WJ/WG CRD Fuel Filters
 

Hi people,
I am having a bit of trouble starting my GC after sitting, I think there is air getting into the system, I have also bought a GC from the auctions with a bent
diff, thing is this one starts first time, every time no matter how long it sits.
Here is the twist, hard starter has a original fuel filter = Z670, easy starter has
a Z694 as fitted to merc ml270, noting this filter doesn't have the fuel return
valve.
So has anyone else seen this filter fitted? is it detrimental to the fuel system
not having a return off the filter?
Cheers John

I had the same problem with mine, I put a new filter on and it wouldn't start no matter what we tried , so put the old one back on and started first go

Grandpa, were they the same filters? I have 2 new MB filters here in boxes but they
need the return valve...

Shouldn't be a problem, I'm running a Z670 in mine at the moment but have had the fuel return bypassed for ages, the O ring on the filter fuel line is probably the cause, it's a trial and error method that will locate the cause for you as it can be a number of things from dud O rings to a small crack in the rubber fuel line.

Just make sure the return line from the rail goes to the line to the tank don't block it off.

Thanks Drover, will make sure I don't block off the return..

exact same filter

On my filter I have blocked the return unit on the filter and just plumbed the return line straight to the tank.