1986 xj700x no spark

My niece's 86 Maxim X has lost it's spark. According to her, when it died it was kind of like running out of gas. It died, then restarted, then lost power like running on less than 4 cylinders, and then died completely. Are there any "Common Causes" for spark failure on this particular model? When I went to pick it up for her I checked only #1 cylinder, and it had absolutely no spark.

 

First how old is battery, is it serviced to proper level with distilled water? Check fuses and connections . The X I believe still uses a TCI, check and look at plug is it melted or corroded? If no spark on none of plugs doubt it is a coil problem . What I mentioned is where I would go( one other thing Kill switch is in correct position ? just asking)

 

Got the bike into the shop, and it appears that my method of checking spark on the side of the road didn't work. I plugged in a NAPA spark tester and I do have spark. So I looked a little deeper. I could see that there was gas in the tank, but it was low so I put a couple more gallons in. I then got it to run on full choke, but as soon as I let off the choke it dies. Thinking maybe water in the gas I proceeded to drain the carb bowls. 1 and 4 only had a couple teaspoons of gas. 2 and 3 had more, but obviously not what they should have. (Petcock lever on PRI) The tank was just cleaned by a shop that I know nothing about, but they did get it running well according to my niece. She has been riding it for a couple weeks. According to her they used Naval Jelly which wouldn't be my choice, but then again there is a lot that I'm not familiar with in the realm of fixing motorcycles. I'm assuming now that the petcock is clogged with something, so off comes the tank. I'm hoping that the screens on the intakes to the petcock caught most of the alleged debris so I don't have to take the carbs off. I will also install a filter between the petcock and the carbs.

 

LOL...That Kill Switch has embarrassed me enough that it is now the first thing I check.

 

First instinct would be to point at the TCI as it controls the ignition. But it is a 30 year old bike. Which also means there is 30 years worth of oxidation, and corrosion in the electrical connections.

Starting with the handle bar controls. Make sure every contact, and connection is clean and tight. Until you know for certain that this is done. Any effort to trouble shoot can easily be side tracked by a bad connection. It will also go a long way towards avoiding other electrical gremlins in the future.

Do not think that just pulling the connections apart, and plug them back in will correct the problem. There are tiny little connections inside the switches that will need to be cleaned also. Make sure every end on every wire is shiny and bright. Use dielectric/silicone grease when putting everything back together to help keep corrosion to a minimum in the future.

Once this is done. Troubleshooting will be easier, and more accurate.

~Ghost

 

See how quickly things change. 3 comments in the time it took to type the above reply.

~Ghost

 

Sounds like Carbs, tank, petcock all need cleaned, .. Low fuel level in floatbowl could also mean float height is off.

 

Now that it is back to a running bike.
It sounds like the bike got low on fuel but didn't get switched into reserve. All that microscopic sediment/dust that settles to the bottom of the tank got sucked into the carbs. The screens on the needle valves are easily plugged by anything small enough to get past the tank filter.

As Jetfixer mentioned. A full system cleaning with the addition of an inline fuel filter.

~Ghost

 

I think maybe I "Cried Wolf" a little too early. The problem was a fuel filter that I didn't know it had. $4.36 and she's back on the road. Sorry to bother you guys. I should have checked it out further before posting.

 

No big. You had no reason to think about checking until after posting.