Installing a timing belt

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wally318
Posts: 260
Joined: Sun Jun 05, 2011 1:06 am
Location: Kelowna, British Columbia

Installing a timing belt

Post by wally318 »

In dealing with some leaks on my Colchester Chipmaster headstock
I decided to remove all the belts to give the outboard gears a bit of cleaning
as well as a better view vantage of where the oil was leaking.
In removing the timing belt between the clutch shaft and main spindle
the timing belt tore. It was quite old. At the clutch shaft end it had
to climb over 2 V-belt grooves that are larger than the timing pulley.
When come time to reinstall a new timing belt is there a trick to
mounting the timing belt in this difficult setting?
Can the belt be warmed a bit to aid stretching?
I'm hoping to get it back on without dismantling the clutch shaft.
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rklopp
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Location: NorCal

Re: Installing a timing belt

Post by rklopp »

The cords will not allow the belt to stretch any appreciable amount. I am afraid you are stuck with some disassembly and reassembly. I had to do similar to replace the belt between the motor and variator input. Even then, it was an ordeal getting the belt on because the shaft center distance is built into the machine.


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Bill Shields
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Re: Installing a timing belt

Post by Bill Shields »

Ditto to above.

Be prepared to fully check and replace all belts while you are at it.

It's an all or nothing situation with belts of this type. They are specifically designed to not stretch under any circumstances.
Too many things going on to bother listing them.
wally318
Posts: 260
Joined: Sun Jun 05, 2011 1:06 am
Location: Kelowna, British Columbia

Re: Installing a timing belt

Post by wally318 »

Well I got into it.
Had to pull the front cover of clutch/brake. To release the inner shaft
out the back. Then everything was somewhat straight forward.
Time for a good clean up anyway. And I'll put a new oil seal in while I'm at it.
Was leaking a bit of oil at the back of the clutch.
had the variator/motor timing belt on and off several times.
With one of the retainer rings off went on and off not too bad.
For me it was just a very awkward spot to get at/see.
My ribs were almost bruised.
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rklopp
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Location: NorCal

Re: Installing a timing belt

Post by rklopp »

Did you remove the cupboard door and cupboard from the base to access the motor timing belt? It took me a while to realize that was the best way to access the belt.
wally318
Posts: 260
Joined: Sun Jun 05, 2011 1:06 am
Location: Kelowna, British Columbia

Re: Installing a timing belt

Post by wally318 »

That was one of the first things I did.
When I bought it, the previous owner removed the 600V
3 phase motor and sent along the 2 Hp doerr motor that
came along with it. So access from that side made alignment of
the pulleys realativley easier.
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