Fuel Return Line Fitting??

[Stan]

Below is a pic of my fuel return line.  It goes from the small upper pipe on the injector back to the upper portion of the fuel tank.  The fitting in the middle is hopelessly clogged up, and with judicious and very gentle feeling around in there with a plastic pick, it seems as if there's a ball shaped object in there.  Could that be a non-return ball valve that is steel and has become very rusted and stuck?  If so is this a manditory part?  Will it run satisfactorily without it or is it something I have to start sourcing because I don't think it's going to be salvageable.
Stan

[listerdiesel]

Never seen that before on a leak-off pipe, but it does look reasonably original.

All early CS engines had a pipe running into a small can on the side of the engine which clipped onto a small bracket. This little can and lid is quite rare to see nowadays, but I have one as a reference if anyone needs dimensions to make their engine original.

Later engines had a pipe running into a hole in the fuel tank with no union, and then at last a proper union connection was provided towards the end.

I'll check the changed numbers listing to see if anything is mentioned.

Peter

[Flyingpony]

All early CS engines had a pipe running into a small can on the side of the engine which clipped onto a small bracket. This little can and lid is quite rare to see nowadays, but I have one as a reference if anyone needs dimensions to make their engine original.

Rare you say, huh.  Got one of them on the 3/1.

Quite good till you forget to empty it before each start ... they'll then overflow and drip onto the rotating flywheel beneath ... I'll leave the rest to your imagination 

Right now, the pipe has had a length of white plastic tubing added to it and this flows into a 20l drum.  Now it's simply a matter of once a month to empty this overflow drum into the main tank.

[Stan]

OK so it sounds like  if I just replace this gummed up fitting with a single long piece of plain copper piping that leads back to the top of the fuel tank, it'll just keep dripping away back inside the tank where it's supposed to be?  Right?  Just because there was once a non-return?? valve in the line is no reason to suppose there has to be one there now.  Right?
Stan

[listerdiesel]

Rare you say, huh.  Got one of them on the 3/1.

Yes, you won't see many now as most were lost off the engines, leaving just the bracket.

Quite good till you forget to empty it before each start ... they'll then overflow and drip onto the rotating flywheel beneath ... I'll leave the rest to your imagination 

Can be quite messy, but a good injector shouldn't be spilling that much diesel out in the first place.

Right now, the pipe has had a length of white plastic tubing added to it and this flows into a 20l drum.  Now it's simply a matter of once a month to empty this overflow drum into the main tank.

Can you route that directly back to the fuel tank?

Peter

[listerdiesel]

OK so it sounds like  if I just replace this gummed up fitting with a single long piece of plain copper piping that leads back to the top of the fuel tank, it'll just keep dripping away back inside the tank where it's supposed to be?  Right?  Just because there was once a non-return?? valve in the line is no reason to suppose there has to be one there now.  Right?
Stan

It does in fact come up in the Changed Numbers list.

Engines from number 125 up to 60346, Spec 10 onwards, had the drip can 5-1/C79

Spec 208-13 from 60347 up to engine number 85639 had a non-return valve part number 10-7-145 and this was for tank-cooled engines only.

After that a plain pipe was fitted that went to the fuel tank.

Peter

[rcavictim]

My Petter PJ-1 came with a rubber fuel return from the injector bypass output to a bushing at the top of the fuel tank.  I have done the same on my newly fabricated power plant in which this engine is now installed.  The return flow just goes drip, drip, drip inside the tank.  Works great.

I also have a fuel return to tank from the injector on my JD175A engine.  It was a cheap clear vinyl type plastic hose that if disconnected at the injector end would drain the fuel tank to some level less than full of the tank was full, not good.  Problem is the return enters the fuel tank too far down the sie, not at the top.  I replaced the cheap line with a good automotive rubber line, 1/4 inch ID.

When I made the VW plant from a 1980 Rabbit diesel 1.5L NA engine I ran the fuel return from the injector pump to a bushing at the very top of the fuel tank.  Can`t seem to recall just now where the overflow manifold hose system on the injectors goes, maybe a port on the injection pump associated with the return discharge to the tank.

Stan, just run a line to drip into the very top of your fuel tank with no drainback valve.  Don`t have the end of the line dipped in the fuel or you could create a siphon drain like my JD came with if the line ever comes off the injector or something.

[Stan]

That's why mine has the nonreturn valve on it, because the return line goes back in to the fuel tank about 2" below the top.  Maybe I'll look around to see if I can find one like it.
Stan

[Flyingpony]

Quite good till you forget to empty it before each start ... they'll then overflow and drip onto the rotating flywheel beneath ... I'll leave the rest to your imagination 

Can be quite messy, but a good injector shouldn't be spilling that much diesel out in the first place.

This was quite sometime back, it took quite a number of run time hours before the cup over flowed - maybe 50hrs.
Did attempt to get into the habit of emptying it frequently but obviously that didn't always work.  In the end I gave up and fixed it as self-quoted below.

Right now, the pipe has had a length of white plastic tubing added to it and this flows into a 20l drum.  Now it's simply a matter of once a month to empty this overflow drum into the main tank.

Can you route that directly back to the fuel tank?

Given the original cup was beneath the injector level, I thought this pipe was gravity powered and therefore it never occurred to me to reroute this some 30cm higher than the engine into the fuel tank.  Have recently looked at the Indian Listers, but their tanks aren't any higher than the engine height, so I probably stay with status-quota but this is food for thought, Thanks.

[listerdiesel]

Have recently looked at the Indian Listers, but their tanks aren't any higher than the engine height, so I probably stay with status-quo but this is food for thought, Thanks.

It will push uphill with no problem, just make sure the injector end is fuel tight as it will stand with fuel in the pipe.

Peter

[Stan]

Got it "loosened up" somewhat.  I feels like there's a ball inside (haven't the foggiest notion of how they get it in there???) with a small spring to keep it "closed".  It moves with the barest of pressure from the little plastic pipe you find on an aerosal can.  it won't move by itself however and I think it's supposed to.  The spring must have been steel and has rusted into oblivion.  I'll keep soaking it in gunk and see if it will be magically restored.
Stan