Intermittent Fuel Leak

[ColinFesterBesterTester]

Hoping someone can suggest cause of a carb fuel leak. I started the car from cold last Friday (warm day but car in garage), and saw fuel dripping/dribbling from the off-side Stromberg. The car had stood for several weeks prior to this. The engine was idling fine (with a small amount of choke whilst warming-up), not lumpy or stuttering at all. For safety however I switched-off engine and pushed back into the garage. It looked like the fuel may have been from the cap at the base of the carb, but hard to be sure that fuel was leaking from here. 2 days later (before starting to strip it down) I started the engine again, and could not detect any leak - definitely not dribbling like before. I had another look this evening, everything cold, and the cap did seem a little moist from fuel. Any thoughts on why there was a significant leak on Friday, yet next to nothing yesterday? It is possible that the cap has had a slow weep for some time and gone un-noticed, with the significant leak being something else/a new second source of fuel. Could the O-Ring have dried-out and shrunk causing a leak, then swelling again once immersed in fuel, sealing the joint (apart from slight seepage)? Any thoughts welcome, and best place for Stromberg spares.

[DJT]

Sounds like new o-ring would be a good move. Best place for Stromberg spares is www.burlen.co.uk

[wilf]

I would replace the cap itself, too, as they can harden with age - on both carbs. Again from Burlen.

[richardthestag]

+1 for burlen.co.uk

Well worth checking fuel pressure also. pumps, especially modern units, push too much pressure for the stag strom setup. malpassi filterking is what many use to regulate the pressure down to 3psi.