w460 230g fuel system return line
I posted this question in another forum but nobody is biting. I should have posted it here first!...
The fuel sending unit in my 230g’s fuel tank has two hose nipples (one for fuel out, one for fuel in). Because of a past weber conversion, my truck is no longer running any kind of vapor separator, so there is no longer a fuel return line running back to the tank.
I honestly can’t tell you how it was before I ripped it out because I’ve never seen such a hacked together bundle of mess in my life. The hard lines crumbled in my hands, and both rubber and cloth-covered hoses were spliced together again and again. So basically I have no clean-sheet starting point to reference.
Should I cap off the nipple where the original fuel return line used to connect, should I just leave it open, or do I need to put some sort of one-way valve on it?
Thanks as always in advance!
-Rob
I'm not very familiar with the 230g, having only worked on one once a long time ago (mine is the later injection system where the fuel is taken from the bottom of the tank) but I think the system used to be that there was an overflow/vapour line back to the tank.
Presumably you have a low pressure pump feeding the weber and if the carb doesn't have/need any kind of return then just cap off the spare pipe on the sender.
Just be careful the spare outlet isn't a breather - if it is it should link to the filler neck.
You need to check that you have a vent of some sort. At least to allow air into the tank to replace the fuel volume, otherwise the vacuum will stop fuel flow. You can do this with a vented fuel cap. Or maybe you can't get a vented cap because of emissions rules. In that case a one way valve on the spare tank nipple.
It's been a long time since I owned a carburettor
Having slept on this - if you have 2 nipples on the sender unit and one was a return it will probably empty into the tank high up. The feed pipe will go all the way to the bottom of the sender - you will obviously need this one for your feed.
Hi could be someone has fitted a diesel fuel tank which has a sender with two pipes... one feed and one return....the vent pipe is on the top of the diesel tank and is remote from the sender....the petrol tank sender has an electrical connection only with the primary fuel supply outlet pipe welded into the top of the tank 5 cm away from the sender.I have just done a "visual" of the two petrol tanks and one diesel tank we have in stock..
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Thanks dentsmithy! I believe you are absolutely right on your analysis of my setup. I don't think the spare pipe is a breather, and I think it was originally intended for the return line. I followed the routing of hoses as laid out in an image from the russian epc site.
The filler neck has two nipples. The tank has two nipples. And the sender unit in the top of the tank has two nipples. I ran one 1/2" hose from a filler neck nipple to one on the center top of the tank. I ran one 1/4" hose from the other filler neck nipple to the other tank nipple on the far left side. Then I ran a 5/16 hose from one fuel sender unit nipple to the fuel pump. It appears that the sender unit in the epc image has only one hose coming out of it, but I have two. Its this final sender unit nipple that has me stumped.
I think I may just cap it off and see how she runs. Thanks again!