Four stroke asp 120 issue resolved

Some of you may have noticed for Many weeks now I’ve been trying to get the four stroke on a hanger 9 spitfire to idle and run without the glow starter attached. Many painful hours at home running up in the garden and frustrations up at the field with no joy adjusting low needle etc.

However whilst I was packing up on Sunday at Cashmoor Phil Ford said in the past he had had to raise the fuel supply line above the tank before going down into the carb nipple as it was siphoning fuel into the engine, the engine is mounted up side down and carb nipple facing downwards. So tonight I got a longer fuel tube and did just that. Within 10 mins of adjusting the low end needle I had the motor nicely idling and great pick up with throttle increases.

Just need to hope it’s still behaves when I next visit Cashmoor.

Thought you all should know in case anyone else has an issue.

Well done phil, thanks for the advice! And thanks all who have been trying hard to get it going the last few weeks.

Nice one Dave.

Good to see what can be achieved when great minds come together

Glad you've got it sorted Dave. If you'd asked me I would have suggested crap in the carb

Magic stuff Dave. :woohoo: Just got to wait for some decent weather in the future. Keep us posted - video camera ready.

I had a similar issue with the ME109 and solved it with that hack. The thing is it takes a bit longer to bring the fuel up from a cold start but once fuel is on the glow it's away.

Dave Rogers wrote: Some of you may have noticed for Many weeks now I’ve been trying to get the four stroke on a hanger 9 spitfire to idle and run without the glow starter attached. Many painful hours at home running up in the garden and frustrations up at the field with no joy adjusting low needle etc.

However whilst I was packing up on Sunday at Cashmoor Phil Ford said in the past he had had to raise the fuel supply line above the tank before going down into the carb nipple as it was siphoning fuel into the engine, the engine is mounted up side down and carb nipple facing downwards. So tonight I got a longer fuel tube and did just that. Within 10 mins of adjusting the low end needle I had the motor nicely idling and great pick up with throttle increases.

Just need to hope it’s still behaves when I next visit Cashmoor.

]

Great news Dave and because i came home stinking of its glow fuel, I'm interested in the theory. I think its more correct to say that prior to the change the fuel was flooding the carb by gravity. Now the carb has to work harder to assist syphoning the fuel via this high loop. This is very strange as all attempts to richen and weakening the idle mixture made no difference. - Are you saying this s the ONLY work / change since Sunday. ?

Only thing I did, yes Kevin. it ran so much better, then I fiddled with the low needle until it was purring at idle. Job done.

Sorry to hear of you smelling on my account.

Dave may I suggest that you use a small cable P clamp to secure the pipe. I know it won't be seen when the cowl is on but it will look aesthetically better for those who will no doubt take advantage and take the p**s if they view it with cowl off. :lol:

You know how long the "maybug" lasted.....

Dave - Just a thought, have you considered further tests at home, with the model in various attitudes i.e nose up, inverted etc ?
I'm sure Kevin will enjoy the aroma of burnt glo fuel as it permiates his clothing.
So far there have been no reports of spent electrons having the same effect.

Colin

JonTappin wrote: Nice one Dave.

Good to see what can be achieved when great minds come together

Who's was the second mind? I acknowledge Phil has the first in this instance.....struggling to see the other...........:huh:

davidbright wrote:

JonTappin wrote: Nice one Dave.

Good to see what can be achieved when great minds come together

Who's was the second mind? I acknowledge Phil has the first in this instance.....struggling to see the other...........:huh:

I am struggling too......:S

I refer back to my post mentioning the ME109. This was how I stopped the syphoning effect. The carb needle is below the bottom of the tank so syphoning is likely. Alternatively mount the engine sideways on, four strokes are taller due the valve gear - Ugh! Cylinder sticking out of side of cowl.

Anyway all's well now according to Dave (he said with fingers crossed)