Diesel return rail

[Scholar Gypsy]

The metal pipework that takes surplus fuel from the injectors back to the main tank fractured yesterday. I am getting it repaired - by someone who knows how to braze. I will probably buy a replacement part (it's a Mitsubishi K4E) though it will take 6 weeks to get here from Japan (Diamond Diesels don't have one in stock) and cost £60. 

 

My question is whether it is feasible/safe/BSS compliant to assemble a replacement - in case it fractures again -  using standard banjo unions (one single and three doubles) and some short sections of fuel hose and lots of jubilee clips. If so then if anyone knows of a suitable supplier then please let me know. There are lots on e-bay of course .... 

 

Thanks

[Tony Brooks]

46 minutes ago, Scholar Gypsy said:

The metal pipework that takes surplus fuel from the injectors back to the main tank fractured yesterday. I am getting it repaired - by someone who knows how to braze. I will probably buy a replacement part (it's a Mitsubishi K4E) though it will take 6 weeks to get here from Japan (Diamond Diesels don't have one in stock) and cost £60. 

 

My question is whether it is feasible/safe/BSS compliant to assemble a replacement - in case it fractures again -  using standard banjo unions (one single and three doubles) and some short sections of fuel hose and lots of jubilee clips. If so then if anyone knows of a suitable supplier then please let me know. There are lots on e-bay of course .... 

 

Thanks

 

I think nowadays yes, but there are requirements for a cut oft tap at the tank end. To be safe I would ask the BSS office on Monday.

[Scholar Gypsy]

41 minutes ago, Tony Brooks said:

 

I think nowadays yes, but there are requirements for a cut oft tap at the tank end. To be safe I would ask the BSS office on Monday.

Thank you. (at the moment, I have an isolator on the main fuel pipe (tank to pump) but not on the return pipe).

[Keeping Up]

I've never heard of anyone having, or needing, an isolator on the return pipe.

[ditchcrawler]

I thought it was a non return valve.

 

From Boat safety site 

"

Injector leak-off (spill rail) arrangements must meet all the requirements for fuel feed and return pipes, hose and connections, or

• utilise the direct return to tank option, or
• return to the fuel system through a non-return valve.
• injector leak-off hoses fitted by the manufacturer within an enclosure on the engine meet the requirement."
• https://www.boatsafetyscheme.org/boat-examination-and-certification/non-private-boats/part-2-inboard-engines/flexible-hoses/ 
• And
• https://www.boatsafetyscheme.org/boat-examination-and-certification/non-private-boats/part-2-inboard-engines/flexible-hoses/spill-lines-(2002-2007)/

Edited July 13, 2019 by ditchcrawler

[RLWP]

1 minute ago, Keeping Up said:

I've never heard of anyone having, or needing, an isolator on the return pipe.

We have an isolator on our return pipe

[Keeping Up]

1 minute ago, RLWP said:

We have an isolator on our return pipe

Why?

[RLWP]

Just now, Keeping Up said:

Why?

Because I haven't taken it out? It has always been there

 

They are not that unusual

 

Richard

[ditchcrawler]

1 minute ago, RLWP said:

Because I haven't taken it out? It has always been there

 

They are not that unusual

 

Richard

So have I

[Slim]

I would have thought that if the brazing was done by someone who is competent then the repair will last. My spill rail (bmc) is brazed from new. A friend had a problem with a spill rail out in Greece some years ago and as far as I know the repair has held up.

[alan_fincher]

I think the BSS can be very iffy about having flexible sections in a spill rail, even if that was original equipment on the engine.

 

Our Calcutt marinised BMC 1800 in a previous boat had the original BMC vehicular arrangement, and the boat came with much documentation from when it had been failed, but they had successfully argued the case.  At least one BSS under ownership the examiner threatened to fail it, but relented when shown the paperwork.

 

I imagine that just using fuel hose might be considered a no no by some examiners, (ours was at least a complete one piece manufactured part), but admit I have not called up the latest BSS check list to see exactly what it says on the topic.  It's worth doing that, at least, before putting effort into something that might fail a BSS.

[system 4-50]

12 hours ago, RLWP said:

We have an isolator on our return pipe

And me.

(not sure what happens if you have it closed and try to run the engine?)

Edited July 14, 2019 by system 4-50

[RLWP]

2 minutes ago, system 4-50 said:

And me.

(not sure what happens if you have it closed and try to run the engine?)

[system 4-50]

I think I'll add an extra nylon tie around the valve handle.  (I only wear silk ties when boating.)

[RLWP]

31 minutes ago, system 4-50 said:

I think I'll add an extra nylon tie around the valve handle.  (I only wear silk ties when boating.)

I prefer a cravat, myself

[Ray T]

41 minutes ago, RLWP said:

I prefer a cravat, myself

A red one with white spots per chance? 

 

Many moons ago just after we bought the boat, we had a spill rail fracture near the banjo connection, dumped a load of fuel into the bilge.

The cause, the fuel filter bracket had worked loose and caused a fatigue fracture.

Edited July 14, 2019 by Ray T

[Flyboy]

14 hours ago, RLWP said:

We have an isolator on our return pipe

So have I.  Would it be so that you can pressure test the tank easily?

[Scholar Gypsy]

14 hours ago, Slim said:

I would have thought that if the brazing was done by someone who is competent then the repair will last. My spill rail (bmc) is brazed from new. A friend had a problem with a spill rail out in Greece some years ago and as far as I know the repair has held up.

Thanks very much for the comments. I think I will go with this approach, buy a couple of banjo unions (of the right size) so that I have a "get me home" kit, which I have for all the other parts of the fuel system, and save myself £60.  

 

The brazer (brazier?) also thinks the banjo may have failed due to a rather heavy joint being attached to the free end of the pipe, secured to a super-thick reinforced pipe. I think this change was made 15 or so years ago to comply with BSS ....  So he has tasked me to find some way to support it and reduce vibration.

Edited July 14, 2019 by Scholar Gypsy

[Slim]

57 minutes ago, Scholar Gypsy said:

Thanks very much for the comments. I think I will go with this approach, buy a couple of banjo unions (of the right size) so that I have a "get me home" kit, which I have for all the other parts of the fuel system, and save myself £60.  

 

The brazer (brazier?) also thinks the banjo may have failed due to a rather heavy joint being attached to the free end of the pipe, secured to a super-thick reinforced pipe. I think this change was made 15 or so years ago to comply with BSS ....  So he has tasked me to find some way to support it and reduce vibration.

Without seeing it it's difficult to suggest a solution but I have my rigid fuel lines secured with rubber lined P clips. If space permits a 360 degree coil in the line may also help. 

[Guest]

8 minutes ago, Slim said:

Without seeing it it's difficult to suggest a solution but I have my rigid fuel lines secured with rubber lined P clips. If space permits a 360 degree coil in the line may also help. 

My previous boat was thus. It had a one cylinder engine that could shake the lenses out of your specs.

[Scholar Gypsy]

the photo shows (white arrow) the fail point, the short pipe from the aft injector to the 90 degree bend. It's failed where it meets the aft banjo union.  The orange arrow marks the flexible return going down to the fuel tank, too much weight on the short pipe I think.