Forum

[dave p]

Riding home a week ago in the pouring rain my Bullet (2008, iron barrel,kickstart)died.I thought I had run out of petrol at first but that wasn't the case.I checked for sparks, no problem there.After about half an hour I gave up trying to start the thing and called the breakdown service to take me home.
At home, I checked the bike over and could find nothing wrong so I removed the carb' and put it in my ultrasonic cleaning bath, just in case there were any internal blockages.
I put it back together but the beast still would not start.The job was abandoned over Xmas as I was away from home.This morning I returned to the shed to address the problem and would you believe it? A few kicks and the old so and so started!!
Now, why is that I wonder.

[stinkwheel]

You got a pod filter fitted?



The reason I ask is I had an odd fault with mine during the rain whre it would suddently die as if turned off then splutter, pop and pick up again.



It turns out the rain water was running down my front then pooling in a fold of my oilskins. Periodically, this pool would run down the inside of my right leg all at once, directly into the pod filter. Internal combustion engines don't run very well on water in that kind of quantity.



That doesn't necessarily explain why it was recalcitrant to start afterwards. Of course the obvious one is damp in the HT system leading to a weak spark. Especially with standard coils, there isn't a fantastic connection between the coil and the HT lead. It is a bit prone to corrosion too so the water could have been the straw that broke the camels back.



Also possible it was well flooded following repeated starting attempts and has taken a while to sort itself out?

[Chris [Stockport]]

Mine did that so I replaced the lead to the plug and all was well. On another occasion the "Distributor" had some water in it, again from heavy rain so I bought one of the rubber covers, that push on, from Hitchcocks.

[dave p]

Thanks for the replies chaps.My air filter is the aftermarket "tea caddy" type which draws in air from the open bottom of the box.I wondered if the element had become sodden and water had been drawn in from that source thus killing the engine.I've just removed the element which is bone dry if rather dirty.The shed is cold so I don't think a wet felt element would have dried out in a few days.I've ordered a new element anyway as the existing one is overdue for replacement.I'll now check the HT lead connections although a spark was always present,(outside of the engine !!) The points housing was checked by the roadside at the time of the incident and was completely dry.
Cheers Dave.

[Chris [Stockport]]

Out of interest, I've been using the tea-caddy filters for ages and ridden in a lot of rain, but not got the element wet yet. Sounds like yours needs a new clean one anyway.

I've had spark-plugs spark outside the engine, but not work when they're put back in. As a reaction to this I've replaced them or the (wet)lead with brand new, and all was well.

I wonder if an older lead breaks down somewhat and when wet just lets a bit of electricity through? That's the technical explanation. I have no idea, but that's what it felt like...

[stinkwheel]

Old HT lead can break down and arc all over the place. So the electricity is going otherwise than to the sparkplug. Electricity takes the path of least resistance so if that's jumping through a crack in the insulation to the engine instead of through the plug, that's what it'll do. It's more likely to do it when wet. Bullets have a particularly long HT lead that takes a lot of thermal abuse and go near a lot of metal parts.



Start it running in total darkness and look for sparks jumping to the frame and engine round the coil, HT lead and plug cap.

[Tim NZ]

Take a very close look inside the top of the coil output tower, and the end of the HT lead for water/oxidation corrosion...


If water is allowed to sit inside the top of the coil it will accelerate electrolysis erosion to the point where the coils is no longer serviceable.

[ed.lazda]

I had a similar problem a couple of winters back and I think it was down to condensation on the points.

[dave p]

Well, it's sorted now.You chaps were right.The HT lead terminal which pushes into the coil was rotten!
Given that this joint is covered by a tight fitting rubber boot I was very surprised at the very rusty condition of the rather cheap and nasty terminal.New parts on order, Guzzi in service for work tomorrow.

[Tim NZ]

You really should consider renewing the coil, as the coil HT Output 'tower' where the HT lead sits inside the output connection will be rotten too; like a cancer, and far worse than the HT lead was eroded.


Use a smear of dielectric grease on the end of the plug lead to inhibit any repeat occurrence.