Maniner 40 (RNLI) Fuel Leak

NorfolkPete · 30 April 2021, 14:24

I am trying to work out what this part is? Whenever i prime the fuel this block leak through a hole at the bottom....it this normal?

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sorry but the photo is wrong way up and i cant seem to get it right. Its the block with the white plastic pin operated by the throttle cam i am trying to understand.

Pikey Dave · 30 April 2021, 18:25

Quote:

Originally Posted by NorfolkPete

I am trying to work out what this part is? Whenever i prime the fuel this block leak through a hole at the bottom....it this normal?

Attachment 137164

sorry but the photo is wrong way up and i cant seem to get it right. Its the block with the white plastic pin operated by the throttle cam i am trying to understand.

I’m not at all familiar with that engine. But, if it’s genuine ex-RNLI, it may be a fuel cut off device to cut the fuel in the event of an inversion. Like I said, it’s a guess & I could well be talking a load of Botox.

samt · 01 May 2021, 06:24

It's a fuel primer, if it's leaking the diaphragm has gone brittle and split. You'll can get service kits for them, careful taking it apart, the are two springs and a tiny ball bearing inside.

NorfolkPete · 01 May 2021, 07:43

Thanks Samt, that does make some sense. I have been searching for the part name and number or even a diagram that has has this explained and can find nothing. Even now i have been doing more googling and cant find the relevant parts/drawings/ description/service kit....any ideas would be much appreciated. I think i have found the throttle cam parts (which i dont need) but not the associated primer but i may be describing it incorrectly?

paintman · 01 May 2021, 09:08

You'll need to enter more details about your engine to narrow it down but you might find what you're looking for in the exploded diagrams on here. Certainly been a help to me:
https://www.crowleymarine.com/

samt · 02 May 2021, 09:03

It looks the same as as the primer pump on the 15hp 2 stroke. Whats your serial number?

Quote:

Originally Posted by NorfolkPete

Thanks Samt, that does make some sense. I have been searching for the part name and number or even a diagram that has has this explained and can find nothing. Even now i have been doing more googling and cant find the relevant parts/drawings/ description/service kit....any ideas would be much appreciated. I think i have found the throttle cam parts (which i dont need) but not the associated primer but i may be describing it incorrectly?

NorfolkPete · 02 May 2021, 10:33

The serial number is OP231152 and it looks like a 2003 model. The sticker is a little worn. its an RNLI 40HP 2 stroke manual start. No drawings i can find seem to show this feature....or i am looking in the wrong place. Thanks for your help i will look up the 15hp models to see what i can find by way of similarity.

samt · 04 May 2021, 09:13

I can't see it either.

Pretty sure those parts will be in the 15hp repair kit. P/N 1395-97611

Quote:

Originally Posted by NorfolkPete

The serial number is OP231152 and it looks like a 2003 model. The sticker is a little worn. its an RNLI 40HP 2 stroke manual start. No drawings i can find seem to show this feature....or i am looking in the wrong place. Thanks for your help i will look up the 15hp models to see what i can find by way of similarity.

samt · 04 May 2021, 09:16

Ignore the gasket in the top right.

Fenlander · 04 May 2021, 10:15

If I remember the primer on my 15hp models it was part of the carb and the plunger operated by the choke knob a few times on a cold start to squirt fuel into the carb throat.

On Pete's image his device seems remote from the carb and it's not clear what operates it.

So... is it that grey cam that pushes the plunger down? Assuming so what operates the cam... throttle? Again assuming so what is the degree of plunger operation related to throttle opening.... such as gradually push down related to throttle opening... push down immed throttle is opened and stay down... or something else.

Also important where do the rubber tubes to the device come from and go to... source of fuel or perhaps crankcase?

samt · 04 May 2021, 11:39

Found it for you, it's an accelerator pump from a 100 to 125hp 4 cylinder 2 stroke.

Likely fitted as a special mod to the 40hp for the RNLI.

P/N for the pump is 14687A2

Repair kit that you need is 1395-811287

Most likely the same diaphragm in the 6hp to 25hp carb repair kits I mentioned, certainly looks the same.

Fenlander · 04 May 2021, 11:43

Good detective work!

For interest though would still like to know if it's a single shot of fuel like a carb mounted pump or stays open with the cam above idle... also where it gets its fuel from and where it's sent to.

NorfolkPete · 04 May 2021, 16:35

Amazing....thank you so much team. The cam is part of the throttle linkage and i think stays open, or at least the pin in fully depressed, when on full throttle. Fuel comes directly from the tank then on to the carb. There is some adjustment on it on how it is installed and i will have to work out b y trial and error. Its leaking had a disastrous effect on fuel consumption and now that is making sense too. Thanks again for all your assistance and detective work.