Diesel filler cap

[sadler25]

Does anyone recognise this diesel filler cap ? I have tried to undo it today without success using a standard two prong 'key'. It moves maybe 5 degrees then appears stuck.

The central hole is threaded and I have found a bolt that fits. I have tightened this up as far as I dare to see if this releases the mechanism somehow, but without luck. I have asked around the club today and nobody has ever seen a cap like this. Unfortunately the previous owner of the boat is no longer with us.

I need to check the diesel level and top up the tank before launch on Wednesday, help !!

 

[pvb]

Does anyone recognise this diesel filler cap ? I have tried to undo it today without success using a standard two prong 'key'. It moves maybe 5 degrees then appears stuck.

Is it a bayonet-type fitting? After you've moved it 5 degrees have you tried lifting it?

 

[penberth3]

Is it a bayonet-type fitting? After you've moved it 5 degrees have you tried lifting it?

When it stops, I'd try pushing it down then continue turning anti-clockwise. Be gentle with it!

 

[greeny]

Are you sure it's the filler cap and not something else like a vent.

 

[sadler25]

Is it a bayonet-type fitting? After you've moved it 5 degrees have you tried lifting it?

We tried both pushing it down, and lifting it, and there wasn't any vertical movement.

 

[sadler25]

Are you sure it's the filler cap and not something else like a vent.

It's connected to the large hose into the diesel tank, so I'm pretty sure that it is the filler.

There is a hardwood dip stick which is the right length to get the bottom of the tank through this filler. Interestingly I could not find the vent pipe from the tank, just the large filler hose, the feed from the bottom (with tap) and the return to the top of the tank.

 

[Plum]

It's connected to the large hose into the diesel tank, so I'm pretty sure that it is the filler.

There is a hardwood dip stick which is the right length to get the bottom of the tank through this filler. Interestingly I could not find the vent pipe from the tank, just the large filler hose, the feed from the bottom (with tap) and the return to the top of the tank.

Maybe it is a Perko filler that has the vent integrated under the cap like this https://www.amazon.com/Perko-0541DPGCHR-Chrome-Straight-Vented/dp/B0000AZ3OJ

Www.solocoastalsailing.co.uk

 

[Dipper]

We tried both pushing it down, and lifting it, and there wasn't any vertical movement.

Have you tried pushing it down before you turn it?

 

[greeny]

https://www.perko.com/images/catalog/pdf/Fig 0525 Instructions.pdf

Perko was a good clue.
Look at this data sheet and at the bottom seems to be your filler.

 

[sadler25]

https://www.perko.com/images/catalog/pdf/Fig 0525 Instructions.pdf

Perko was a good clue.
Look at this data sheet and at the bottom seems to be your filler.

Thanks, this looks promising.

My filler appears to be cast bronze and I know that the PO spent time working in the USA so it could be an old Perko filler/vent.

I'm still not sure why it has a threaded central hole, or why I can't undo it using my universal deck plate key.