Author Topic: Leaking pre-monobloc  (Read 2450 times)

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Offline alexd912

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Leaking pre-monobloc
« on: 16 Sep 2014 at 04:47 »
Hi there,

I have a leaking union on my pre-monobloc 274 carb when I tickle it.

Is this normal practice?

It does seem to stop once the engine has started.

Also does any one have any tips on Needle valve height and mixture screw.
Engine is 600 OHV single carb

Thanks

Alex
Best regards
Alex
1930 Douglas G31

Offline eddie

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Re: Leaking pre-monobloc
« Reply #1 on: 16 Sep 2014 at 06:37 »
Alex,
        Your carb is not 'leaking' - there is normally a bleed hole at the side of the choke block and fuel will spill from it if the level is artificially raised by tickling the carb.
      When you refer to the needle valve, I presume you mean the float needle - there is not normally any provision for adjusting the float height. Regarding the mixture screw - this should be wound fully in, and then backed off about 2 - 2 turns to obtain a steady tickover along with good response to the throttle.

        Regards,
                     Eddie.

Offline RockDr.

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Re: Leaking pre-monobloc
« Reply #2 on: 16 Sep 2014 at 11:04 »

Offline alexd912

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Re: Leaking pre-monobloc
« Reply #3 on: 16 Sep 2014 at 11:19 »
hey there,

Thanks for this.. there are good instructions for the needle (That was what I meant, sorry).

So I should take that awful sealant of my carb.. I had replaced the seal there, but has its norm I'm happy now.

The engine runs great at the moment, only problem I have now is the damn clutch.
It feels like it is sticking/slipping..
It seems a real art to get that right..
I'm starting to think I will put a spring on the clutch cable to help force the leaver (on the flywheel side) to help out.
Also I think I need to tighten the clutch plate nut.

Its quite strange as sometimes it will kick over perfectly, another time it wont spin the flywheel.

Also another strange thing I had was that the magneto was rebuilt and the cam and cam housing (with advance retard assembly) was replaced to what appears to be in the original press release photos. But the bike would start to run on one cylinder and spit fuel out of the carb.
I then decided to put the original one that came with the bike then it sprung into life:)
Im just wondering if there is anyway to replace the cam (sorry not sure what the correct name is) from one housing to another?
At the moment the current cam housing is just help in place with the front plate spring/pressure arm on the front of the mag.

Sorry for all the questions...

Alex
Best regards
Alex
1930 Douglas G31