Topic: Electrical water?

[dpen]

I'm having some troubles in wet weather so thought I'd check if there were any common gremlins with these bikes.

The K7 starts to miss & run on three then two cylinders in the wet & has done since I got it a few years ago. I've just been too slack to look into it but with the demise of my other bike it's gotta be fixed.

The strange thing is that it only misses when on the move.

I have sprayed it with a hose & have sprayed water with a spray bottle into all nooks & crannys (coils, wiring joins etc) with it standing still and - no miss. This is both at idle & revving.

Go for a ride & it's a different story.

A few hundred yards & it misses, depending on the severity of the rain, either one or two cylinders conk out.

Stop & rev it for about 30 seconds & it's ok.

Ride off again & it misses. (forgot to mention there are no troubles in the dry)

Plug leads etc were original so they were the first to go. New leads spliced on & caps from a Chevy - nice fat spark & no dramas if you drown the engine with a hose.

Feeling the exhaust headers, two & three seem to be a bit cooler than the outer ones - coil?

Points are very good ( after being dressed) & the points cover can be hosed with no missing.

Any opinions?

[merc2dogs]

did you spray the handlebar and ignition switches too?

 when riding in rain at any speed, the majority of the water is going to come straight on almost level with the ground, but a good deal of it is also going to be thrown up and forward by the tires, is anything in position that the tire can throw water to a sensitive area? 

 not sure what breather you have, but my old 75 would pull enough water into the breather off the back tire or around the engine to choke and stutter, always thought it was spark, but noticed water dripping from the screw in the bottom of the airbox after a rain, pulled it off and there was quite a bit of water in it. Drilled a couple drain holes in the bottom and didn't have problems afterwards.

ken.

[mrbreeze]

How good is your points cover sealed? That on top of air cleaner/breather. Bad plug wires/caps. Lots of bad things can happen when water is introduced to a bike that isn't ready for it.Keep experimenting and you will find the culprit!!

[TwoTired]

I cured symptoms as you describe by making a neoprene points cover gasket.  This keeps the water out of the points cavity and is reuseable.

It there is water inside, the heat makes water vapor and it then condenses on the points.  Very erratic, progressivly worse ignition.  Gotta keep it reved to stay running. 

I can ride in a downpour now without the engine missing a beat with the new gasket.

Cheers,

[johnny-from-bel]

I had it to, it was the cork seal on the points cover

[dpen]

Good seal around the points cover, new (and good) leads & caps.

Worse thing about being in the trade is that you overlook the obvious on your own machine.

Breather sounds like a well-worth-check.