Dinghy pinprick air leak

[Sandy]

The dinghy has a pinprick air leak.

With my poor hearing I can't locate it hissing.

After an hour with soap and water peering at the surface I can't see any bubbles

Apart from better hearing aids and a visit to SpecSavers does anybody have any tricks to spot these tiny leaks?

 

[Farmer Piles]

Put a hose on it in such a way that it creates a film of water over the tube, you should see the bubbles come through the layer of water. Not foolproof but it often works on big inner tubes

 

[johnalison]

It is probably one of those jobs where you have to sink your pride and ask someone to assist, with four eyes being better than two.

 

[cpedw]

With glasses off, scan the surface at close range - a few mm. Your eye will feel the blast when it gets close enough.

 

[Fr J Hackett]

Strong soap solution wipe each chamber with a sponge, working your way gradually around. Hopefully you will see some bubbles try and keep it over pressurised.

 

[KevinV]

The dinghy has a pinprick air leak.

With my poor hearing I can't locate it hissing.

After an hour with soap and water peering at the surface I can't see any bubbles

Apart from better hearing aids and a visit to SpecSavers does anybody have any tricks to spot these tiny leaks?

I've had this with a tiny leak in the area between the floor and the tube, caused by sharp sand. With the dinghy on the dock the floor almost sealed the hole, making it impossible to find. I raised the dinghy on some fenders, then filled the bottom with water - to open the gap and show the bubbles.
On wheelbarrow tyres I've resorted to wiping with panel wipe - the breeze from the hole dries it faster than the surrounding area. Visible on black, not sure how well it would work on a dinghy.

 

[Refueler]

I know exactly what OP means .... it took me a while to find mine ..... basically by passing the hand slowly just a cm or so away from the surface ... I then felt the air on my palm ....
Squirty bottle with soapy water then confirmed it ....

Bottle of SealFlex poured in via the valves .... pump dinghy up and then roll it around a lot to distribute the sealant .... then before leaving dinghy to sit - pump more air in to make sure valves are clear of sealant ..

That pinhole I found - white sealant was squeezing out under pressure ... so I stood dinghy up so that pinhole was at bottom and sealant would be directly over it to set.

That dinghy stayed good for about 6 days before signs of any air loss .... it was still usable .. on 7th day creases started appearing in tubes ...
Means dinghy is still usable for short trips ...

I will now be using Gummipaint to liven up the outside and that should help add days to inflation cycle.

 

[thinwater]

Pointing out the obvious ... was it a high-bubble soap, such as hand dishwashing liquid? This should show the tiniest leak if done properly. A spray bottle works best, but a brush should work. Check every corner. Some can be sneaky, hiding under a reinforcement or rub rail.

Check the soap.

 

[nigel1]

This worked for me when soapy water solutions failed to find a pin prick leak in the dinghy floor.
Gas Leak detector spray,
Flomasta Gas Leak Detector Spray 250ml - Screwfix,
although available from other sources.
Spray on, leave, have a cup of coffee, finish coffee, return to dingy. Any leaks will be easily spotted, as rather than a bubble being produced, the spray forms a small molehill of foam over the leak.
I was looking for one leak, and ended up finding three pin prick leaks.

Was talking to the Cushendall RNLI coxswain a few weeks ago, and he told me they use the same spray on their inflatable boats.

 

[Refueler]

In local shop other day who caters for the fishing hobby ... they sell inflatables etc. I found a tube of liquid PVC ... amazing product. It starts to cure after application within minutes ... after an hour - you can run a finger over it and it appears dry.
Its designed for applying to pin holes to seal .. It works ! My other dinghy had a small cut ... paste sealed that. There were also 3 areas where outer layer had been caught .. tiny marks - applied paste and layer restored.

 

[Sandy]

Put a hose on it in such a way that it creates a film of water over the tube, you should see the bubbles come through the layer of water. Not foolproof but it often works on big inner tubes

Done that...

 

[Sandy]

It is probably one of those jobs where you have to sink your pride and ask someone to assist, with four eyes being better than two.

Done that.

 

[Sandy]

Pointing out the obvious ... was it a high-bubble soap, such as hand dishwashing liquid? This should show the tiniest leak if done properly. A spray bottle works best, but a brush should work. Check every corner. Some can be sneaky, hiding under a reinforcement or rub rail.

Check the soap.

Normal dishwashing soap from the boat.

I'll try a spray bottle.

Thanks.

 

[Sandy]

This worked for me when soapy water solutions failed to find a pin prick leak in the dinghy floor.
Gas Leak detector spray,
Flomasta Gas Leak Detector Spray 250ml - Screwfix,
although available from other sources.
Spray on, leave, have a cup of coffee, finish coffee, return to dingy. Any leaks will be easily spotted, as rather than a bubble being produced, the spray forms a small molehill of foam over the leak.
I was looking for one leak, and ended up finding three pin prick leaks.

Was talking to the Cushendall RNLI coxswain a few weeks ago, and he told me they use the same spray on their inflatable boats.

Thanks... if the spray bottle done not work then a visit to Screwfix for ma.

 

[Sandy]

In local shop other day who caters for the fishing hobby ... they sell inflatables etc. I found a tube of liquid PVC ... amazing product. It starts to cure after application within minutes ... after an hour - you can run a finger over it and it appears dry.
Its designed for applying to pin holes to seal .. It works ! My other dinghy had a small cut ... paste sealed that. There were also 3 areas where outer layer had been caught .. tiny marks - applied paste and layer restored.

I have the glue to fix the problem, finding the barsteward in the first place is the ...

 

[ylop]

Thanks... if the spray bottle done not work then a visit to Screwfix for ma.

Assume you've checked the valves too?

 

[Ray Purchase]

Talcum powder?

 

[B27]

Make sure you are pumping it up to the maximum pressure.
Some leaks only seem to leak when the seam is under stress.
I had a small leak which only seemed to happen when the dinghy was stored bow-up, and the leak was from the back.

 

[thinwater]

Assume you've checked the valves too?

Yes, this!

If it is a slow leak through the check valve, a few drops of glycerin in the valve and also around the cap seal can do the trick. It takes months to dry out, so it lasts, then repeat. A few drops will do no harm. Obviously, valves can be replaced. It's not difficult. Glycerine will help you diagnose this problem.

 

[Cardinal]

In local shop other day who caters for the fishing hobby ... they sell inflatables etc. I found a tube of liquid PVC ... amazing product. It starts to cure after application within minutes ... after an hour - you can run a finger over it and it appears dry.
Its designed for applying to pin holes to seal .. It works ! My other dinghy had a small cut ... paste sealed that. There were also 3 areas where outer layer had been caught .. tiny marks - applied paste and layer restored.

Was this effective on a hypalon dinghy?