Jap 34 cc engine

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Series3boy
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Jap 34 cc engine

My qualcast powered panther has a Jap 34 cc engine it recomends a 1 :32 mix. It is struggling to start on that so tried 1:40 with some triubelmit did start.

I have heard that you should used less oil when using modern 2 stroke oil. 

 

Any thoughts on this would be welcome.

wristpin
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For a vintage engine with

For a vintage engine with fairly rudimentary crank case sealing  it is recommended that you use a straight SAE 30 or 40  non detergent motor oil or even better the vintage two stroke oils marketed by Millers or Morris lubricants and others. Modern semi or fully synthetic mixing oils are not recommended.

Two possibilities re the stalling. Dirt in the fuel system restricting the fuel flow or an adjustable metering needle in the carb, set too week. Post an image of the carburettor.

Series3boy
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Thank you

Thank you

The carburettor is an Amal 360/s similar to the later 308.

The needle was set to the lowest position so a weak mixture.

The engine seems to be flooding as I am getting a wet plug and the engine will not start.

I have contacted Meetens who are hopefully sending me a need needle and seat etc. Do you think that might be the issue? Or could it be the float?

Any help appreciated.

wristpin
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Give the float a shake and

Give the float a shake and listen for anything sloshing round inside. Then hold the float down in a pan of just boiled water. This will expand the air within the float and you will see a stream of bubbles from any leak. If those tests are negative you can assume that it is serviceable.

I'm not familiar with the carbs that you mention  - but they look to be of the Amal type that have a screw in brass seat with a needle with a cone shaped end that is pulled up into the seat by the float. If the cone is not sealing into the seat you can try lapping it to the seat using a metal polish such as Brasso. Sometimes it works, other times it doesn't. Meetens probably have needles and seats. 

Are we to assume that th spark is good and at the right time? If not the flooding could be down to mixture being sucked in but not ignited rather than the spark being extinguished by an excess of fuel.