Still bloody fibre-glassing!!
Today I managed to make some protectors for the pilot jets. The recess the jets sit in is more than 7.5mm diameter and the jet is about 7 to 8mm recessed. I toyed with a couple of ideas, a 3mm mini rawl bolt with an “O” ring that would compress against the walls of the recess (too difficult to make and not enough available depth), a cast plug made from silicone sealer (no improvement over the original rubber bungs)
I settled on tapping the recess 8mm, it was not possible to put the right size drill down there as I would have damaged the pilot jets but because the carburettor is comparatively soft I got away with starting a plug tap which had about a two thread lead in. So I cut one complete thread in each recess and then ground the lead in off the plug tap and managed to get 3 or 4 full threads before the tap hit the jet. Then I turned up some 10mm hexagon bar, threaded it 8mm and added a couple of 8mm ID “O” rings. Jobs a good un.
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