When to change diesel fuel hoses?

[davethedog]

Hello all,

Just wondering is there a time frame when you should look at replacing the rubber fuel lines on a diesel engine (tank to filter, filter to engine, return etc ).

 

[jamie N]

I'd have thought that a 'close visual inspection' would suffice to make the judgement, but I'm not a specialist.

 

[Alicatt]

Don't know how old the hoses are on my boat but they will/should be getting changed this week, the new hose should have been delivered yesterday.
The old pipes are hard and inflexible now plus there has been no filter / water separator between the tank and the engine, that will be getting fitted too, along with stop valves so I can shut the tank off. The Racor filter has been delivered but the rest of the order is still to arrive.
This is the next step before I replace the floor in the lazarette, don't want to splash the new planks with raw diseasel

 

[Dominicpriestley]

I recently changed my diesel fuel hoses as I changed to Racor filters, mounting them in a different location on the boat so changed the hoses at the same time. I assume the hoses were original as the previous owner of 20 years did not mention replacement or supply an invoice with replacement of fuel hoses on. They looked in perfect order when I removed them.

 

[davethedog]

Ok thanks as the hoses are approx 20 years old and look in good order.

 

[colind3782]

The diesel hoses on my boat have expiry dates printed on them, which I didn’t actually notice until the surveyor pointed out that they were years out of date!

 

[LittleSister]

What is the best hose to use for such purposes? Simple rubber fuel hose or something armoured?

 

[alan_d]

What is the best hose to use for such purposes? Simple rubber fuel hose or something armoured?

Something that doesn't have an expiry date printed on it?

 

[colind3782]

What is the best hose to use for such purposes? Simple rubber fuel hose or something armoured?

ISO 7840

 

[Refueler]

My 25 is 1973 build ... has metal fuel lines from under stbd fore bunk back to engine bay ... with 'rubber' to accommodate the twists / turns.
In about 2003 - engine was changed and when checking lines - all were found good and re-used. Its now 2024 and still in good condition.

 

[Plum]

What is the best hose to use for such purposes? Simple rubber fuel hose or something armoured?

The armoured hose will give more protection from abrasion otherwise the armour prevents inspection of the "rubber" hose. I do not use armoured hose.

 

[Refueler]

What is the best hose to use for such purposes? Simple rubber fuel hose or something armoured?

I defer to local auto shop and would buy heavy duty fuel hose designed for the job.

 

[Stemar]

Provided it's proper black fuel hose, I'd say, if it ain't broke...

If it's anything else, swap it for the right stuff, and, if you're disturbing it, and it doesn't want to go back together or seal properly, put new. I swapped my reinforced plastic fuel hoses, suspected of being about 25 years old, for the proper stuff last year, and it solved a couple of fuel issues that I'd been unable to fix.

 

[Jim@sea]

Hello all,

Just wondering is there a time frame when you should look at replacing the rubber fuel lines on a diesel engine (tank to filter, filter to engine, return etc ).

READ THIS
When this hose goes wrong it can cost a fortune.
You should consider checking the following hose, with an inboard diesel (petrol engines may be the same) its the hose which takes water and exhaust fumes from the engine to the exhaust outlet skin fitting. I bought a 15 year old boat and the first time I tried it I could not understand why the bilges were filling with water, It was the hose connection to the skin fitting where the jubilee clips tighten the hose to skin fitting,
It was the hose going soft with age, water had seeped into the hose and the metal coil within the hose had rusted so badly that it had snapped and a bit had flicked up out of the hose and water was pouring out.
The trouble was that the hose had been connected when they putt the engine in and before the superstructure was put on top.
I could not reach the hose, the diesel tank was in front of it and on top of the diesel tank was the GRP superstructure moulding.
Fortunately I am used to working with fibreglass.
I screwed a load of brackets to the superstructure moulding and cut a big section of the grp with a jig saw.
The brackets meant that after I had removed the diesel tank and fitted a new hose, the brackets would keep the section in place when I re-fibre glassed it, then after sanding down I hand painted some 2 pack Ford Diamond White (which appears to be a match for white GRP boat hulls) You would neve have known it had been done.
Goodness knows what It would have cost if a boatyard had done it.
15 year old hoses need inspecting.

 

[Refueler]

Adding to Jim@sea .... some hoses are twin wall and not unknown for inner wall to collapse and then start shredding / blocking