Author Topic: A10 revs hanging when hot.  (Read 407 times)

Offline K1100

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Re: A10 revs hanging when hot.
« Reply #15 on: 23.05. 2020 12:28 »
I might have worked this out.
The pilot jet that is in my attached pic is not adjustable. My mistake. It should be screwed right up and home, and the pilot jet retaining nut screwed tight onto it so it all stays put. If that jet was loose, that might have been causing my rev holding issue. So the petrol drip tray position doesn’t matter, because I don’t need access to the jet to adjust it... the jet just has to be screwed right up and tight and the retaining nut and fibre washer lock it in place.

Offline K1100

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Re: A10 revs hanging when hot.
« Reply #16 on: 23.05. 2020 16:18 »
Sorted... it was the loose pilot jet and pilot jet retaining nut

I now know about 10x more about carbs than I did two days ago so thankyou to everyone who put thought into my problem and helped me to sort it.

PS I know from the paperwork with the bike that the guy I bought it from in 2012 had a few years earlier shipped it from the UK to NZ for a long touring holiday with his wife and camping gear.

Offline TimK

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Re: A10 revs hanging when hot.
« Reply #17 on: 25.05. 2020 01:23 »
The pilot jet is not making sense to me. When I unscrewed the pilot jet retaining nut the float chamber contents drained out. The pilot jet was loose. The retaining nut screws onto the jet so I can't see how to adjust it. Wherever I set it - say 1 1/2 turns out - it will screw back in as I thread the retaining nut onto it. What am I missing?(apart from a brain)
And how is it possible to adjust tickover while the engine is running if the fuel drains out? Haynes is useless and I can't find anything online that helps.
Hi K1100
The screw you should be moving to adjust the pilot jet is the horizontal one directly above the pilot jet, this controls the amoount of air flow of air across the top of the pilot jet. The pilot jet should be screwed fully home - but not too tight as it's only brass.
Cheers
Tim
Tim Kerridge
Australia

Offline Swarfcut

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Re: A10 revs hanging when hot.
« Reply #18 on: 25.05. 2020 07:42 »
    Brass jets  and Mazak Carb Bodies can have a strong affinity. I found this out the hard way simply adjusting the tickover on a Monobloc.  Thought the adjuster screw was a bit tight, next thing the damn thing sheared off, effectively rendering a good carb just a bit useless. These days a smear of silicone grease on such threads solves the problem for me.

 The earlier 276 carb has a much less tight thread and a locknut on the adjuster, never a problem here.

 Swarfy.

Offline K1100

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Re: A10 revs hanging when hot.
« Reply #19 on: 01.06. 2020 22:13 »
Hi Tim and Swarfy... thanks for your help. All is going well now - starts easily, tickover steady and rev hanging gone.
It was the loose pilot inside the brass nut that caused me a mental flip.. because the jet was loose, I assumed it was adjustable, whereas it was just loose because it had come undone.