1'8th monobloc on 1954 G80s

[TommoT]

Hi,
it has got to be a fault in the float chamber. Maybe the float needle is prevented from closing due to incorrect float level. Try to check the level either by fitting a clear float chamber end cover or by using an old main jet cover nut fitted with a clear plastic tube. The level should be adjusted to coincide with embossed dot on the cover. Also check that the tickler is not permanently engaged.

Good luck!

Regards,
Tom M.

[RogerNorman]

The flat on the float that the float needle engages are prone to wearing flat over time. This will have the same effect described of flooding the carb. You are best off to replace the float but you can carefully fill with solder. Its also worth checking the float needle itself. I recently had to replace one which had distorted and was sticking in the float tower where the feed pipe banjo bolt connects on the carb. Make sure also that you have the correct fibre washers in the right place. An extra one can raise the height just enough to cause flooding.