Jammed Water Filler Cap

[Little Dorrit]

Advice please on freeing a ceased/jammed water filler cap.

I replaced the water filler cap recently with a new one next to the original deck fitting the two metals were the same but I suspect because the deck fitting is very old there is sufficient difference between the metals to cause a reaction. The end result is a cap very firmly ceased onto the deck fitting!

Before I resort to a lengthy process of removing the fitting completely (it's virtually impossible to get access) I wanted to know if there are any suggestions on how I might free the cap enough to get it to turn.

I'm thinking of heating the outer deck fitting and cooling the inner cap...but how?? or should I simply resort to the horrible task of replacing the whole fitting (which I will eventually probably do do anyway.

 

[bikedaft]

Hammer chisel cap anticlockwise can be surprisingly effective

You don't have much to lose...

 

[Little Dorrit]

Tried that!!

 

[blackdogsailing]

Had exactly the same problem on my boat. i tried all manner of things. resorted to Bikedafts solution. It did require a very large hammer but it did come off. I had to replace it and put in a plastic one this time.
Chris

 

[elton]

Have you tried an oil filter wrench, such as http://www.halfords.com/motoring/garage-equipment/car-tools/halfords-chain-oil-filter-wrench-100mm

 

[bikedaft]

How is it designed to be opened? Flat surface with two holes? Get two bolts the right size and crowbar/prybar between them.

 

[Little Dorrit]

With an aluminium winch handle. Its a flush deck fitting and difficult to open without anything else. hammer and chisel which I tried started to damage the cap which may have eventually stripped it making it round.

 

[yerffoeg]

Seized metal fittings will usually release if you can can get heat on them. Light up that blowtorch!

 

[Little Dorrit]

Yep probably my first option!

 

[NOHOH]

Have you thought of flooding the cap with Freezer Spray...thereby cooling and reducing the diameter of the cap....and loosening it.... inside its housing........Probably a lot safer than using a blowtorch too

 

[bikedaft]

Can you extend the winch with a scaff pole etc?

 

[Phoenix of Hamble]

buy a cheapo (ie disposable) metal winch handle from a boat jumble, and introduce it to a hammer.

 

[West Coast]

We had the same problem on a Wauquiez Gladiateur, we drilled offset holes in the cap and inserted some pins - then used lots of leverage. We removed the pipe from below first, so no swarf went into the water tank

 

[onesea]

I had/ have the same problem... Never really solved it spray with WD40 regularly tried most of above... Now I just fill into the pipe below the deck....

 

[ballyabroad]

Had the same issue on my boat. Sprayed a can of Car Brake Cleaner (high evaporation/cooling effect) on the inner and came lose like a dream. Had already done the hammer and screw driver operation with little success.

 

[johnalison]

Had the same problem with the pump out cap which I solved by soaking with Plus Gas and leaving for a couple of days. Much better than WD40.

 

[Little Dorrit]

Solved. Very carefully heat the inner cap with a blowtorch. Then when the heat has transferred throughout the whole fitting spray some plumbing mates dry ice (£11 from tool station) at the cap...it released quickly and without any damage!