how to tell if thermostat is open? ('80 gl1100)

jml74 · #1

I resurrected an '80 GL1100 that had a blown head gasket and a dead thermal switch for the fan that had been replaced with a toggle switch hardwired into the fan circuit (likely the cause of the head gasket issue). I replaced the head gasket, the thermal switch for the fan, and the thermostat and got it running yesterday, but I'm not convinced everything is as it should be yet. I let it sit and idle on the lift for several minutes and the temperature gauge started to move, but it barely got out of the cold range and the fan never came on (there are other issues keeping me from taking it for a test ride just yet). All of the radiator hoses that I could safely reach were hot, but so was everything else on the motor. If everything is working as it should be, how long should it take for the temperature gauge to reach the normal range and for the fan to come on? Is there a way I can tell for sure whether or not the thermostat is open and the coolant is circulating?

Track T 2411 · #2

There are a lot of variables, but when I warmed up my bike a few times over the winter, it took about 10 minutes for the fan to start cycling. I would imagine it would be shorter in warmer weather.
I'm curious; did you happen to check the water pump for excessive play?

#3

Could be 15 or more minutes .... watch the gauge and don’t let it overheat ....

Gord(about one beer)Jones

#4

RAT wrote:SNIP

Gord(about one beer)Jones

Yea after his Nap

jml74 · #5

I was just being paranoid. I went out today to synch the carbs and eventually the gauge rose, the fan came on, and the gauge dropped back down; I didn't keep track of the time, but it was quite a few minutes (15 +/- is probably about right). Looks like it's all good on the cooling front.

Sidecar Bob · #6

It takes a long time for an engine to fully warm up at idle. It will warm up fastest under load but if you can't go anywhere varying the throttle will help.

jml74 · #7

Sidecar Bob wrote:It takes a long time for an engine to fully warm up at idle. It will warm up fastest under load but if you can't go anywhere varying the throttle will help.

Well, the carbs were way out of whack and it was my first time trying to do a synch, so there was definitely some variance in the throttle.

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how to tell if thermostat is open? ('80 gl1100)

how to tell if thermostat is open? ('80 gl1100)

Re: how to tell if thermostat is open? ('80 gl1100)

Re: how to tell if thermostat is open? ('80 gl1100)

Re: how to tell if thermostat is open? ('80 gl1100)

Re: how to tell if thermostat is open? ('80 gl1100)

Re: how to tell if thermostat is open? ('80 gl1100)

Re: how to tell if thermostat is open? ('80 gl1100)