Help : Advice on Fuel Hose Conection (Yanmar 3HMF 27-HP)

CapPugwash

CapPugwash

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Hello all.

I'm in a spot of bother and am looking for some advice. I am on anchor and have sprung a fuel leak.

My engine fuel filter was replaced by an engineer at the begin of the season and soon after I discovered a significant fuel leak. The hose between the lift pump and the new fuel filter was leaking. It transpired the nut had not been tightened properly. They advised to tighten both ends up, which I did and the leak was reduced to a trickle. I have been mopping up minor amounts ever since. Today it was worse so I tightened it up some more, but it started to spin. I took it out and there seems to be some sort of metal seal on the screw. I am guessing that when I tightened this end, I broke this seal causing the drip which i made worse today resulting in fuel spraying.

Is anyone familiar with what this seal would be, solder? I have a soldering iron but I'm not sure I'll be able to replicate such a seal. How about glue?

FuelHoseScrew.jpeg
 
Should be a dry connection with copper or alloy washers on both sides
its worth keeping a supply of washers to replace rather than reuse old ones as they can squash or deform
 
CapPugwash said:
Hello all.

I'm in a spot of bother and am looking for some advice. I am on anchor and have sprung a fuel leak.

My engine fuel filter was replaced by an engineer at the begin of the season and soon after I discovered a significant fuel leak. The hose between the lift pump and the new fuel filter was leaking. It transpired the nut had not been tightened properly. They advised to tighten both ends up, which I did and the leak was reduced to a trickle. I have been mopping up minor amounts ever since. Today it was worse so I tightened it up some more, but it started to spin. I took it out and there seems to be some sort of metal seal on the screw. I am guessing that when I tightened this end, I broke this seal causing the drip which i made worse today resulting in fuel spraying.

Is anyone familiar with what this seal would be, solder? I have a soldering iron but I'm not sure I'll be able to replicate such a seal. How about glue?

View attachment 120631
Click to expand...

That looks like a standard Banjo connection. From your description I think you've stripped the threads in the filter housing. Can I see bits of aluminium in the threads of the Banjo Bolt?

ETA cross posted with pvb

Another thing: there should have been washers on both sides of the Banjo, copper or possibly fibre. Only one washer showing in your photo.
 
Thanks all.

You're right, just spent some time on it have determined that the thread inside the fuel lift pump is shredded. New lift pump required, I'll replace the hose too. Not sure I can do the fuel lift pump myself but at least I know what needs to be done.

Luckily there's a ferry terminal in the bay.

Thanks again.
 
That pic is your lift pump and it sounds like you have stripped the thread. You may be able to get it helicoiled at a local garage or engineering workshop, otherwise i'm afraid you will need a new pump. Copper washers need to be annealed before use and reuse. Just heat them up to red hot on the cooker and drop them into cold water. This softens them so that they seal. Or replace them with dowtywashers which can just be reused time and time again. As Penarth 3 says there should be two washers per banjo.
 
Laysula said:
That pic is your lift pump and it sounds like you have stripped the thread. You may be able to get it helicoiled at a local garage or engineering workshop, otherwise i'm afraid you will need a new pump. Copper washers need to be annealed before use and reuse. Just heat them up to red hot on the cooker and drop them into cold water. This softens them so that they seal. Or replace them with dowtywashers which can just be reused time and time again. As Penarth 3 says there should be two washers per banjo.
Click to expand...

FFS, isn't it easier to use new washers? And I doubt helicoiling is much cheaper than a new pump.
 
Laysula said:
That pic is your lift pump and it sounds like you have stripped the thread. You may be able to get it helicoiled at a local garage or engineering workshop, otherwise i'm afraid you will need a new pump. Copper washers need to be annealed before use and reuse. Just heat them up to red hot on the cooker and drop them into cold water. This softens them so that they seal. Or replace them with dowtywashers which can just be reused time and time again. As Penarth 3 says there should be two washers per banjo.
Click to expand...

Thanks!

There were two washers, the other is on the floor.
 
penberth3 said:
FFS, isn't it easier to use new washers? And I doubt helicoiling is much cheaper than a new pump.
Click to expand...
Yup. But if you haven't got new ones you need to do something and overtightening is not the way to go as the OP has found to his cost. If your away from home then helicoiling, if you can get it done locally is better than waiting three days for a new pump to be delivered, even if it does cost the same as a new pump.
 
Any updates? Looking at mine yesterday, if your still struggling, as a get you home fix you could possibly anneal the washers and use a small G clamp across both banjo bolts to hold the stripped bolt in place.
 
Laysula said:
Any updates? Looking at mine yesterday, if your still struggling, as a get you home fix you could possibly anneal the washers and use a small G clamp across both banjo bolts to hold the stripped bolt in place.
Click to expand...

Inventive thinking points earned, I reckon that would work! Temporarily.

Stowing that one away in the brain locker

Lift pumps three bolts, two hoses and a gasket not difficult, it's at the beginner end of the spectrum.
 
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