FCS Thermal Creep Switch Issues
Outstanding HDF Member
Joined: Oct 2008
Posts: 2,981
Likes: 48
From: Northern Illinois
Okay, so on a cold engine, with the thermal switch in play, manual switch does nothing.
Once the engine warms up and the thermal switch "closes", you can use the manual switch to operate the fans.
Makes sense, I had it in my mind that the manual switch always acted as an "override", but I guess it can't with the Thermal.
Thanks
Well, just installed the new switch.
This time, I coated both the upper and lower portion of the Fins, the switch itself, and I also laid a bead of silicone against the cylinder wall itself.
I just used a piece of wood and pushed the switch in with my hand, no tapping with a mallet. It got pretty tight where the fins narrow, so rather than try to force it, I just stopped.
I think we're good, I'm gonna just leave it alone until tomorrow and let the silicone fully cure.
There is a good 3/16" to 1/4" air gap between the switch and the actual wall of the cylinder. Actually not an "air gap" anymore, cause it's filled in with silicone.
My "pushing tool"
I'm gonna post this over on my install thread also, in case someone doesn't see this thread.
This time, I coated both the upper and lower portion of the Fins, the switch itself, and I also laid a bead of silicone against the cylinder wall itself.
I just used a piece of wood and pushed the switch in with my hand, no tapping with a mallet. It got pretty tight where the fins narrow, so rather than try to force it, I just stopped.
I think we're good, I'm gonna just leave it alone until tomorrow and let the silicone fully cure.
There is a good 3/16" to 1/4" air gap between the switch and the actual wall of the cylinder. Actually not an "air gap" anymore, cause it's filled in with silicone.
My "pushing tool"
I'm gonna post this over on my install thread also, in case someone doesn't see this thread.
Outstanding HDF Member
Joined: Oct 2008
Posts: 2,981
Likes: 48
From: Northern Illinois
Are you sure? I could be wrong, but I don't think I've ever seen Hi Temp 650 degree RTV in Black. Copper I think, but not Black. I could be wrong though.
I actually cleaned the extra up after taking this pic, you can hardly see it on the bike after mounting the Fan and Mini Beast. Looks a lot worse than it actually is on the close-up photo.
Are you sure? I could be wrong, but I don't think I've ever seen Hi Temp 650 degree RTV in Black. Copper I think, but not Black. I could be wrong though.
I actually cleaned the extra up after taking this pic, you can hardly see it on the bike after mounting the Fan and Mini Beast. Looks a lot worse than it actually is on the close-up photo.
I actually cleaned the extra up after taking this pic, you can hardly see it on the bike after mounting the Fan and Mini Beast. Looks a lot worse than it actually is on the close-up photo.
Road Warrior
Joined: Dec 2012
Posts: 1,335
Likes: 5
From: CT
Are you sure? I could be wrong, but I don't think I've ever seen Hi Temp 650 degree RTV in Black. Copper I think, but not Black. I could be wrong though.
I actually cleaned the extra up after taking this pic, you can hardly see it on the bike after mounting the Fan and Mini Beast. Looks a lot worse than it actually is on the close-up photo.
Sent from my Galaxy Nexus
VersaChem Mega Black - O.E.M. High-Temp Silicone Gasket Maker
Part Number: 99839
Line: VER
manufacturer's defect warranty
UPC: 78727998399
3 Oz.
Detailed Description
Designed to exceed O.E.M. specifications for silicone gasket makers. Exceeds O.E.M. spec. GM9985675 Low odor Non-corrosive Sensor safe-can be used on all engines High temperature resistance up to +650 Degrees F (+343 Degrees C) Resists oil, water, antifreeze mixtures, greases & transmission fluid
Outstanding HDF Member
Joined: Oct 2008
Posts: 2,981
Likes: 48
From: Northern Illinois
The VersaChem Mega Black is 650 degree RTV. It is O'Reilly's brand. It's not that any of it is probably that noticeable once you install the horn and fans, but the black does tend to blend in better.
VersaChem Mega Black - O.E.M. High-Temp Silicone Gasket Maker
Part Number: 99839
Line: VER
manufacturer's defect warranty
UPC: 78727998399
3 Oz.
Detailed Description
Designed to exceed O.E.M. specifications for silicone gasket makers. Exceeds O.E.M. spec. GM9985675 Low odor Non-corrosive Sensor safe-can be used on all engines High temperature resistance up to +650 Degrees F (+343 Degrees C) Resists oil, water, antifreeze mixtures, greases & transmission fluid
VersaChem Mega Black - O.E.M. High-Temp Silicone Gasket Maker
Part Number: 99839
Line: VER
manufacturer's defect warranty
UPC: 78727998399
3 Oz.
Detailed Description
Designed to exceed O.E.M. specifications for silicone gasket makers. Exceeds O.E.M. spec. GM9985675 Low odor Non-corrosive Sensor safe-can be used on all engines High temperature resistance up to +650 Degrees F (+343 Degrees C) Resists oil, water, antifreeze mixtures, greases & transmission fluid
Sure, you could have told me before
Like I said though, you can hardly see it now.
Sorry dude, you should have said that you were going to use that copper crap! Well you will know in the future that there is a black option.
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Tourer
Joined: Mar 2009
Posts: 413
Likes: 16
From: Killeen, Tx
I used the Ultra Black RTV.
When I was at the auto parts store I saw the red high temp and thought "this will look like crap". So I searched some more and found the Ultra black which is rated for a temperature range of -65°F to 500°F.
So far so good with the snap switch.
When I was at the auto parts store I saw the red high temp and thought "this will look like crap". So I searched some more and found the Ultra black which is rated for a temperature range of -65°F to 500°F.
So far so good with the snap switch.
Last edited by Tx_Rider; Nov 10, 2013 at 07:09 AM.
I have been running one of the snap switches but it was an earlier sample calibrated at 110C, otherwise same switch, mine comes on pretty consistently at 250F CHT then drops back down about 230-240 depending on conditions. The switches I have been shipping are calibrated at 105C and so far feedback suggest they are coming on about 240F give or take. I was concerned about the "off" temperature which is about 70% of the "closed" calibration, but the fan don't seem to be running excessively long after shut down, so I'm going to order some samples in 100C calibration and see what they do. A 10F drop may do the trick to get them on in colder weather operations, I'm actually surprised that some are not coming on in 50F ambient temps, because head temps still get very high in cold weather operation. There are a lot of variables that influence the function of these switches so I'm working on install instructions right now for this new switch, I think a consistent install will be a good start to help to narrow the temp differences amongst reports, besides that I am just way over due to publish them. Tonight I'm installing one of the 105C switches on my bike, same one that I have been shipping for a month or so, and see how much difference there is. I think this snap switch is well suited for the application and its more durable than the creep. I know a lot of people like the 190F operation of the creep, myself included, but honestly the system doesn't hold the CHTs at 190F, so really a switch that comes on at the low end of an engine's "normalized" operating temp should be a decent match. More to follow as it develops. Thanks for the participation and contributions.
Jason
Jason
I just installed my FCS fans w/snap switch. The weather here is crap, so all I can do is just an idle heat up & down.
I installed the snap switch in the 3rd gap of the fins just under the heat sensor. I used the black HT RTV. If you look back in the bottom of the fin area there is a small pocket there that the switch will go into which puts it as close to the main head casting as you can get. Right on it.
Using my PV to monitor heat. In an idle test the fans initially came on at 177*f,,, warmed to 183*, then cooled to 179* & turned off the fans.
Fans back on at 180*,,, stayed on to peak at 204*. Idle for 30 min, & holding at 199* to 204*. No EITMS cycle.
Turned off the engine, fans stayed on down to 181* then off. Fans back on at 186* due to heat soak, then back off at 180*.
Engine temp dropped from there. The oil temp didn't have a chance to move up at all on my gauge which the sensor is in the oil pan. 1st temp on the gauge in 140*. Infra red temp of the pan was tops of 129*. If the oil was hot from riding it just would maybe influence maybe a little longer cool down. I'll let ya know how that works as soon as I can ride long enough to heat it up a bit.
Ride Safe
Ride Often !
Last edited by sloufoot; Nov 8, 2013 at 07:07 PM.