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View Full Version : Pointy running very hot.


Heefy
04-09-12, 08:17 PM
Made the 40 mile journey home tonight, after having to jump start the bike. Bike had been running for 10-15 mins, stationary. On the journey the temp just kept going up all,the way to 130 degrees C. I couldnt hear the fan at all, but that may be that I couldn't hear it over the other noise.

The temp did not go up and down at all. Is the thermostat knackered or air in the coolant system? There is water in the reservoir.

Any thoughts or checks I can do please?

Cheers

H

MJC-DEV
05-09-12, 08:44 AM
Something very wrong, sounds like no fan as this will keep temp below about 105C. Fan will be pretty noisy and you will feel the air blast from it.
Suggest you check and change the fan switch in the radiator.

jambo
05-09-12, 09:51 AM
First things first, check the fan is functioning.

On the right hand side of your radiator is a thermo switch that brings the fan on over a certain temperature for coolant in the radiator. The sensor which feeds your dash display comes from a different sensor closer to the engine block.

Unplug the connection to this sensor, and short-circuit the wires that go into it with a bit of insulated wire or similar, if the fan comes on (ignition on but engine doesn't need to be running) then the fan and circuit are OK, and it's worth testing the thermo switch. If the fan doesn't run even with this switch replaced with a piece of wire, then you need to check the fan's fuse if it has a separate one (can't remember) and fault find the fan & power to it.

Jambo

Heefy
05-09-12, 09:53 AM
Thanks for your reply. Today I checke the bike on the way to work, which is all A roads and motorway and it was fine. Gets up steadily to 89 degrees C, then the thermostat kicks in and it drops to 83. This is repeated for the whole journey.

I will start looking for the switch. Obviously the 15 mins idle, whilst stationary did it no good.

Cheers Heefy

Heefy
05-09-12, 09:59 AM
Thanks Jambo. Great advice. Just what I needed. I will have a look at it later today and let you know.


Cheers Heefy.

Purity14
05-09-12, 10:20 AM
I rode without a fan on my old pointy for months.
Engine off at lights etc, never had any overheating problems.
As you say - when idling, it would just build up.

mufman
05-09-12, 10:22 AM
How fast you were riding? If you were doing at least 20mph or so (simply moving...) than the temp has to be around 85 (+/-) regardless the fan is functional or not....it never kicked of on my bike while riding...not even on hot days in Alps.

So in my opinion, fan is not your main problem.

Did you touch the hoses going to radiator? Were they hot? This is what I would start with. If they were cold than your thermostat is KO....or maybe a water pump. If they were hot, there might be something more serious..might be something wrong around cylinder's heads.

I would find out if the water circulates through radiator first (by checking those hoses - in and out).

Heefy
06-09-12, 06:34 PM
I have now checked the radiator fan switch by placing a bit of wire across the two contacts of the switch. The fan instantly came on. I assume this means the switch is dead. The fuse is under the passenger seat and is fine.

I will check the pipes as suggested tomorrow.

Thanks again all.

Heefy

jambo
06-09-12, 07:10 PM
Go for a ride to let the bike get up to temp, then stop and let it idle, watch the temperature, if it goes up over about 107 without the fan kicking in, I'd say the fan switch has probably had it.

Jambo

Kenzie
06-09-12, 07:31 PM
I think a Suzuki mech said the fan should kick in at 102c.

jambo
06-09-12, 08:18 PM
I think a Suzuki mech said the fan should kick in at 102c.

Sounds about right, but the temperature sensor that feeds the dash, and the fan switch are in 2 separate locations, so it's not as exact as all that :)

Jambo

mufman
10-09-12, 11:03 AM
The main thing here is that if the temperature goes up over 100 degreees in these days while moving (not standing on traffic lights) than there is another problem than "just" possible fan (or fan's sensor) failure.

jambo
10-09-12, 12:24 PM
The main thing here is that if the temperature goes up over 100 degreees in these days while moving (not standing on traffic lights) than there is another problem than "just" possible fan (or fan's sensor) failure.
I agree entirely. However, this:
On the journey the temp just kept going up all,the way to 130 degrees C. I couldnt hear the fan at all, but that may be that I couldn't hear it over the other noise.

The temp did not go up and down at all. Is the thermostat knackered or air in the coolant system? There is water in the reservoir.


And this:
Today I checke the bike on the way to work, which is all A roads and motorway and it was fine. Gets up steadily to 89 degrees C, then the thermostat kicks in and it drops to 83. This is repeated for the whole journey.

Seem contradictory in terms of what the current state of affairs is, with the 2nd one seeming to vindicate the thermostat's operation.

Which is why I was concentrating on the fan initially. Clearly (as you've stated) if the coolant isn't being circulated through the radiator properly, then the fan's not going to help.

Jambo

mufman
10-09-12, 03:37 PM
Oh, my bad. I've overlooked the second message from Heefy. Then if it's OK while moving the fan would be the thing I would concentrate, as you guys have suggested.

Heefy
11-09-12, 06:09 PM
I have let the bike warm up and then checked the the hose coming from the lower right handside of the rad. It was hot and the liquid was free moving.

Today I got my new fan switch, so plastics off and drained the rad and the reserve tank. Fitted the new switch. Made up a 60/40 mix of coolant and distiller water and refilled. Bled the air, quick ride and rechecked the levels. All good.

Now the bike runs as before. Up to 89 degrees C, then the thermostat opens and the temp goes down to 81. This is a continual cycle. I then left the bike running on the side stand. At 103 the fan kicked in and the temp dropped back to 91 and the fan switched off.

All seems ok now.

The switch is located on the right of the rad, directly under the hose.

http://img259.imageshack.us/img259/8586/1347389929865.jpg