Strange output from fuel filter to bottle.

[pete.i]

I've been studying my boat engine today, as you do. It's a Beta Marine 34/38 according to the booklet I have. There is a rubber fuel pipe that ends up going to a plastic bottle jammed in by the side of the engine. It comes out of the top of the fuel filter but is offset from the filter input so this must be the fuel filter out line. It then goes to a "oojimaflip" and presumably from that to the high pressure fuel pump. But coming out of the side of the "oojimaflip" is a pipe that is connected to a rubber fuel pipe, it's marked as such, and this pipe goes to a container, that is quite obviously, not part of the original build. 

 

Can anyone tell me what the purpose of the pipe coming from the side of the "oojimaflip" is for and why it goes to a random bottle rather than back to the fuel tank as the diesel leak off pipe does. Also can somebody name or tell me the purpose of the 2oojimaflip" please. I've included some pics to, hopefully, make my questions a bit clearer. Thank you.

 

[matty40s]

Bottle use..

Perhaps for when draining down the fuel from your systems lowest point without getting it all over your engine bay.

 

 

edited to add, although as others point out - no tap...

Edited September 1, 2019 by matty40s

[pete.i]

Okay I can see that, but there is no tap that I can see in that circuit but the bottle has never had anything in it. I will admit that as the pipe is buried at the front and side of the engine it is difficult to see the complete run. Thanks for the reply though.

 

Ah the "oojimaflip" is the lift pump. I cannot see a lever on it to operate it manually when bleeding the system but as I said it isn't in an easy to see position so I assume it is there and therefore that pipe going to the bottle must be to catch any diesel as Matty40s has said. I still cannot see a tap though to isolate that bleed off point, if that is what it is.

Edited September 1, 2019 by pete.i

[BEngo]

If the oojymaflip is a lift pump, and it does look a bit like one, there must be a third pipe from it that is not shown in the pics.

On that basis I think the mystery pipe might be a vent, which stops crankcase pressure from holding the pump diaphragm in the up position against the spring. Someone has extended it to a bottle to catch the odd drips of oil which come with crankcase vapours.  It may even have originally been connected to the airfilter housing or the air inlet pipery.

Otherwise it is perhaps a drain off so that a diaphragm  split or other leak cannot allow diesel into the sump and cause a runaway or wreck the bearings from diluted oil.

 

If the bottle is not filling up there ain't  a problem IMO.

N

[pete.i]

Nope no problem I just like to know what things are.

[dor]

Are you sure it is an oojymaflip?  Looks more like a thingumabob to me.

[Tony Brooks]

For comments, could the pipe in the bottle be a crankcase breather?

[pete.i]

This is the picture from the Beta Marine parts list and the oojimaflip is labelled as the lift pump. The pipe that I have arrowed appears to connect to the bottom of the sump oil removal pump but it actually connects to a small pipe on the back of the fuel lift pump. As you can see it goes to a brass connector at the back end of the engine and on my engine, which is green, the other side of that connector has a rubber pipe marked fuel that goes into a bottle. I can understand it being a bleed off for when the lift pump is manually pumped although I cannot see a manual lever, but the lift pump is in an awkward position. But if it's a bleed line I would have though there would have been some sort of tap or valve to isolate that pipe which, again, I cannot see.