Also, we have tested the pulse generator and it is good.
1988 TRX350D no spark
We recently purchased a Foreman 350 that did not have spark. We have replaced the CDI, ignition coil, and the stator. I have tested for continuity on every wire I can think of as well as cleaned and checked all connections. I also have grounded the neutral safety switch. When we bought it, there was some sort of relay hooked into the fan control box that was jumped to the oil temperature sensor that would turn the fan on when the ignition was turned on, but the oil temp light is not turning on when the ignition is switched on. Could this still be causing it to not have a spark? And if not, what else could possibly be the problem? I have scoured the forums for ideas and tried every idea I have been able to find with the exception of replacing the oil temp sensor and I am at my wits end. Is there any other recommendations or is there any thing I could be missing that might get this thing to fire? Thanks in advance!
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Step by step;
I take it you have power to the accessories and the starter motor turns the engine?
The ignition gets it's power from the pump fuse - do you have 12v on the black/white wire at the CDI unit?
I take it you have power to the accessories and the starter motor turns the engine?
The ignition gets it's power from the pump fuse - do you have 12v on the black/white wire at the CDI unit?
The starter is turning, but I do not currently have the spark plug in because we keep testing for spark. I am a little confused about the 12v at the back wire. When I have the multimeter on V~-, I get readings with the kill switch off but not on. When I have the multimeter set as if I am testing battery voltage, I get 12.5v roughly with the kill switch on but not off. I am not sure which is supposed to be the correct way to test it. I am assuming that it is as if I am testing for battery voltage because that is the only way I get a correct reading. I have gone through the repair manual and tested for resistance at the Bl/Y and G/W for ignition coil and primary coil, and Bu/Y and G/W for pulse generator and have tested the pulse generator for voltage when the starter is cranking and have gotten voltage there as well. I set the ignition to on and and engine stop switch to run and tested the Bl/W (+) and G/W (-) and got the 12.5v when set as if I am testing battery voltage. I made sure I was in neutral and tested Lg/R and G/W for continuity and had it. I tested Y and G/W and had no continuity as listed in the manual and the Y and Y at the regulator/rectifier had continuity coming from the CDI side as listed. I have started checking all of my grounds and so far I have not found any with a bad connection but I still have a little more to go on checking those.
On the 88 model, you need to unplug the rec/reg and then check for spark - on the 88, if the stator shorts to ground, it can kill the spark
Ok, I unplugged the rec/reg and tried again and I am still not getting spark.
OK - well that just eliminates the stator as a potential problem - now it get's technical, you need to get a peak voltage meter to check the output of the pulse coil, CDI unit and primary coil.
I am going to see if I can get my hands on one. What ranges am I looking for on each output? Am I recording results as I am hitting the start button and turning the starter over?
Yes - as engine cranks
3-5 volts on the pulse coil wires
100 volts on the wires on the coil
About 30,000 volts on the spark plug wire
3-5 volts on the pulse coil wires
100 volts on the wires on the coil
About 30,000 volts on the spark plug wire
I am still working on finding a meter, but I have a couple of other questions. Should the starter still be turning if the kill switch is set to off? Also, there is a relay from the fan control unit to the oil temperature system wire, I am assuming the oil temperature sensor is bad and the fan was not cutting on when it was supposed to. Should I have that hooked up when I am trying or is it unnecessary?
Actually I just wanted to let you know it's running! I had a dirty ground to frame, cleaned it up and checked all of my other connections, turned it over and got spark! Need to do a little work with the fuel pump now but she's running! Thank you for your help!
In many of my other posts I stress; 90% of all electrical problems are caused by poor connections and 90% of poor connections are ground connections - sorry, I missed stating that early in this post.
I had stated that I had checked all of my connections, I just hadn't found anything yet and was starting to think I wasn't going to in that regard which is why I was asking for help. I just ended up overlooking one. Your other posts are the reason I started checking them to begin with. Thanks again!
Hello I have almost the same problem. I had problems with fuel pump, got it fixed. Got it running, after installing pump, it stoped and had no spark. First I thought that cdi was broken, ordered a new one but nothing... still no spark. Where was this ground cable located?I had stated that I had checked all of my connections, I just hadn't found anything yet and was starting to think I wasn't going to in that regard which is why I was asking for help. I just ended up overlooking one. Your other posts are the reason I started checking them to begin with. Thanks again!
Where was the ground that that was your problem?Actually I just wanted to let you know it's running! I had a dirty ground to frame, cleaned it up and checked all of my other connections, turned it over and got spark! Need to do a little work with the fuel pump now but she's running! Thank you for your help!
I have the same problem, same year and model. Where is that ground located? June 3 2023Where was the ground that that was your problem?
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