Dellorto PHBN 14 Main Jet problem


New Member
Hi there

I am having a problem with the main jet of my Dellorto PHBN14.
It's a new carb on and Aerox 50 as the old one was worn and had a leaky float chamber.
I unscrewed the main jet with was an 88 and screwed the 95 I had in the kit of 6mm jets I bought.
Now the jet only threads in about one turn and doesnt screw down flush to the main jet tower like the original does, even the original one has the same problem since I removed it. The primary emulsion tube is sticking up too much.
Is there a certain way the primary tube needs to be mounted to give enough room for the main jet to screw in proud with the tower? am I doing something else wrong?

Any help would be most appreciated,

Tom from Perth, Western Australia.
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Broem Broem Pff Pff
Are you sure you have bought the right size mainjet.. There seems to be smaller en bigger ones available. If you screw in the wrong one, you could accendently damage the threads on the main jet tube.


New Member
Thanks, I fixed the problem anyway, I just drilled the inner emulsion tube rest down a couple of mm and ground some material of off the surface on the tube that the needle rests on. And now it's perfect. Contacted Dellorto UK and they said it should sit proud of the tower 2mm or so anyway..
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