Fuel Hose

[roody262]

What fuel hose are people using in their ribs?

I recently replaced the hose on mine with Nautilus fuel master but it seems to be staining/dyeing the petrol in the lines a red brown colour over a period of time (8 - 12 hours)

Many thanks

[Pikey Dave]

Originally Posted by roody262

What fuel hose are people using in their ribs?



I recently replaced the hose on mine with Nautilus fuel master but it seems to be staining/dyeing the petrol in the lines a red brown colour over a period of time (8 - 12 hours)



Many thanks

I use Parker hoses & filters etc, top quality, doesn’t say “Marine” on the packet so there isn’t a boaty premium. Oh! And I have a depot nearby[emoji106]

[Nasher]

I'm actually going to be purchasing fuel hose this week too, but am still deciding which exact size to buy as every connection point on my RIB is a different size.
Fuel pump at engine.
Flow sensor for Navman Fuel Computer
External Filter - although those can be changed
Primer bulb - again could be changed
Standpipe from underdeck tank
All different.

However.
I believe the latest relatively easy to obtain Ethanol Proof spec is SAE J30 R9.
Perhaps somebody with better knowledge can comment before I order it!
Beware, many hoses advertised as Ethanol proof are not up to this spec.

Edit
It appears I may have read my notes slightly wrong.
SAE J30 R9 is E10 Ethanol proof AND rated to @100psi for Fuel Injection systems
SAE J30 R7 is E10 Ethanol proof but not high pressure rated.
Because the fuel line to an outboard is not under pressure the R7 should suffice.
Be really happy for somebody to argue this, info available is sketchy and variable even between well know manufacturers websites.

[Pikey Dave]

Originally Posted by Nasher

I'm actually going to be purchasing fuel hose this week too, but am still deciding which exact size to buy as every connection point on my RIB is a different size.
Fuel pump at engine.
Flow sensor for Navman Fuel Computer
External Filter - although those can be changed
Primer bulb - again could be changed
Standpipe from underdeck tank
All different.

However.
I believe the latest relatively easy to obtain Ethanol Proof spec is SAE J30 R9.
Perhaps somebody with better knowledge can comment before I order it!
Beware, many hoses advertised as Ethanol proof are not up to this spec.

Edit
It appears I may have read my notes slightly wrong.
SAE J30 R9 is E10 Ethanol proof AND rated to @100psi for Fuel Injection systems
SAE J30 R7 is E10 Ethanol proof but not high pressure rated.
Because the fuel line to an outboard is not under pressure the R7 should suffice.

I’d try & upsize the various fittings to the largest size in the run. Even if it means changing the filter & primer bulb. New bulb & filter is a good call in any case.

[Nasher]

Thanks PD
Sorry Roody 262, feel like I've hijacked this, although it probably helps you too.

Yep, would be good to upsize them all, but is difficult because the fitting at the Engine fuel pump isn't the largest.

The External filter is a complete brand new assembly but as I can easily change the hose connections I could have an easy hose size change either side of it.
Interestingly the bore of the fitting at the Engine fuel pump is significantly smaller than the min hose bore Mercury recommend.
Unfortunately I don't have the Fuel hose tail the engine would have been fitted with from the factory as it was removed when the engine was de-rigged by it's last owner.

The hose spec itself is the thing I'm most interested in.

[User name]

Originally Posted by Nasher

Because the fuel line to an outboard is not under pressure the R7 should suffice.

It may or may not be relevant to your case, but vacuum should be considered too, especially if going with an oversized softer hose. It can collapse in on itself when drawing from the tank.

[Pikey Dave]

Originally Posted by Nasher

Interestingly the bore of the fitting at the Engine fuel pump is significantly smaller than the min hose bore Mercury recommend.

That’s normal. It’s the pressure drop along the length of the hose run that’s the issue. If the whole hose run was the same bore as the fuel pump fitting, the engine fuel pump would struggle to draw enough fuel from the tank, especially at full chat. You then get into fuel starvation which can cause all sorts of problems especially with EFI engines. If the fuel hose is a larger bore than the fuel pump fitting, then the resistance of the hose is negligible. It’s exactly like electrical wiring, the longer the run, the bigger the CSA of the cable needs to be to overcome voltage drop. The higher the current drawn, the worse the problem gets.
Substitute hose for cable, voltage for pressure/vacuum & current for fuel flow in the above analogy & it’s the same scenario.

[jeffstevens763@g]

just bought mine off force 4 chandlers decent price

[Nasher]

Thanks PD

Originally Posted by jeffstevens763@g

just bought mine off force 4 chandlers decent price

Thanks Jeff, what spec?
I've noticed a lot of chandlers and car places still pushing out R6 which isn't really up to E10.

[paintman]

^^^^That.
Lots of utter crap on ebay.

Can't see ethanol levels being reduced & finding E5 out in the sticks is getting more difficult so best to go with a higher rating.
Expensive but Codan is good.

[jeffstevens763@g]

Originally Posted by Nasher

Thanks PD



Thanks Jeff, what spec?
I've noticed a lot of chandlers and car places still pushing out R6 which isn't really up to E10.

here you go there are others you might want
https://www.force4.co.uk/item/Force-...8mm-Black/5R7A

[Nasher]

Thanks Jeff

It doesn't mention E10 or if it's R6,7 or 9.

Considering that there is so much R6 about, which can be sold as Ethanol/unleaded/modern fuel resistant because it's OK with E5, I'm going to make sure whatever I buy is going to be the very latest spec.

My boat isn't used a lot, and E10 fuel sitting stationary in a hose is worst case scenario for degrading it.

[jeffstevens763@g]

https://www.advancedfluidsolutions.c...-hose-95-c.asp

Found this Nasher hope it helps I went for mine just because I drain my system now since I had a water problem ��

[mick]

https://www.advancedfluidsolutions.c...hose-611-p.asp
Pretty sure I went for this when I did mine the other year

[mick]

Originally Posted by Pikey Dave

I use Parker hoses & filters etc, top quality, doesn’t say “Marine” on the packet so there isn’t a boaty premium. Oh! And I have a depot nearby[emoji106]

Where’s the depo your way

[Nasher]

Originally Posted by jeffstevens763@g

https://www.advancedfluidsolutions.c...-hose-95-c.asp

Found this Nasher hope it helps I went for mine just because I drain my system now since I had a water problem ��

Thanks Jeff, I'm honestly not picking on your threads, but your link to what you'd think would be a reliable company just shows the amount of confusion and misinformation there is around the subject making it hard to make a reliable decision.

In the link AFS claim R7, R9 and R10(submersible) hoses are all suitable for fuel injection.

I've now found this direct link to the SAE standards:
https://www.sae.org/standards/content/j30_199806/

It clearly defines that R7 is for low pressure systems:
See screen shot below.

[Nasher]

Originally Posted by mick

https://www.advancedfluidsolutions.c...hose-611-p.asp
Pretty sure I went for this when I did mine the other year

Mick
Thanks.
The R6 spec is where there appears to be the most conflicting information.

Lots of retailers selling R6 as suitable for E10 fuel.
But some manufacturers and motoring press rate it as only suitable up to E5 fuel.

It looks like the only safe decision to make is R7 or R9, and buy from a reputable source.

[jeffstevens763@g]

Originally Posted by Nasher

Thanks Jeff, I'm honestly not picking on your threads, but your link to what you'd think would be a reliable company just shows the amount of confusion and misinformation there is around the subject making it hard to make a reliable decision.

In the link AFS claim R7, R9 and R10(submersible) hoses are all suitable for fuel injection.

I've now found this direct link to the SAE standards:
https://www.sae.org/standards/content/j30_199806/

It clearly defines that R7 is for low pressure systems:
See screen shot below.

No probs you want it right for me in your situation and opinion I would blow the lines clear before storage that could be as simple as I bycicle pump from the engine end as I said earlier I now don’t trust fuel so drain off except for the engine pipe work