Posted: 02 Feb 2007 06:42 pm
Let me try to clear it up a little.
Most carb-powered cars have a single fuel line from the tank to the carb. 300s are a bit wierd, in that they have two lines - send and return, like a injection car. Why? I have no idea.
Injection cars need a return line because the fuel is 'circulated' under high pressure, while carb pumps run much lower pressure, so it's safe for the pressurised fuel from the pump to be 'piled on top of' that already in the lines. I believe there may be a heat issue involved, as well as implications for the lifespan of the pump. I'm not that clear on this, but certainly the default for carb setups is 'no return'. My 360 is now plumbed like this (because of the twin carb setup), with the return line blocked off.
IIRC, the return line is handled by the pump on a B14, but on the B200K and 1.7 cars, there is this vapour separator which does this job. It has three connnections:
Fuel in (from pump)
Fuel out (to carb)
Excess fuel out (back to tank)
I'm very confident that this isn't a filter, and doesn't need replacing like a filter. It wouldn't be a surprise if it were referred to as a filter, as that's what it would be on most cars...and it looks like (a wierd) one!
cheers
James
Most carb-powered cars have a single fuel line from the tank to the carb. 300s are a bit wierd, in that they have two lines - send and return, like a injection car. Why? I have no idea.
Injection cars need a return line because the fuel is 'circulated' under high pressure, while carb pumps run much lower pressure, so it's safe for the pressurised fuel from the pump to be 'piled on top of' that already in the lines. I believe there may be a heat issue involved, as well as implications for the lifespan of the pump. I'm not that clear on this, but certainly the default for carb setups is 'no return'. My 360 is now plumbed like this (because of the twin carb setup), with the return line blocked off.
IIRC, the return line is handled by the pump on a B14, but on the B200K and 1.7 cars, there is this vapour separator which does this job. It has three connnections:
Fuel in (from pump)
Fuel out (to carb)
Excess fuel out (back to tank)
I'm very confident that this isn't a filter, and doesn't need replacing like a filter. It wouldn't be a surprise if it were referred to as a filter, as that's what it would be on most cars...and it looks like (a wierd) one!
cheers
James

