DT 250 Electrics Doing My Head In
Thanks to all for the replies. And thanks for sticking with me on this. I believe at the end of the day it's going to be something simple.
Well you all seem to be pointing to the condenser or wiring short somewhere. So far I haven't found anything going to earth. I see what you mean about the 3 wires soldered onto the top of the condenser. From what I can see no bare wire is touching the condenser body. But I will try insulate those wires somehow and see what we get.
Is there any way I could have damaged the condenser when soldering those 3 wires onto the top. I held it in my thumb and forefinger while soldering and the body never got too hot to hold. Just a thought.
Jesus is Lord!
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A "continuity tester" will beep with points open or closed. Some meters won't show the change accurately or at all. I find the old analog meters the best as long as they have an Rx1 scale.
Second part of this short video shows what I mean.
Hope you get it sorted - even if it is just for the satisfaction of beating the problem...……...
'69 Yamaha DT1 S
'71 Yamaha DT1 .................................. '70 Suzuki T350
'72 Yamaha AT3 . ................................... '73 Suzuki T500
'86 Yamaha DT175 ..................................'68 Fuji Rabbit Hi Super 90
'06 Yamaha PW50
'94 Yamaha TW200...
First thing is to just clean the point contacts. Even on new points (which you didn't mention if you had changed.)
And points should be grounded when closed with source coil disconnected.... you're not really clear about that.
The points systems are pretty reliable... so without knowing more about how the problem started or good pictures of how and what you're testing, it's going to be hard to help more.
Bigdog302 wrote: I rarely see source coils go bad. I would test the points themselves and make sure they have continuity when closed and infinite when open. other than that you can see if the black/white stripe wire is shorted to ground. with the ignition switches both on there should be no shorts and will only show short to ground with the ignition switches off.
another thing to try is disconnect the ignition switch wire from the throttle from the harness and checking for spark. I have seen those short to ground before. might also try a known good spark plug as I have seen spark plugs fail if they were ran a short time on the engine and left to sit afterwards. in other words a fouled plug.
you can also check the ignition coil. it should show 3 ohms with the meter connected to the Black/White stripe wire and ground on the coil itself. might also check and make sure the coil itself has good ground.
I believe that I have a problem like this on my DT250 MX 1TR6. My spark is not firing anymore. Have changed the ignition coil, condenser and the contactbreaker against new one. Then soldered the three cables on the condenser (source coul, breaker and black/white) but now I didn't have any spark fire at all. I think I have a shortend to ground anywhere in the ignition. Is it normal that I have contact from the condenser soldered point to ground when all three cables are soldered ? If I dissolder only the cable from the source coil the shortend goes off. Is it normal that the source coil is shortend to ground without a connection to the condenser ? How can I get my spark firing again? how can I test the Engine off switch ?
I had a spark before but it was weak and not on the moddle of the spark plug. I changed the ignition coil, breaker (was burned to much), the condenser and the spark plug. Points are cleaned with break cleaner.
you say: "And points should be grounded when closed with source coil disconnected.... you're not really clear about that."
It's true that I'm not really clear about that and the reason why I'm here :-)
what is the right behavior when the source coil is connected to the condenser ? When I connect the source coil to the condenser, the breaker is grounded all the time no matter if it's in closed or opened position. I think this is the main problem of my ignition or is it the normal behavior ?