Engine cutting out in deep water.

[andrew19]

A couple of weeks ago my Mk3's engine died in a section of deepish water, 40 to 50cm deep, As it started dying I pulled in the clutch and tried to rev the engine with no load but to no avail. I tried kick starting it in the water, about 10 attempts, with no luck and then decided to push it out on to dry land. A further 7 or 8 attempts and it started and ran as normal. Any ideas why it died in the first place. Someone in the group I was riding with suggested that I should route all the overflow tubes from the carb up to the top of the air box, currently they run down to dog bone area.
I'm wondering whether to go on a rideout to Strata Florida tomorrow but don't want to get stranded in all the water section

[knackeredMk1]

Recommendations are correct. Route the tubes to the top of the airbox. Also the gearbox breather. Check the one way valve at the bottom of the airbox is working and the electrics are insulated.

[fallenmikethebike]

I.M.O., and all mods on my MK3, leave the overflow pipes where they are, as moving them higher can give rise to carburettor flooding issues.
Certainly link them out under the carb, then leave the one as previously routed, but cut the end of the pipe to and angle, and zip tie a bit of sponge around the end.
Re-route the breather to either the air box, or the headstock, laying in water of course neither of those points are much higher than the original routing, so staying perpendicular is helpful. I have added an in line fuel filter to the end of this pipe to help keep the crud out.
The top of the air box might benefit from some additional ventilation, but that's your choice.
Make sure your filter is well oiled for tomorrow, and take a couple of spare plugs.
Some silicone spray will help disperse the water.
Generally as long as you can see the top of the front wheel the bike should be happy to run in that depth of water, with occasional dips into deeper water, just not as deep as I went on my old AR, when I literally ended up having to swim out .
Mike

[andrew19]

Thanks for responses, Decided to route all tubes to top of air box and sealed airbox cover with silicon grease only to find trip to Strata is off - I guess water levels must be too high after all this rain plus more tomorrow.

Mike , which one is the breather tube? There are 3 clear polythene tubes on my carb and I'm not sure what each one does - I guess I could look at the carb diagram in the Leisure Trail manual but it is in the shed at the bottom of the garden and there is no electricity in the shed.

I'll let you know how it performs tomorrow - I expect there will be some water sections in and around Brechfa which is where we are now going. Thanks again

[fallenmikethebike]

The breather pipes are to either side of the slide body, link them out above the carb then take upwards. The overflow, from the bottom of the float bowl, leave pointing downwards, [ that's in IMO], for the reason as previously stated.The breather from the gearbox is also best placed where Steve said as well, just make sure you don't overfill the gearbox, as this can lead to quite a mess in the airbox otherwise Also make sure the airbox drain valve is clear of oil bound dust, which makes for quite a sticky goo.
Mike

[pudzie83]

i have my breather pipes routed up my frame and tucked in behind my engine/earth brackets another tip i have is sticky back rubber strips around the inside of subframe on the airbox my filters kept nice and dry

[andrew19]

Thanks for all the tips

Unfortunately my rideout was cancelled so I did not get to test my arrangement. Mike, I'll be redirecting my overflow tube back to to its original location near dog bone.

Pudzie I don't follow the stick rubber strips tip. If possible a photo would be appreciated.

[fallenmikethebike]

I believe he's referring to the top of the airbox, at the back, where water fro the back wheel can get thrown forwards and into the top of the air box, I think
Mike

[pudzie83]

thats the one mike ive sealed off under the seat as much as possible with a 99p bodge .I was going through puddles nearly the same size as myself the other week and not a drop of water made it in....a proud 99p moment lol