Petrol engines aircooled - Fuel Leaks

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Twin Solexes - Carb fuel feed stub-pipe comes loose

Typical story

IrishKeet: Went to Wales last weekend and we ran out of LPG so I switched to petrol, after a few mins we had a strong smell of petrol and the van lost most of the power, we broke down at the tool booth on the Severn Bridge! I managed to start it again and we limped to the side of the road.

Got my partner to start up the van and petrol was pouring over the right exchanger and onto the road, after looking in the engine I noticed that the fuel line had come undone (photos below)


mrhutch: On standard twin Solexes your fuel line should come in at the right hand side of the rear bulkhead, and split on a T piece to each carb. But... the LHS carb controls the idling mix and fuelling to the RHS Carb (supplied by metal pipe running along back bulkhead)

I think the piece that popped off for you is the main fuel line INTO the RHS carb (i.e. part of the carb itself). I've never seen this part of the carb fail before, and it is quite worrying.

HarryMann: With the known history of fuel-related fires on VW buses - Very worrying!


A careful cleanup with fine wet-dry paper, removing any corrosion from both carb and pipe, degrease and then selecting a suitable fuel-proof adhesive (Loctite probably), then tapping it in with a block of wood. Yes, its either an interference fit or a slight taper, maybe even chilled and tapped in. Body of carb will be a zinc-based casting alloy, so in theory could be brazed/soldered (but only with the right flux!) Another type of sealant that [i]might work would be an RTV silicone sealant [/i]

The other belt'n'braces trick would be to mechanically secure the attached feed pipe to the carb, so if the pipe does work loose, it wouldn't come right out.

Re-attach fuel hose to pipe using proper fuel-hose clips (the correct size for hose/pipe using a small nut & bolt to secure, ''NOT small Jubilee clips)

Check, re-inspect at regular intervals

If you run dual-fuel, always check the switch-over to petrol before leaving for a long journey where you might need to use the petrol.



Various companies rebuild carburrettors. A check on the fuel-feed stub-pipe should be a part of this service. Often a carb is sent for refurb/rebuild when the butterfly spindle bushes develop wear and air-leaks which upsets idling performance, or requires stripping to clean blocked jets or other contaminants.