steaming rad cap and no fan!

[oldgreyandslow]

The saga of my sorry bike continues:

New plugs, the right jets, carbs clean, float height done, new coolant, oil, starts OK, runs a bit ropey initially but then seems OK, lots of fannying around with the idle speed adjuster. Still got the smoke, but not as much and it reduces when warmed up, not so much of an issue, its the warming up that is though.

Ran it with the rad cap off, plenty steam, put cap back on, still steam but it seemed to be coming out of the cap?

Got to well over the middle of the gauge and the fan didn't come on, I guess its time to check the fuse, fan switch etc

I wonder if I'll ever get this bloody thing back on the road!

[Dynamohum]

fan doesn't cut in till well up the guage pos about 110c i think. you can test fan by earthing the spade that goes onto the fan temp sensor switch on the bottom rad by removing and earthing it elswhere fan should cut in . rad cap may be fkd or it may overflow pipe to expansion tank thats trapped or badly routed

[oldgreyandslow]

Thanks
I have found a fuse blown in the fusebox, its the 10A one on its own next to a gap, not used slot, then there's 3 others, I hope this is the fan fuse, I'll check the circuit tomorrow

[Man_Named_Dave]

Fan should cut in at 98 degrees.

Are you sure the coolant is circulating? If you're bike's in that bad a state, then I would expect the lower rad to have a fooked core.

[oldgreyandslow]

Fan should cut in at 98 degrees.

Are you sure the coolant is circulating? If you're bike's in that bad a state, then I would expect the lower rad to have a fooked core.

Both lower hoses were warm to the touch, how would I check if the water is circulating?

[Neosophist]

Fan should cut in at 98 degrees.

Are you sure the coolant is circulating? If you're bike's in that bad a state, then I would expect the lower rad to have a fooked core.

Both lower hoses were warm to the touch, how would I check if the water is circulating?

Right.

Fan kicks in when needle is near the top!.

If you put the ignition on (no need to run the bike) and remove the wire from the fan switch and touch it to the frame the fan should come on, if it doesn't your fan is busted.

If it does get the bike red hot and see! :D (make sure you re-connect wire to fan-switch first)

When you start the bike and its cold if you have the rad cap off and rev the bike you should see the water moving, after the temp gets to half way the thermostat opens and the water should move a lot.. if you rev it up to aroudn 5000rpm on the over-run the water should overflow.

You may have a leaking rad-cap too if it's steaming a lot from there.

You can always take the cover off the water-pump and check the blade condition and that it spins.. mine had no blades in it! :O

Im' guessing you just need to get it hotter.. if water starts goign into the expansion tank before the fan is on and the temp gauge isn't at the top then the cap is no good

[oldgreyandslow]

Right.

Fan kicks in when needle is near the top!.

If you put the ignition on (no need to run the bike) and remove the wire from the fan switch and touch it to the frame the fan should come on, if it doesn't your fan is busted.

If it does get the bike red hot and see! :D (make sure you re-connect wire to fan-switch first)

When you start the bike and its cold if you have the rad cap off and rev the bike you should see the water moving, after the temp gets to half way the thermostat opens and the water should move a lot.. if you rev it up to aroudn 5000rpm on the over-run the water should overflow.

You may have a leaking rad-cap too if it's steaming a lot from there.

You can always take the cover off the water-pump and check the blade condition and that it spins.. mine had no blades in it! :O

Im' guessing you just need to get it hotter.. if water starts goign into the expansion tank before the fan is on and the temp gauge isn't at the top then the cap is no good

This is related to my fan not working post (since deleted because it does!), Haynes advises connecting 12v to the fan wiring, which I did with a jumper from the battery positive. no go. However I have just removed the wire from the fan switch and grounded it and the fan runs. After posting this yesterday I did discover the fan fuse was blown!

When I ran the bike I did blip the throttle and water did indeed overflow, all over the bloody front wheel, brake calipers, garage floor, etc.

I didn't notice any movement though, but its difficult to see into the rad tbh, well it was for me!

Perhaps I should just run it until it gets hotter, with the cap on, and see what happens.

I'll go see if I can get a spare rad cap just in case

[Man_Named_Dave]

My fan sender switch was kaput, so instead of buying a new one I now have a manual switch. It's worth considering as a cheaper option.

[hardnutdvd]

My fan sender switch was kaput, so instead of buying a new one I now have a manual switch. It's worth considering as a cheaper option.

you mean it's worth considering as the 'bodgers' option

[Man_Named_Dave]

My fan sender switch was kaput, so instead of buying a new one I now have a manual switch. It's worth considering as a cheaper option.

you mean it's worth considering as the 'bodgers' option

Not really, it's perfectly reliable and cheaper than the £45 on David Silver.