Bleeding a Nanni 50 hp

[petermills]

Looking for some help and advice. My previous boat had a Vetus engine which was self bleeding. Changing filters was no problem. My current boat has a Nanni 50 hp engine and is due for filter changes. Is there any hope of acheiving this without bleeding the system? If not, I will have a problem as the engine is enclosed within a fixed grp housing with hardly any space to get at the fuel pump. I am unable to get a view of the pump so I'm wondering if anyone has a picture of the pump which will allow me to see and then feel for the priming lever?? Does anyone have any tips on changing the filters (primary and secondary) which might overcome the need for bleeding on this size of Nanni diesel engine? Any advice would be very welcome...........

 

[black mercury]

When changing the engine filter you could fill it with diesel before screwing it on. The priming pump is below the main injection pump, from your description it would seem that you will need to find the lever by feel. If you can get a mirror down that side of the engine and see the lever it will make finding it by feel much easier. You will need to say what type of pre filter is fitted as to assert if it can be filled with diesel, or have to be bleed afterwards. It will be much easier if the engine is gravity or the fuel tank is above the level of the pre filter. If the fuel line from the pre filter to the engine is rubber what you can do is remove this pipe at the pre filter (after fitting new filter) and using a priming bulb (you can buy them in a motor factors) with a short length of rubber fuel line between it and the filter use the priming bulb to suck the diesel through. Once you get diesel through the pre filter reconnect the original fuel line. Then change the engine fuel filter by filling the new one with fresh diesel. If you need to the bleed screw is untop of the engine filter housing. Good luck.

 

[VicS]

Is this an N4.50 ?

If it is doesn't the section in the operator's manual on replacing the fuel filter help ?

Note that it says:- Do not fill the new filter with fuel before assembly.

https://nannienergy.com/downloads/manuals/N4.40-N4.50/Manuel N4.40-N4.50 ENG - 970316085.pdf if you have mislaid your copy

 

[petermills]

Many thanks for your help. The link to the Operators Manual was most useful. The version that I have is nowhere as detailed . This will be a job for the weekend. (It is the N450 engine). Thank you again.........