Centering carb jet

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James k
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Centering carb jet

Post by James k »

Hi,
I've just rebuilt my carb whilst on holiday in Germany. I put everything together carefully and centred the jet guide by eye before bolting it up. Now it's back together, the piston rises freely and falls with a click, just as it should. I didn't need to make any adjustment.

The question is, does this sound right? Did I just luckily get it right first time? I ask because I've heard a lot about centering the jet and how fiddly it is so I wonder if there's more to it. The piston falls with a clunk like it did before the rebuild. Is there anything else I should be looking for to make sure the jet is centred?

Thanks,
James
philthehill
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Re: Centering carb jet

Post by philthehill »

James
The jet should fall with a clunk as it hits the carb body.
Make sure that the clunk is still there when the jet is at it normal working position i.e. when the carb is back on the car and being used.
It sounds as if you have centered the jet correctly.

Well done.

http://sucarb.co.uk/technical-hs-type-c ... djustments

Phil

mogbob
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Re: Centering carb jet

Post by mogbob »

James
+1 for Phil's comments. I'm sure you've got it on your list but don't forget to put fresh oil in the carb once it's
back on the engine. Air filter need replacing at this stage ( whilst it's off the carb ) ?
Bob
RobThomas
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Re: Centering carb jet

Post by RobThomas »

I tend to drop the piston down so that the needle centres the jet for me already. Then just tighten and check. Fiddly job, sometimes. :D
Cardiff, UK
James k
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Re: Centering carb jet

Post by James k »

Thanks for the replies, sounds like it is centred then. I was worried because it didn't need any adjustment so I thought there must be more to it. I won't get to try it on the engine until next week when I'm back in England but it all seems to have gone well. The only problem is that I broke one of the throttle disc screws whilst bending the ends out. I bent them to the same extent as the old ones but that proved too much and one snapped. I'll have to order some new ones before I can fit it to the engine!

In terms of the air filter, I fitted a new one about 2000 miles ago so I think it ought to be okay. I am waiting to get a new air filter base and mounting plate though as the stud has sheared off.

James
James k
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Re: Centering carb jet

Post by James k »

Here are some pictures.

Before:
WhatsApp Image 2018-08-07 at 19.02.27.jpeg
WhatsApp Image 2018-08-07 at 19.02.27.jpeg (94.02 KiB) Viewed 1276 times
After:
WhatsApp Image 2018-08-07 at 19.02.45.jpeg
WhatsApp Image 2018-08-07 at 19.02.45.jpeg (93.36 KiB) Viewed 1276 times
WhatsApp Image 2018-08-07 at 19.02.45 (1).jpeg
WhatsApp Image 2018-08-07 at 19.02.45 (1).jpeg (102.45 KiB) Viewed 1276 times
mogbob
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Re: Centering carb jet

Post by mogbob »

James
After all that cleaning and polishing I reckon you're due a holiday !!
You've made a good job of that.
Bob
mogbob
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Re: Centering carb jet

Post by mogbob »

James
After all that cleaning and polishing I reckon you're due a holiday !!
You've made a good job of that.
Bob
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