Mechanical fan clutch always roaring

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Limey
Posts: 116
Joined: Fri Jun 17, 2022 5:17 am

Mechanical fan clutch always roaring

Postby Limey » Thu Sep 01, 2022 7:47 pm

Lately I’ve noticed that my mechanical fan clutch appears to be stuck , meaning every time I pull away from a stop sign or red lights the viscous fan roars. Originally it only did it on initial cold start ups. But now it seems to always be engaged. My MPG has also been reduced to around 14mpg but other factors could be playing into that.


Limey
Posts: 116
Joined: Fri Jun 17, 2022 5:17 am

Re: Mechanical fan clutch always roaring

Postby Limey » Sat Sep 03, 2022 9:19 pm

MPG seems to fine when driving with little to no stop to traffic. Around 22MPG.

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VStar650CL
Posts: 501
Joined: Wed Dec 09, 2020 6:19 pm

Re: Mechanical fan clutch always roaring

Postby VStar650CL » Sun Sep 04, 2022 6:36 am

Give it a spin when cold and then again warm. There should be a large difference in resistance, it should be much stiffer when warm. If it isn't, or if it's stuck solid, then it's time for a new clutch.

Limey
Posts: 116
Joined: Fri Jun 17, 2022 5:17 am

Re: Mechanical fan clutch always roaring

Postby Limey » Sun Sep 04, 2022 6:49 am

VStar650CL wrote:
Sun Sep 04, 2022 6:36 am
Give it a spin when cold and then again warm. There should be a large difference in resistance, it should be much stiffer when warm. If it isn't, or if it's stuck solid, then it's time for a new clutch.
Ok thanks.

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AS_The_Crow_Flys
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Joined: Wed Jun 15, 2022 1:28 pm

Re: Mechanical fan clutch always roaring

Postby AS_The_Crow_Flys » Fri Sep 09, 2022 9:36 am

My redneck test for this was to grab a small towel and see if i could stop the fan from spinning when warm... I supposed turning the engine off after warming it up is a little safer.

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Wahooo
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Joined: Sat Oct 02, 2021 12:49 pm

Re: Mechanical fan clutch always roaring

Postby Wahooo » Fri Sep 09, 2022 11:01 am

Used to call that, shaking hands with death :lol:

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VStar650CL
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Joined: Wed Dec 09, 2020 6:19 pm

Re: Mechanical fan clutch always roaring

Postby VStar650CL » Fri Sep 09, 2022 1:20 pm

Wahooo wrote:
Fri Sep 09, 2022 11:01 am
Used to call that, shaking hands with death :lol:
In some countries they cut hands off for stealing. Here only our vehicles do it. :P

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AS_The_Crow_Flys
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Joined: Wed Jun 15, 2022 1:28 pm

Re: Mechanical fan clutch always roaring

Postby AS_The_Crow_Flys » Sat Sep 10, 2022 1:28 am

VStar650CL wrote:
Fri Sep 09, 2022 1:20 pm
Wahooo wrote:
Fri Sep 09, 2022 11:01 am
Used to call that, shaking hands with death :lol:
In some countries they cut hands off for stealing. Here only our vehicles do it. :P
It was a plastic fan so… probably not that dangerous.

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VStar650CL
Posts: 501
Joined: Wed Dec 09, 2020 6:19 pm

Re: Mechanical fan clutch always roaring

Postby VStar650CL » Sat Sep 10, 2022 5:47 am

Paper can cut you. Once as child, following a Florida hurricane, I found a blade of sawgrass stuck clean through the side of a telephone pole outside my grandpa's house. Almost anything moving can make a mess, it all depends on angle and speed. :wink:


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