Fuel Return Line - None Fitted

[BlowingOldBoots]

On my engine, Perkins 4236, there is no fuel return line. There used to be one but a long time ago new fuel lines, new twin fuel filter and repositioning of filter was all preformed. I have twin fuel tanks and both tanks have what I assume are the old fuel return lines still fitted, but with the ends closed off and not connected to anything.

I currently have one tank decommissioned as i don't need that amount of fuel onboard and one in use. I have used this arrangement for over a decade now and the engine has been bled since and it all works as expected.

I have read a comment on another site that talks about fuel cooling and even over pressuring fuel lines from the high pressure injector pump. I am looking for an explanation on the return fuel line and is this something that I should reinstate. If I was to reinstate this, where is the return line taken from.

Alastair

[cpedw]

I'm not an expert and I've never understood why diesel engines have fuel return - why not just send enough fuel?

But all the engines that I have known have returned fuel via a pipe connecting all the injetors together. I think this is the vital part that should be connected to the fuel return line.

Derek

[bosun]

I look aftre a boat with a Petkins 4-236. It too has no return pipe; however, the return goes to a spare input on the CAV fuel filter.
Seems to work OK.

[BlowingOldBoots]

Thanks for the link Derek and the observation Bosun. I’ll check to see if mine is perhaps linked to the final filter on the engine, which is a CAV. Perhaps that link is there and I have just not recognised it. In my research I did come across a description that stated the fuel return can be connected to a filter.