A15 carburettor problems

[rbastedo]

I've got the econo head on my A15 and the Hitachi carb - not sure if it's the dch-306 or the dch-340.

It's old and worn out, and does some strange stuff.

I converted to manual choke, I guess just because I'm a control freak.

Here's the strangest thing it does:

Adjusting the jet:
It's got this tube with a screw inside. Doing this while the engine is running I put my screwdriver in there and turn and sometimes I see a small spark inside and when this happens the engine stumbles.

WTH can cause that???

Couple pics of my carb as it sits now.

[paradoxx]

when you are adjusting the jet, do you have the engine running or the switch on the ignition position? if this is the case you have a spark failure that can cause a fire there! take a look at you cables and coil wiring.

[rbastedo]

Originally Posted by paradoxx

when you are adjusting the jet, do you have the engine running or the switch on the ignition position? if this is the case you have a spark failure that can cause a fire there! take a look at you cables and coil wiring.

Yes, adjusting with the engine running. Getting an arc between the screw and the screwdriver and the little "tube" passageway the screw is set into.
When this happens the engine stumbles.

Very strange!!

[paradoxx]

so your spark is going to ground, Check your spark wires or the condenser on the dizzy.

[rbastedo]

You are thinking somehow the spark from the ignition system is making it over to the carb and arcing from the jet adjustment screw??

I'm not seeing it.

FWIW I just replaced cap, rotor, wires and plugs.

[rbastedo]

I pulled the solenoid and found the red wire broken near the base of the unit.
Barely enough there to make a repair, but I did it and put it back in.
No more sparking and no more dieseling.
Sometimes it is just that simple.