water tank inlet lock

[Bikerbill]

On our new 2014/14 Interstate motorhome I'm quite concerned about the screw off chrome metal cap for the manual water tank fill. I've heard rumors that some have accidentally had diesel added and I'm also concerned about pranksters opening it and dumping something into our water supply. Has anyone had any luck finding a locking screw-type cap to replace the current cap?

[73shark]

Welcome to the forum. Have you tried RV suppliers such as camping world?

[russ240]

I have the same concern but have never seen anything. Good luck in your search and let us know if you turn something up!

[Boxster1971]

I also would like to have a lock on this water fill. So I took a close look at my water gravity fill cap and determined the item is made by Perko with Fig. 540 on it as a part number. Then through the magic of Google I found the Perko web site and this is actually a Boating/Marine item used for both fuel and water vented fillers. The following links will take you to the details.
Perko Web site for Fig. 540
http://www.perko.com/catalog/category/fills_and_vents/product/57/ [Click on the Ordering tab to see part number for water filler]
Perko Web site for vented filler lock:
http://www.perko.com/catalog/category/fills_and_vents/product/207/

I’ve attached a copy of the instructions for the lock so you can see how it works.
They are available on Amazon and eBay, plus lots of other marine suppliers. This is not a normal RV item.
Enjoy,

[PSchw]

Thanks Mike just ordered it from Amazon.
Peter

[David M]

Me too. Thanks Boxter1971! I hope I ordered the right part. i only ordered the locking fill insert, p/n 0525DP0BLK.
David

[russ240]

Love this forum. Thanks Mike!

[Bikerbill]

OK, I got my answer and thanks. Will order it soon.

[Boxster1971]

Mine came for eBay supplier Northern Marine Discount today; p/n 0525DP0BLK. It goes into the filler fairly easy but I found it a bit tricky to remove.

[PSchw]

Got mine today too. Tried it out right away got in OK as I turned and try to pull it out the key with the lock came out but not the insert. Could get the insert out with a needle nose plier but I assume this should be not normal operating procedure.
I guess quality could improve a little now I waiting for a response from PERKO for replacement. Hope the next one works better.
You may want to makes sure you have a needle nose plier in your rig.
Peter

[Boxster1971]

I found it took both hands to remove the lock. I used one finger to hold the lock body from turning while I tuned the key to release the lock and pull it out of filler. I didn't need tools just a little finesse.

[PSchw]

Did not pull hard just tried turning the key and pulling the locking cylinder came out then you have no choice then using a needle nose plier. I assume it is a manufacturing defect so much for Made in the USA.
Hope my second one will be OK still I will keep a needle nose plier in the rig.
Peter

[Boxster1971]

Originally Posted by PSchw

Did not pull hard just tried turning the key and pulling the locking cylinder came out then you have no choice then using a needle nose plier. I assume it is a manufacturing defect so much for Made in the USA.
Hope my second one will be OK still I will keep a needle nose plier in the rig.
Peter

Ouch! That doesn't look good.

[David M]

Just got mine today, and the tumbler mechanism came out of mine too while trying to remove the insert. I too had to use needle nose pliers to get the insert out. I'm not sure if I'm going to keep this because I don't want to be in a situation where I can't fill my fresh water tank. Very disappointed
David

[73shark]

Most locks of that type have a retaining mechanism. I wonder if they left something out since this seems to be a problem with more than just one.

[David M]

Originally Posted by 73shark

Most locks of that type have a retaining mechanism. I wonder if they left something out since this seems to be a problem with more than just one.

This has a retaining mechanism, but the spring for the retainer is weak (I'm guessing for ease of assembly purposes). The instructions says to use the key to extract the insert, but the tumbler pulls out instead due to the weak spring. It would probably work ok on a straight inlet pipe, but our Interstates uses a curved water inlet pipe.

[PSchw]

Not good to hear I hoped mine was just a bad one looks like there are having a general problem. I send a email to the address on the website no response in 2 days. Maybe I should just return it to Amazon.
This forum is great with a lot of good people with all there experience helps a lot for a newbie like me.
Thanks
Peter

[PSchw]

I fixed mine. Added a pice of plastic opposite of the snap mechanism which now limit the wiggle you got to pull it out. I tried it several times worked fine. Still will carry my needle nose plier.
Looks like the hole in the plastic insert for the key cylinder is to big.

[Kwils25]

Originally Posted by PSchw

I fixed mine. Added a pice of plastic opposite of the snap mechanism which now limit the wiggle you got to pull it out. I tried it several times worked fine. Still will carry my needle nose plier.
Looks like the hole in the plastic insert for the key cylinder is to big.

The lock mechanism came out n mine as well. I was able to reinsert it and finally get the device out of the neck. At this point I am not confident of using it. I don't need something more to worry about when I'm on the road. The lock is getting sent back.

[Willtan]

I too was perturbed that the water inlet (both city water and tank fill) on my 2013 Interstate was unsecured. (While the dump hose and black tank flush is locked????). I opted to secure the water inlet using an access hatch:
https://a.co/d/4OowPAA

The access hatch is attached (with screws) to a 3-D printed mounting base that is secured to the van chassis using 3M VHB double sided tape (to avoid drilling holes into the van chassis). Silicone caulk was used all around the perimeter to seal the VHB tape. The access hatch matches perfectly with the existing dump hose hatch.

One unfortunate aspect of the Thetford hatch is that it only came with one key. It cost me $5 to have one duplicated at the hardware store.