XS250 engine test, turning over but not firing.

[Baileyxs250]

Tried testing my engine via an electric start but it's not firing. Seems to be turning over OK but not doing much else.

I did also get a flame out of the right pipe along with a load bang (backfire?) before I filmed the video.

Please click the link to see the vid on Youtube and if anyone could point me in the right direction as to what is wrong that would be really helpful!!!

Thanks,

Joe

 

[xschris]

I would check to make sure the coil wires are not crossed putting it off 180 degrees.

 

[16VGTIDave]

Check the ignition timing, and that the spark plug wires are on the correct cylinders.

 

[Baileyxs250]

Cheers guys! here is another video of flames out of the exhaust. Cheers for your help!

 

[Recreateme]

I had a situation like this last week lol It sounded fine other not firing, and the last thing it did before dying was backfire a bunch and quit..

I solved this problem by buying new spark plugs. Perhaps your plugs are no longer good ?

 

[Baileyxs250]

I just checked to see if they both sparked and only one side is sparking. I only used one plug so must be coming from somewhere else? Coil or gap in points!?

Thanks mate

 

[Greasey Fingers]

try replace the spark plug caps maybe

 

[Recreateme]

Baileyxs250 - You have to make sure they are sparking well enough... Sometimes you get spark outside of the chamber but when you put them under compression they won't spark. That was my case, i tested both plugs outside and saw sparks, but in the end i replaced them it fired right up.

 

[Baileyxs250]

Cheers,

I've had another look today, checked all the wires to and from the points, condenser and coils. I've replaced the points wires with some new ones as the old ones were looking tatty and made sure the left contact point will be firing the left plug etc and now nothing is sparking. The Coils are reading at around 3.8 and 13.2 on one coil and 4.0 and 12 ohms on the other coil? does this sound like a coil problem? I'm getting a spark at the points end (albeit quite week) but none at the plug end.
I've charged the battery and after charging it was reading 13.2v but after about 10 mins dropped down to around 12.8v...
I've checked the points gap and although not 100% perfect they seem pretty much right, I've also adjusted the valve gap too.

Could it be a battery problem? Coils? Possibly both?

Thanks again for the help!!!

 

[drewpy]

Cheers,
I'm getting a spark at the points end (albeit quite week) but none at the plug end.


Thanks again for the help!!!

Eureka! the rosetta stone has been found.

you should not get any sparking over the points, it means the condensor/s have gone ( its 2 in 1 affair and can't be separated)

 

[Baileyxs250]

Cheers Drewpy,
I managed to get it running today, turns out it was all a timing problem. Here's a link to it running, could do with idling at a slight lower RPM but still chuffed. Thanks for the help everyone!

 

[xschris]

Good to hear it's running It's always the simple things that are wrong

 

[Scorpio1963]

Cool beans sounded nice and smooth.

 

[drewpy]

nice one, but I would still replace the condensor or the points will burn out.