tube flat

Elcaro · 29 April 2019, 19:13

Hi chaps, my Honda Honwave T30-AE suddenly got a flat tube.
It's never done that before. While I've had it it was fine, inflated, for about 18 months, then I deflated it to move it in my car boot and re-inflated it again about 9 months ago, and still fine. As it was a week ago.
I have just bought a new o/b - so is this sod's law ?! (haven't fitted the new o/b yet, there's no o/b on it at the moment.)
I also put it on a trailer, but it didn't get any damage doing that cos I got a lot of assistance. Before lifting it on I topped up the air. The assistance came from a group of young people of a female persuasion, so maybe that distracted me, but when I went back this evening and found the flat tube, I also found that I had left off the - what are they? dust covers? - the things you undo to get access to the actual valves. Could this have something to do with it?
I re-inlflated the tube. Obvs the next thing is to go back tomorrow and see if it's gone down again....

Any thoughts pls? Condolences? Do I need to throw myself in the water now?

TIA, Terry.

office888 · 29 April 2019, 19:23

Valve caps are mandatory for an airtight seal.

Elcaro · 29 April 2019, 19:58

Richard, thanks, that is good news and thanks for your prompt reply. I just need to keep my mind on what I'm doing in future! Makes a lot of sense because the only difference related to air pressure between the previous periods of retained inflation and the last week is exactly that: the caps were left off this last week.
Regards from Terry.

willk · 29 April 2019, 23:23

Quote:

Originally Posted by Elcaro

Richard, thanks, that is good news and thanks for your prompt reply. I just need to keep my mind on what I'm doing in future! Makes a lot of sense because the only difference related to air pressure between the previous periods of retained inflation and the last week is exactly that: the caps were left off this last week.
Regards from Terry.

Yes - the dust caps are part of the "system" as they have an o-ring seal on them. You probably need to clean the inner valve that is held shut by pressure and check that the ring on the dust cap is good as well.

Poly · 30 April 2019, 07:46

Quote:

Originally Posted by willk

Yes - the dust caps are part of the "system" as they have an o-ring seal on them. You probably need to clean the inner valve that is held shut by pressure and check that the ring on the dust cap is good as well.

Is the o ring to keep the air in or water (etc) out?

jeffstevens763@g · 30 April 2019, 08:07

Quote:

Originally Posted by Poly

Is the o ring to keep the air in or water (etc) out?

both but primary its the second seal

Elcaro · 30 April 2019, 15:41

Hi all.

Richard office888, willk, Poly, jeff, thanks for your comments.

I went back earlier this afternoon and the boat is still inflated.

I have learned something about those caps. Although I would normally have replaced them.

I shall keep an eye on things and check valves and caps.

Regards from Terry.

jeffstevens763@g · 30 April 2019, 19:18

Don't forget the temp change Terry if they go a little soft with it getting colder

willk · 30 April 2019, 21:18

Quote:

Originally Posted by Poly

Is the o ring to keep the air in or water (etc) out?

Bit of both, IMO. There is a seal on the cap that is airtight, clearly the cap keeps random crap out of the valve. The inner valve can pass air due to a poor seating (grit or whatever) but the outer seal will hold. I've had sections deflate when the cap was missed - always on the hard obviously. Same experience as the OP.

Elcaro · 01 May 2019, 12:01

willk, yes I guess the fact that 2 out of 3 hull sections and the keel stayed up or at least didn't seem visibly deflated maybe means that the valve on the section that went down is a bit suspect - or maybe got some grit in it or something.
jeff, yes the temperature! It's been a funny year so far - a few weeks ago I was worried about the effect of the heat lol.

Guys, at the risk of highjacking my own thread I don't seem to be able to get up to the specified pressures (.25 for the tubes and .35 for the keel) or even close, using a foot pump that came with the boat. Could my manometer be duff or is that unlikely?

- Terry.

jeffstevens763@g · 01 May 2019, 12:10

Quote:

Originally Posted by Elcaro

willk, yes I guess the fact that 2 out of 3 hull sections and the keel stayed up or at least didn't seem visibly deflated maybe means that the valve on the section that went down is a bit suspect - or maybe got some grit in it or something.
jeff, yes the temperature! It's been a funny year so far - a few weeks ago I was worried about the effect of the heat lol.

Guys, at the risk of highjacking my own thread I don't seem to be able to get up to the specified pressures (.25 for the tubes and .35 for the keel) or even close, using a foot pump that came with the boat. Could my manometer be duff or is that unlikely?

- Terry.

it might be, get one of these mate job done set it to pressure and it cuts off

https://www.decathlon.co.uk/0-15-psi...d_8387582.html

Elcaro · 01 May 2019, 13:38

jeff, yes thanks I'll have a look at electric pumps. It might not always be easy / possible to get the car near enough to the boat. I suppose you could always wheel the boat up the bank to the car's closest point of approach. Or stop the car on the track above where the boat is and extend the wire ... but you'd have to cease operations and move along if another vehicle came along. All a bit awkward really.

When I bought the boat the bloke selling it had an electric pump, which he used to pump the boat down to deflate it so I could put it in my car. The footpump came with the boat but he was keeping the electric pump cos he was getting another SIB. As far as I can recall that pump had it's own battery, or maybe a separate battery pack - no cars were involved. I'll have another look online, couldn't see one like it last time I looked.
Regards, Terry.

jeffstevens763@g · 01 May 2019, 13:57

i got a 20 amp hour gel battery off ebay £20 only small it runs my chartplotter too

Fenlander · 01 May 2019, 13:57

Just get a 7ah-20ah battery from Ebay to run the pump. To remove the need for a lead to the car is life changing.

Ha ha… snap Jeff!

jeffstevens763@g · 01 May 2019, 14:14

Quote:

Originally Posted by Fenlander

Just get a 7ah-20ah battery from Ebay to run the pump. To remove the need for a lead to the car is life changing.

Ha ha… snap Jeff!

ha ha you usually beat me david

you dont have to be as elaborate as mine the battery is behind the voltmeter with an accessory socket to plug the pump into the engine charges it so always have a full battery.

Elcaro · 01 May 2019, 15:24

Fenlander, Jeff, yeah I found that battery pump that guy had - £200 !! So yes a pump and a battery is much cheaper.
I confess I don’t know what a gel battery is?
- terry

jeffstevens763@g · 01 May 2019, 17:38

Quote:

Originally Posted by Elcaro

Fenlander, Jeff, yeah I found that battery pump that guy had - £200 !! So yes a pump and a battery is much cheaper.
I confess I don’t know what a gel battery is?
- terry

All it means a Terry is normal lead acid is liquid and will spill if battery not upright with the gel any position is ok but I still set mine upright through habit but the way to go in a boat bouncing about that's all if you want to go technical the gel is more suited to the boat application

Elcaro · 02 May 2019, 09:34

Ah I see, thanks jeff.
Terry.

Elcaro · 02 May 2019, 18:40

Ah jeff, yeah I just went to check the boat again (it's in close proximity to the pub so it's no bother) and there's no sign of any deflation. So looks like we got the cause and cure sorted out.

Back on the pressure thing - 1st I'd like to try another pressure gauge. They're only a few quid. But - are they all the same screw fitting do you know? Mine's about 5/16 ths inch across the diameter of the threads. It screws into an adaptor for the Honwave valves.

TIA, Terry

jeffstevens763@g · 02 May 2019, 19:44

Yea standard thread BSP to be honest you get what you pay for there only a guide IMO being a cheapo
I use the itwit but if I use my bravo foot pump I just blow up until the tube rings when I slap it and leave it until the temp rises to the high twenties before I let air out whilst on the water I don't bother as the sea cools to tube a bit anyway. You can always leave the dust caps off in hot weather for a steady bleed to keep pressure down. I think 2.5psi is when you can press with your thum the tube in 1/2 an inch as a rough guide