had a few bad new sensors that gave me higher than normal readings.
try changing the thermostat as that regulates the flow of water to the rad via temperature so if its rated too high or just plainly opens too late/is restrictive you will get higher than normal readings.
i would be tempted seeing as you only have water in there to pull the thermostat out completely and see if it makes any difference.
if yes then that will be your problem
other than that take it to a garage and get them to pressure test the coming system to see if theres any leaks although i don't think that will bw your problem
pressurising the system only raises the boiling point of the coolant but doesn't change the fact you could be running hotter than normal in the block


I dont mind project cars but I HATE SANDING!!!

type53b
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Re: coolant problem

Post by type53b » Mon Dec 25, 2017 9:57 pm

James I took the old stat out and flushed/ back flushed the whole system. Some amount of rusty crud came out.I left the stat out and I filled her up with plain old water and let her idle, she still ran up to 105-110, on the gauge but dropped to 70 after short drive. Parked her back on the drive she went back to 105-110 after 10-15 min, fan kicks in for 20- 30 seconds and she drops back to 100. I sat watching her for about 15 minutes and it never varied. I got a new thermostat , Quinton hazell one and tested it and the old one in a pot of boiling water. Both opened at about the same time but the new one opened much wider than the old one.anyway I still think she is not pressurizing cos the top and bottom hoses don't seem to get hard whether the stat was in or out. She hasn't lost any water/coolant. Any advice ??


remember, if it's got tit's or tyre's, sooner or later it's gonna give you trouble.

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unknownmale
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Re: coolant problem

Post by unknownmale » Mon Dec 25, 2017 10:14 pm

Are both the top and bottom hoses hot after running up to temp?

Is there a steady flow of coolant into the tank while running?

After running and you (Carefully) unscrew the cap, can you hear a bleed off of pressure?


- David

type53b
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Re: coolant problem

Post by type53b » Tue Dec 26, 2017 10:52 pm

Both hoses get hot/warm. There is a steady flow of coolant into the tank. There is a tiny bit of pressure when the cap is opened but nothing major.I am gonna tune the carb and strobe light the ignition marks just to check she isn't running lean. I have one of those glass sparkplug gunson things.


remember, if it's got tit's or tyre's, sooner or later it's gonna give you trouble.

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james butler
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Re: coolant problem

Post by james butler » Wed Dec 27, 2017 1:27 am

check the radiator is getting hot and see if theres any cold spots, if there is the rad is blocked in those areas (take the grill off for access).
giving the timing a once over would be a good idea and checking the emissions to see if its running lean.


I dont mind project cars but I HATE SANDING!!!

type53b
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Re: coolant problem

Post by type53b » Wed Dec 27, 2017 1:32 am

OK , I will let you know . many thanks !


remember, if it's got tit's or tyre's, sooner or later it's gonna give you trouble.

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unknownmale
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Re: coolant problem

Post by unknownmale » Thu Dec 28, 2017 10:05 am

Yeah timing and fuel mixture wouldn't be a bad shout to check. Too lean and advanced will run hot.


- David