M20 fan torque

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xavier
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Post Mon Jan 18, 2021 2:37 am

I have changed the timing belt and other odds and ends. At reassembly how tight does the fan have to be screwed on? It is negative thread, but will it tighten more as the engine spins?
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BenHar
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Post Mon Jan 18, 2021 5:55 pm

It will self tighten.

Ben
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martauto
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Post Tue Jan 19, 2021 5:06 pm

xavier wrote:
Mon Jan 18, 2021 2:37 am
It is negative thread,
Never heard this one before and I have cut threads for all over the world, if this is your "term" do you mind if I use it ?? Brilliant !!

Mart.
Only the E46 cab left now.
Just got too old.
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reggid
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Post Tue Jan 19, 2021 8:59 pm

a negative thread is still a thread...lol

it is LH threaded so will self tighten under load. However i just nip it up as when the engine suddenly accelerates/decelerates (one of those lol) the fan with its inertia wants unwind
E30 325is with M20B31
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martauto
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Post Wed Jan 20, 2021 5:45 pm

reggid wrote:
Tue Jan 19, 2021 8:59 pm
a negative thread is still a thread...lol

it is LH threaded so will self tighten under load. However i just nip it up as when the engine suddenly accelerates/decelerates (one of those lol) the fan with its inertia wants unwind
I know that you ment left hand but really wondered where the term came from?
I asked at work today and even us older (in their sixties )guy`s had not come across it .

Mart.
Only the E46 cab left now.
Just got too old.
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xavier
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Post Sat Jan 23, 2021 3:31 pm

I don’t know where I originally heard the term negative thread. Maybe at school in Scotland in the 1970s? Perhaps over here in Australia as an adult? Maybe it just flew into my head one day? It’s just the term I use. Perhaps I need to get out more?
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martauto
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Post Sun Jan 24, 2021 1:20 pm

xavier wrote:
Sat Jan 23, 2021 3:31 pm
I don’t know where I originally heard the term negative thread. Maybe at school in Scotland in the 1970s? Perhaps over here in Australia as an adult? Maybe it just flew into my head one day? It’s just the term I use. Perhaps I need to get out more?
That makes two of us then :banana: :banana: :banana: :banana:

Mart.
Only the E46 cab left now.
Just got too old.