Question : whats the best way to clean dirty fuel?

[Sanderson]

Question : whats the best way to clean dirty fuel.... I think that's what's stopping from my car wanting to turn over every time... My new sparks are dirty already... due to this

[sim16v]

Drain the tank, put fresh fuel in and a fresh filter.

I bought an M3 that stood for 5 years.

I put a new pump in and it wouldn't start, drained the tank dry and put fresh in.

Started first time.

[Classic Grad 98]

Dirty fuel won't stop a car turning over.

[v8250]

sanderson, your sparkplugs will not be 'dirty' due to 'dirty fuel'. they'll be dirty because of combustion and most likely due to air-fuel mixture not being correct.

IMHO don't faff around with 'dirty fuel' [if infact it is dirty]. safely dispose of old 'varnished' fuel, clean tank with tank cleaner and fuel lines, fit new fuel filter before fuel pump, clean fuel pump [if this is an old SU it could be full of crap] and rebuild correctly, fit inline filter before carbs/injectors making sure it's capacity [fuel flow rate] is correct. if on carbs set these up. then providing ignition timing is correct and engine isn't knackered, all will be well. good luck.

[v8250]

have just read your MKII thread. is it the jaguar that's got dirty fuel? if so, really do clean the complete fuel supply from tank right through to SU carbs + check SU float chambers as they are always forgotten about and can be full of muck. whilst apart be sure to reset float chamber settings before re-assembly. then check jet-to-deck heights, needle position, clean SU pistons, check piston springs, oil in dashpots etc, then set-up SU's with air meter. you may want to buy a rebuild kit from burlen fuels. same goes for your mgb gt; both have similar SU components.