do you need a fuel return line with a weber carb? (1 Viewer)

[gettocruiser]

howdy,

thanks to anyone who has tryied to help me with this, mud has saved me from breaking down and having to thing towed to a shop.

got my 40 officially running today.
run great after it warmed up.
i was alittle afraid i had gotten taken on the spare engine i bought, so i did a comp. check.
125-128 on all six cylinders, i'm happy with that. haven't done a valve adjustment yet...


anyway the old farmer that i bought the truck from had something haywired together for a fuel return from the carb.
i have forgotten what was there after swapping the engine.

just wondering what other guys have done.
i just have the fuel line from the pump on the line-in for the flot bowl. when i pulled the plugs they were fairly black with carbon(running rich). i wonder if i need to run a fuel return to correct this.
the truck also only ran for maybe an hour, mostly at idle so i might be crazy to expect the new plugs to be tan.

also after it warmed up i took for a drive down the alley, it worked great , but if i gave it most of full throttle it would produce a loud back fire, almost everytime. again wondering if it might suggest the need for a fuel return.

thanks, i know this must sound longwinded. i don't want to leave anything out that might be pertinent.

sorry to anyone that had trouble translating this from canadian.
lol
eric

 

[ranger]

Don't need a return fuel line, but you will need a fuel regulator.

 

[ghostriders]

Fuel regulator seems to be debateable. Some use them some don't. I first tried mine with a regulator for about 1000 miles. Then took it off and had no difference in power, stalling or gas milage.

 

[gettocruiser]

i just had another idea...
the engine is a u.s. model 2f and the dizzy is a non-u.s. with a weber on it could the valve adjustment be responsible?
i'll adjust them tomorrow regardless.
hope i'm not chasing a vacume leak...
did i read on here that you can use carb cleaner(?) to locate a vacume leak, is this right?
thanks,
eric

 

[flash02]

As said you don't need a fuel return line. Webbers are somewhat picky about fuel pressure, I think about 3 psi and you may want to check into this. I am not a big fan of Webbers on TLC’s, they will return very poor mpg's and from what I hear have some off road issues. The original Aisin Carburetors are very good carbs, properly tuned they will yield ok mpg’s (14-16 mpg) and will operate very well off road. I have a Webber on a VW engine and that dam thing ran me around in circles with jet sizes; finally with the proper main jet it works great. One thing I learned about Webber carbs is that they operate on there idle circuit until the RPM's are around 1800. (This may differ from other Webbers) My Aisin on the other hand has performed fantastic, adjust it and forget about it, one could eat off my plugs. Dry Black deposits on you plugs indicate a rich fuel mixture, you need to adjust you carb to fix this condition. Adjusting your valves is a good thing but will not prevent your plugs from fouling, with compression numbers like yours I would say your valves are good to go. If you do go for the valve adjustment make sure the engine is at proper operating temperature and you may want to have a new valve cover gasket or some permatex on hand.

Good Luck!

Corey