Whale Water Heater

[Tony_374371542]

We have a friend with a 1997 Swift Challenger which has a Whale hot water system. He has a problem with the drain plug on the outside of the heater.
When he fills the and uses the system, warm water drips from the plug onto the ground. He has tried replacing the O ring and sealing the plug with ptfe but it still leaks. I think it may be the internal thread that is cracked, allowing water to escape.
I seem to remember an article I read somewhere about a repair that involved fitting a bush to the original internal thread with sealant and then a new cap or plug to that.
Has anyone any information about the problem or any suggestions regarding a repair?

 

[Gafferbill]

......the water heater is more likely a Carver unit.

Contact Gary at........................ www.arcsystems.biz

......or he may see your post and reply on this forum.

 

[Tony_374371542]

Thanks for the information Gafferbill. I looked at the link and the Carver diagram is the same as the unit on our friends van. I couldn't find any more information other than it may be the internal thread but will keep on trying.
Tony

 

[Guest]

There are two types of drain bung for the Carver Cascade water heater, up to June 87 and there after.
Early ones are 1/2" BSP thread but the later ones are what you might call odd-ball thread?!, both types though are readily available on ebay

 

[Tony_374371542]

Thanks for the replies.
I know he has replaced the plug at some stage but it still leaks, that's the reason I thought it may be the internal thread that's cracked.
I did look on e-bay and found a plug that had two O rings. The ad claimed it would cure the leak. Hopefully without breaching any forum rules, has anyone any experience of these plugs?
Tony

 

[Guest]

Regards ebay and the plug with two o rings, that's to buy two seals, you don't get the bung! Still I'm 100% certain only one is required. Further, never have I come across a crack or any other damage to the drain bung threads or casting.
So if it's leaking then the bung is not screwing in fully, least to date this is the only reason I've come across, this maybe tight threads in the casting and or poor sealing the o rings seat, both caused by a build up of corrosion.
Tell a lie, I've known the bottom of the screwdriver slot in the bung to crack and leak, however that's generally down to tight threads making it very difficult to screw in.
A little course wire wool wrapped round a 3/8" drill bit will soon clean out the threads and polish the o ring seat, what you are aiming for is the bung to screw in with ease using just your fingers, only the last half turn requiring a screwdriver or indeed a two pence piece should do it and the o ring should now be no longer be visible.
I'll also add, I never understood Carvers choice of o ring size and I'd assume others selling them have copied it, however I sell a slightly different size and have had no issues whatsoever!

 

[Tony_374371542]

Many thanks for the advice. It sounds as though the plug may need a bit of TLC. I will have to pin him down and have a look at the problem myself.
Tony