# Repairing a lockable water filler cap



## andrewball1000 (Oct 16, 2009)

My cap, like many others, had seized making it impossible to lock. This didn't bother me till I realised that the rubber washer was not seating and letting water out / air in.

Buying a replacement would mean that I had yet another key, so last night I had a go at dismantling the cap. The following are some pics of how to get in and what to do when you do.

Blunt table knives make excellent tyre levers. The first can be inserted with a slight twist, followed by 2 others. One can then be dragged round and the cover pops off to reveal the components.


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## teemyob (Nov 22, 2005)

*Info*

Thanks for the info and taking the time to put the photos up.

TM


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## Morphology (Jul 23, 2010)

So, once you've got it apart, then what?

Do you simply clean and lubricate all the parts and re-assemble?

Morph.


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## andrewball1000 (Oct 16, 2009)

What To Do When You get Inside.

The Central column, that holds the lock barrel, has a cam/lever that extends to locate in the actuating cone and stops the cap from spinning. This allows the cap to be put on or removed. When the key is locked the cam retracts and the cap spins so it cant be removed.

The jamming problems on mine were caused by distortions in the central column. I used a craft knife to remove some, then a flat needle file on both the barrel and the cogs on the actuating cone.

I used a soft pencil on the surfaces as both a marker to show where it was jamming. Graphite also acts as a dry lubricant. When testing the fit, it is best to retract the cam so you can turn the two surfaces together. Leave it extended when pushing the actuating cone against the spring to test high spots there.


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## andrewball1000 (Oct 16, 2009)

More pics. 
Assembly is reverse of previous.
I now have a working, lockable filler cap with the same key as all the others.


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## Morphology (Jul 23, 2010)

Ha! I knew I should have waited. Many thanks for the clear explanation.

I have exactly the same problem, so I'll have a play at some point.

Morph.


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## solly (May 1, 2005)

*repairing lockable filler cap*

Very usefull well presented post. thanks.
Now when can we all come to your place to ours fixed  :lol:


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## FoweyBoy (Dec 7, 2006)

If you had to, can you remove the old lock barrel and fit it to a new filler cap? My A/S Nuevo came with some spare lock barrels. I assume the converter buys a set of locks, all to the same key, and fits them in the various doors, fillers etc.


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## andrewball1000 (Oct 16, 2009)

FoweyBoy said:


> If you had to, can you remove the old lock barrel and fit it to a new filler cap? My A/S Nuevo came with some spare lock barrels. I assume the converter buys a set of locks, all to the same key, and fits them in the various doors, fillers etc.


I couldn't see any easy way to do this and wouldn't like to try. The lock barrel has got to go in from one end or the other. If from the outside I would expect a circlip or something, but then this would be easy for any thief to remove. I suspect it is inserted from the inside. If you look at the last two pics you will see an end cap which holds it all in. I have no idea how this is held or removed and replaced. Luckily I did not need to find out


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## FoweyBoy (Dec 7, 2006)

FoweyBoy said:


> If you had to, can you remove the old lock barrel and fit it to a new filler cap? My A/S Nuevo came with some spare lock barrels. I assume the converter buys a set of locks, all to the same key, and fits them in the various doors, fillers etc.


Update. I bought a replacement cap from Autosleepers and they explained how to fit the spare lock barrel.

See also : http://www.motorhomefacts.com/ftopict-131766-.html


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## brynric (Oct 17, 2009)

Some time ago I had this problem and asked around for a solution. Possibly the daftest idea was to boil the cap. It was also the cheapest so I tried it.
It worked.
I'm sure someone will come up with an explanation of why.


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## Techno100 (May 8, 2010)

Me too
In Winter the outer exposed skin of the cap contracts more than the inner skin until they bind together. Boiling water expands the parts enough that they come free again. Copious quantity of silicon spray helps to keep it free. In the warmer months it should not occur


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## DTPCHEMICALS (Jul 24, 2006)

Andrew I had this problem after a few months of buying our mh over seven years ago.
I could not unlock the cap.
I squirted silicone spray into the lock, around the steel edges not where the key goes.
Within a few minutes of jiggling the key it unlocked.
Surprisingly I have not had to do anything since.
Dave p


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## tude (Feb 9, 2008)

*Water cap*

There is a easier way put the cap in boiling water for 5 mins I've done it many times
Tude


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## zappy61 (May 1, 2005)

I lost mine when in France a couple of weeks ago, I put it somewhere safe after filling up and drove off without it. Had to make a temporary one till I got home. A new one from Autosleeper cost me £22 so I thought I better make sure I don't leave it behind again. A small length of cord from a roller blind and two stainless self tappers and it won't escape again, it keeps it clean too.

Graham


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## Techno100 (May 8, 2010)

My cap key is on my ignition key ring :wink: SO I CAN'T FORGET IT :lol:


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## Techno100 (May 8, 2010)

I just bought this which I use with a water stop connector on my hose. While filling the locking cap sits in the locker with my keys attached.


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