Fuel system cleaner


Well-Known Member
My P6b had a carb overhaul a year back and she is still running as sweat as ever.
I know our older motors don't like the new bio-fuels, well the fuel system don't.
My question is .
Is it OK to use a fuel system cleaner to maintain this carbie performance.
I can't find any reference to these cleaners hurting our older systems, like bio-fuels do.
Anyone have a preferred brand they use on their V8



Well-Known Member
I have used stuff labelled as fuel injection system cleaners a few times, mostly as a just-in-case thing. Most injection systems have a pressure regulator in the pipes, with the unused fuel recirculating back to the tank. In the case of my 928 (CIS injection, at 75psi) which had stood unused for some time, I added some cleaner stuff to the tank, and left the pump running for over an hour to try to scour deposits into the filter. Seemed to work, every thing worked as it should. many recommend doing an oil change soon after using a fuel additive as its likely to get past the rings into the sump. A fuel filter change would also be a good idea.
I dont know that our return system will flow enough to be useful for this process - the rate at which my electric pump works says the volume is very low.
I would add some cleaner to a full tank, use most of it up, refill, replace the fuel filter and do an oil change.