Author Topic: timing cover  (Read 1434 times)

Offline anjimehra

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timing cover
« on: 08.04. 2013 08:43 »
Hi
Just a general question pertaining to Aluminium  timing covers. Whats the max temp one can heat it to ? w/o distortion?
Thanks
Anji

Offline Briz

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Re: timing cover
« Reply #1 on: 08.04. 2013 10:38 »
How hot do you want to get it?
I doubt anyone has a number in degrees they could tell you.
Welding the diecast ones (most except early plunger ones) does warp them a little bit, but not usually too badly to mill flat again. I suspect the thicker sand cast ones fare better.
Careful pre-heating helps,as does bolting them down, maybe to an old crankcase.

Online RichardL

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Re: timing cover
« Reply #2 on: 08.04. 2013 20:46 »
Anji,

You've probably exceeded the max just sitting in the midday Indian sun. *smile*

Richard L.

Plan on signing up for the world-wide 2020 DISTINGUISHED GENTLEMAN'S RIDEon September 27, 2020 (if it's not cancelled and we are free to move about by then). Watch website at https://www.gentlemansride.com for details.

Offline anjimehra

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Re: timing cover
« Reply #3 on: 10.04. 2013 05:18 »
How hot do you want to get it?
I doubt anyone has a number in degrees they could tell you.
Welding the diecast ones (most except early plunger ones) does warp them a little bit, but not usually too badly to mill flat again. I suspect the thicker sand cast ones fare better.
Careful pre-heating helps,as does bolting them down, maybe to an old crankcase.

Hi Briz
Thanks for feedback. Actually I need the info for my Dommi cover as the steel pressure release valve has jammed in the cover due to years of non use.

Offline anjimehra

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Re: timing cover
« Reply #4 on: 10.04. 2013 05:22 »
Anji,

You've probably exceeded the max just sitting in the midday Indian sun. *smile*

Richard L.



Hi Richard
How are you. Long time no speak !!! Youre right. Current temp exceeds 40 Deg C & hotter on tarmac. Come & experience how different from being snowbound over Easter !!!!!

Actually need to free the pressure release valve on my dommi which is stubbornly stuck in the cover.Holding up the restoration
Anji

Online BSA_54A10

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Re: timing cover
« Reply #5 on: 11.04. 2013 11:48 »
The alloy melts at around 700 C
Solution treating is done around 400 C
For normal bearing replacements you would be around 200 C.

The temperature is not as important as how the heat is applied and how the cover is supported while being heated.

You can go hotter in a convection oven than you could on top of the BBQ hot plate.


So go over 400 and you will have to re heat treat the case.
The process is called solution treating & artifical ageing.
Over 200 without proper support & you risk deforming the cover.
Bike Beesa
Trevor

Offline anjimehra

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Re: timing cover
« Reply #6 on: 15.04. 2013 07:30 »
The alloy melts at around 700 C
Solution treating is done around 400 C
For normal bearing replacements you would be around 200 C.

The temperature is not as important as how the heat is applied and how the cover is supported while being heated.

You can go hotter in a convection oven than you could on top of the BBQ hot plate.


So go over 400 and you will have to re heat treat the case.
The process is called solution treating & artifical ageing.
Over 200 without proper support & you risk deforming the cover.

Thanks. Will sneak the cover into the oven when the wife's out & see what happens

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Re: timing cover
« Reply #7 on: 15.04. 2013 10:28 »
You will be sleeping out side with the dog for a month.
If you have a BBQ then pinch a shelf out of the oven, support it above the hot plate .
Engine oil smoking in the oven is a very pungent smell.
Bike Beesa
Trevor

Offline A10Boy

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Re: timing cover
« Reply #8 on: 15.04. 2013 13:20 »
Put it in the dishwasher first..  *smile*
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Andy

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Online bsa-bill

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Re: timing cover
« Reply #9 on: 15.04. 2013 13:25 »
one of mine must have a bit of bend, it seems to pivot in the centre somewhere until screwed up, then is quite oil tight so some flex with them also
All the best - Bill
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Online Greybeard

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Re: timing cover
« Reply #10 on: 15.04. 2013 15:34 »
Engine oil smoking in the oven is a very pungent smell.

Brake fluid smells lovely. Not!