NC29 half empty radiator. HELP !

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PTsakthi
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NC29 half empty radiator. HELP !

Post by PTsakthi » Sun Mar 18, 2018 9:45 am

i have been having issues of coolant loss. recently after riding the bike, i would let the bike cool down than check the coolant level at the radiator.
And i have noticed the radiator is always half empty. right after stopping the the bike, the overflow bottle would be almost full (just below the neck). After the bike cools down, Overflow bottle will be filled to upper level, and radiator will be half empty. I would top it off with water at the radiator, and repeat the same thing, riding it, than checking it again. Same results, half empty again.

When i looked inside the overflow bottle while the engine is running, i can see constant bubbles when the engine is running,
this happens before topping off the radiator.

The bike seems to run perfectly fine, no over heating or anything, fan turns on and everything. Checked for visible
leaks, nothing. Checked engine oil, seems fine, constant level and color. Changed radiator cap as well (1.1Bar rating)

Any and all suggestion will be greatly appreciated

Thanks,
PT

(ps: this is my first post here)

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Re: NC29 half empty radiator. HELP !

Post by Suzuki416 » Sun Mar 18, 2018 10:06 am

if you are filling it at all then you are losing it somewhere.

You need to get it checked to see if you have hydrocarbons in your coolant.

Gut feel - leaky head gasket..

Also do a cylinder compression test.

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Re: NC29 half empty radiator. HELP !

Post by PTsakthi » Mon Mar 19, 2018 12:22 am

Where I am from, workshop/Mechanics don’t do HC test, or compression test. They tell you what they think is wrong based on experience and expect you to trust them. In my experience they are wrong most of the time.
I’ve already ordered a HC test kit and waiting for it to arrive.

BUT, I strongly feel it’s not the head gasket, is there anyway air could be forced into the system ? Which in turn, forces fluid to drain out ?


I had problems with leaky hoses, which I thought was the reason behind the coolant loss. I’ve already replaced them. (The issues I am facing happened after changing the hoses and checking)

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Re: NC29 half empty radiator. HELP !

Post by LITTLE=ONE » Mon Mar 19, 2018 3:46 am

Hello

On my car , when it was blowing a constant stream of bubbles into the headed tank , it was the head gasket that was at fault , your symptoms sound the same.

My guess is your head gasket is leaking from the combustion chamber to the cooling jacket

Is white smoke coming out of the exhauste when the engine is ticking over , and it clears when revved .

Little=one

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Re: NC29 half empty radiator. HELP !

Post by PTsakthi » Mon Mar 19, 2018 4:32 am

That’s the thing, there isn’t any white smoke!
Did you notice any white smoke from your car ?

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Re: NC29 half empty radiator. HELP !

Post by LITTLE=ONE » Mon Mar 19, 2018 5:24 am

My car chuffed white smoke like a train

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Re: NC29 half empty radiator. HELP !

Post by PTsakthi » Mon Mar 19, 2018 1:12 pm

Something weird happened today. The radiator was only half full like i mentioned, i decided to take a short 20min ride without filling it up. It ran fine, parked it,and waited for it too cool down. than when i checked the radiator this time around, the coolant was higher than what i remembered, about 1-2inches below the neck. Unlike, what i saw before riding it, which was only half.

Am i missing something ? could there be that much air in the system or something ? :?:

Thanks for the feedback

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Re: NC29 half empty radiator. HELP !

Post by dunkenb » Mon Mar 19, 2018 1:22 pm

Maybe a leak under pressure. Check the connectors under the tank by the left of the carbs . The plastic joiners can become brittle and so can the narrow pipes.
Also maybe the radiator cap needs replacing?

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Re: NC29 half empty radiator. HELP !

Post by Davez29 » Tue Mar 20, 2018 1:53 pm

Sounds like a airlock or no pressure in the system, but also very odd if no leaks or white smoke, only way to find out is to do a coolant change. Easy to do and just as fast as waiting for a reply here. Also as dunkenb mentioned, maybe renew your rad cap and check the condition of your coolant pipes as I suppose they could be too soft and like old fuel pipes could narrow and might create a vacuum. maybe stick a hose pipe down the rad and flush the system before adding coolant. Check your oil as well for any contamination.

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Re: NC29 half empty radiator. HELP !

Post by cbr400rrn » Tue Mar 20, 2018 11:17 pm

PTsakthi wrote:
Sun Mar 18, 2018 9:45 am
i have been having issues of coolant loss. recently after riding the bike, i would let the bike cool down than check the coolant level at the radiator.
And i have noticed the radiator is always half empty. right after stopping the the bike, the overflow bottle would be almost full (just below the neck). After the bike cools down, Overflow bottle will be filled to upper level, and radiator will be half empty. I would top it off with water at the radiator, and repeat the same thing, riding it, than checking it again. Same results, half empty again.

When i looked inside the overflow bottle while the engine is running, i can see constant bubbles when the engine is running,
this happens before topping off the radiator.

The bike seems to run perfectly fine, no over heating or anything, fan turns on and everything. Checked for visible
leaks, nothing. Checked engine oil, seems fine, constant level and color. Changed radiator cap as well (1.1Bar rating)

Any and all suggestion will be greatly appreciated

Thanks,
PT

(ps: this is my first post here)
Any more news on the level? Are you still having problems


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