You don’t stop riding because you’re getting old, but you get old when you stop riding.

Cooling system

Share
avatar
Fair Weather Rider
the 800
the 800

Posts : 256
Location : Tenbury Wells

Cooling system

Post by Fair Weather Rider on Fri 26 Jan 2018, 3:18 pm

Trying to sort my cooling system before Summer.
Last year on very hot days, in traffic, with the fan switched on manually I was overheating.
Once out of the traffic and on open roads no problem.
Took my thermostat out today and dunked it in a jar of boiling water and it opened, so that seems Ok.
Put it all back together and ran engine almost to red on gauge and Fan did not cut in ( I purposely didn't switch it on Manually so as to see if it worked automatically) The bike blew water out of the little expansion tank, then I stopped the engine and could hear the water boiling. I have a spare thermostatic Rad switch witch I will try tomorrow.
Thinking about a new thermostat, but don't want to spend unnecessary money.
My questions are: where on the temp gauge is the fan supposed to cut in?
How far should the thermostat open?
Shall I take thermostat out altogether?

Would appreciate comments, thanks.
avatar
davecb5002
Laser Shark
Laser Shark

Posts : 191
Location : OSWESTRY SHROPSHIRE

Re: Cooling system

Post by davecb5002 on Fri 26 Jan 2018, 7:43 pm

Have you got a seperate switch for your fan then ?? Not rely on thermostatic fan switch to kick in ??
I have a spare thermostatic fan switch and rad thermostat if you should need one.
avatar
Jameshambleton
Moderator
Moderator

Posts : 2694
Location : Bedale, North Yorkshire

Re: Cooling system

Post by Jameshambleton on Sat 27 Jan 2018, 7:09 am

You need a replacement thermoswitch, which is fitted to the rad. The thermo switch is a heat switched ground.

There are 3 separate parts to the cooling system, the thermoswitch (which turns on the fan using a switched ground based on restanance), the thermostat (which restricts the coolant flow to keep the engine running at an optimal temp), the thermo sensor ( this is also a resistance based heat which gives the the temp shown on your temp gauge on the clocks) .
avatar
geoffnorfolk
Barry Sheene
Barry Sheene

Posts : 70

Re: Cooling system

Post by geoffnorfolk on Sat 27 Jan 2018, 8:57 am

There's really one more part to the cooling system which might be worth considering.   Could be wrong here but the water shouldn't be coming out of the expansion tank........ if it's overheating, it should come out of a small "rubber" pipe underneath the bike (comes from by the radiator cap)..... it certainly does on my ntv650 so presume they're the same. It suggests to me that the radiator cap is faulty and not sealing properly ..... this would allow the water to "boil" at a lower temperature and affect the cooling system significantly.  The fan switch might be faulty as well  of course and this can be tested with hot water and a multi meter.
avatar
Fair Weather Rider
the 800
the 800

Posts : 256
Location : Tenbury Wells

Re: Cooling system

Post by Fair Weather Rider on Sat 27 Jan 2018, 9:35 am

Thank Guys. I tried a second rad cap, made no difference, going to change the rad thermo switch today.
Will keep you all posted.
avatar
geoffnorfolk
Barry Sheene
Barry Sheene

Posts : 70

Re: Cooling system

Post by geoffnorfolk on Sat 27 Jan 2018, 10:10 am

Does seem like the bike's overheating though in traffic.. even when you've manually switched the fan on.  Might be worth flushing the radiator through using a hose....reverse direction from the normal flow... haven't used the stuff but seem to remember there's something you can buy which will help clear any junk in the rad. Are the "fins" in the rad blocked with general "crud"? On my NTV forum, have heard of the pump being badly corroded so the impellers aren't functioning well..... this might be a last resort! 

Regarding the thermoswitch...... only going on my ntv here (its my son that has the cb500 in case you wonder why I'm here!!)
It might be worth checking the actual connections/wire to the therm switch before replacing it. With the ignition on, Take the wire that goes to the switch and press it
against the engine.... the fan should come on..... if it doesn't, there's a fault in the wiring to the switch.  If it does, then press it against the actual radiator where there's exposed metal..... the surround of the thermoswitch works well. If the fan  now doesn't come on..... there's a fault with the earth wire connectoin  that goes onto the back of radiator..... this can become badly corroded and cease to function.  I'm only going on an NTV650 here so the cb500 might be different.
If fans still not working, then try the switch... they're very expensive so I'd try the first "tests" before you  splash out.
avatar
Fair Weather Rider
the 800
the 800

Posts : 256
Location : Tenbury Wells

Re: Cooling system

Post by Fair Weather Rider on Sat 27 Jan 2018, 11:27 am

Going to check all electrics today and make sure Fan has a good connection to back of rad.
Had thought of water pump impeller, may have a look at that today as well, I have a spare engine which I can take the water pump off, will also take Rad off, have a spare one of those as well.
Do you sometimes wish you hadn't started something? Still it has to be sorted.
I have had 2 Deauville's nice bike's but a bit on the heavy side for me, I find the CB very manageable.
Happy days. (Bootiful) Very Happy
avatar
Fair Weather Rider
the 800
the 800

Posts : 256
Location : Tenbury Wells

Re: Cooling system

Post by Fair Weather Rider on Sat 27 Jan 2018, 2:45 pm

Removed Radiator and Fan fell off, brackets rusted through. Have ordered new Rad and Fan off eBay £140.00 Fed up codging and bodging. (wife will go ballistic)
Removed and stripped Water Pump, Impeller all Ok, refitted, (had to take left crash bar off to draw pump out)
Tried to check Thermo switch in Boiling water with Multi Meter did not get a continuity, so assuming it is Fu***d.
1445hrs now have pushed bike back in shed, have had enough for today.  Very Happy
avatar
Fair Weather Rider
the 800
the 800

Posts : 256
Location : Tenbury Wells

Re: Cooling system

Post by Fair Weather Rider on Sat 27 Jan 2018, 2:50 pm

@davecb5002 wrote:Have you got a seperate switch for your fan then ?? Not rely on thermostatic fan switch to kick in ??
I have a spare thermostatic fan switch and rad thermostat if you should need one.

Have PM'd you Dave about Thermo fan Switch.
avatar
Fair Weather Rider
the 800
the 800

Posts : 256
Location : Tenbury Wells

Re: Cooling system

Post by Fair Weather Rider on Wed 31 Jan 2018, 1:07 pm

See pics of fan




avatar
Jameshambleton
Moderator
Moderator

Posts : 2694
Location : Bedale, North Yorkshire

Re: Cooling system

Post by Jameshambleton on Wed 31 Jan 2018, 9:12 pm

That doesn't look like an OEM rad so probably changing it was the better choice
avatar
Fair Weather Rider
the 800
the 800

Posts : 256
Location : Tenbury Wells

Re: Cooling system

Post by Fair Weather Rider on Wed 07 Feb 2018, 7:12 pm

All sorted, new rad and fan, thermos switch in rad, fan cuts in when the temp needle is half way, so happy with that. Had a few minor water leak issues from around the thermostat, but a new O ring on the plastic filler neck bit and nipped up the hoses put it right.
Ran it to working temp took tank back off topped up coolant and Bob's your uncle.
Daft isn't it that you have to take the tank off to top up.
Waiting for weather to warm up now. Very Happy Very Happy Very Happy Very Happy
avatar
motofan
Barry Sheene
Barry Sheene

Posts : 96
Location : Normandie, France

Re: Cooling system

Post by motofan on Sat 10 Feb 2018, 1:27 pm

Fair Weather, hello, shurely you only need to fill the rad when you do any work on it and you refill it, topping up is done via the plastic expansion bottle as in a car?
Certainly I won't be arsed to take the tank off every time! Smile
Dave
avatar
Fair Weather Rider
the 800
the 800

Posts : 256
Location : Tenbury Wells

Re: Cooling system

Post by Fair Weather Rider on Sat 10 Feb 2018, 2:22 pm

@motofan wrote:Fair Weather, hello, shurely you only need to fill the rad when you do any work on it and you refill it, topping up is done via the plastic expansion bottle as in a car?
Certainly I won't be arsed to take the tank off every time! Smile
Dave
Have had so many problems with cooling, wanted to make sure there wasn't an air lock, will trust expansion tank now I know it's full, but will be keeping an eye on it.
avatar
motofan
Barry Sheene
Barry Sheene

Posts : 96
Location : Normandie, France

Re: Cooling system

Post by motofan on Sat 10 Feb 2018, 5:44 pm

Aha, you have my entire understanding, things like that irk me as well. Smile
avatar
Jameshambleton
Moderator
Moderator

Posts : 2694
Location : Bedale, North Yorkshire

Re: Cooling system

Post by Jameshambleton on Sat 10 Feb 2018, 7:49 pm

If there us a leak then air will get in the system so the overflow tank will not siphon into the main system. I found this out almost too late
avatar
motofan
Barry Sheene
Barry Sheene

Posts : 96
Location : Normandie, France

Re: Cooling system

Post by motofan on Sat 10 Feb 2018, 8:34 pm

Good point, I make a habit of squeezing my pipe(radiator I mean, OOER) when the motor's hot and verifying that it's turgid! If it's soft then it's not holding pressure ie. leaking somewhere.

Sponsored content

Re: Cooling system

Post by Sponsored content


    Current date/time is Thu 19 Jul 2018, 10:30 am