Jet head sticking on HS2 Carb

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Nickol
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Jet head sticking on HS2 Carb

Post by Nickol »

I have always suspected my 1098 Traveller from '69 to be running rich. So I have got hold of a Gunson colortune (pity they have to use american spelling) and connected it up.

Sure enough a bright yellow glow indicated a rich mixture so I strarted to screw in the Jet adjusting nut....and in ...and in until it would not go any further and the yellow glow was still there. Then I discovered that the jet head ( I am referring to terms indicated in the workshop manual page section BBB.5 ) was jammed slighly in the open position as when the choke is applied. It was easy to push up and of course the engine now running too lean, stopped.

No real problem, screwed the nut out again, restarted the engine and manged to get the nice blue flame with further adjustment.

I suspect however, that the jet head is jamming every time I do a cold start. Would it be safe to try and oil it hoping it will then stay free or will it be necessary to dismantle the carb?
Gott schütze mich vorm Sturm und Wind und Autos, die aus England sind.
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philthehill
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Re: Jet head sticking on HS2 Carb

Post by philthehill »

Page. BBB.5...…..Section BBB.6...…..Fig. BBB.6...…..Item: No. 3 Jet Head.

Disconnect the choke cable and see what happens.
The problem could lie with the choke cable and not the jet head.
The linkage and jet head do need to be well lubricated to function as it should.

Gunson Colortune is the trade name - a bit like Britool which is an acronym for The British Tool Company.

https://www.ebay.co.uk/itm/Gunson-Color ... Sw8R9amTc3

Nickol
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Re: Jet head sticking on HS2 Carb

Post by Nickol »

Many thanks I will give it a go.
Gott schütze mich vorm Sturm und Wind und Autos, die aus England sind.
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Nickol
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Re: Jet head sticking on HS2 Carb

Post by Nickol »

I have lubricated the jet head and started the engine twice now from cold. Cold at the moment being a relative term. Shortly afterwards have stopped the car and checked to see if it has stuck, which happily is not the case. Problem solved I think.
Gott schütze mich vorm Sturm und Wind und Autos, die aus England sind.
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Bornfree
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Re: Jet head sticking on HS2 Carb

Post by Bornfree »

I’m wondering if I have a similar problem, with the jet head not retracting without the choke. What grade oil is best for the lubrication please?
Owlsman
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Re: Jet head sticking on HS2 Carb

Post by Owlsman »

Sorry, I can't really bring much to this party except to say that pretty much ever since I have owned my Moggy (approx. 18 mos.) I had thought it was running rich. Both a local club member and myself, at various times, had tried to get a nice smooth tick-over and latte coloured plugs....but without success.

On the recommendation of a neighbour (note: UK spelling :D ) I used a local garage and asked the boss/owner to see what he could do and to give the car a general tune up (I still refer to it as a Crypton tune). He rang me later in the day and told me it was all sorted and the car was ready to collect. It seems that the jet was not 'seated correctly' and therefore, as I had found, it was indeed running rich and just as Nickol described, the mixture could not be correctly set.

The car is ticking over like a sewing machine now and running beautifully and not spitting out black sooty water on first start-up. I'm still not entirely sure what not being 'seated correctly' means but it sounds suspiciously like the same problem described by Nickol and B/free.

The moral of my tale, were there to be one, is to get this problem sorted and you'll be amazed at the difference......and also, in my case, get someone in who knows what they are doing :oops:
Bornfree
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Re: Jet head sticking on HS2 Carb

Post by Bornfree »

Thanks, spot on. Disconnect the choke cable, once I’d found small enough scanners, and it was the jet head not moving smoothly. A bit of engine oil, and was much better, then reconnected choke cable, bonnet closed. Just been for a 15 minute run and it was fabulous. Not bad for a car that’d been in a garage for 3 years!!
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