QD-19

[Kriegs]

HELP. I have a QD-19. I'm have problems reading ohms on my coils and condensers. My secondary's read 7.05. My primary's read 1.0 to .9, I'm not sure what they should be at for a good working coil. My condensers read OL. I get not reading at all. I'm not sure if my wires are bad or spark plugs are bad. My motor only will run half speed at full throttle. 7.0 carb is rebuilt and working good. I rebuilt everyer thing other then power head and ignition area. Looking for any tips thanks

 

[Sunken Ship]

Have you cleaned the points? I have circled the areas that need cleaned. If cleaning the points makes the engine run good again I would replace them after that. I have circled the areas that I am talking about cleaning.

 

[F_R]

Coils readings are probably ok, if they are otherwise in good condition (no cracks, etc). A perfect condenser would read infinity on a high ohms setting. Unfortunately, there is no such thing as a perfect condenser, especially paper ones such as found in engines. So use a high ohms setting and what you see represents leakage. The higher the reading the better. This is not the same thing as capacitance, more important. You need a capacitance meter to get an accurate reading on that. "Condenser testers" give a rough good/bad indication. Fortunately, our motors are pretty forgiving.

 

[Kriegs]

The points are clean other then both have arc marks. Retested condenser they work as they should. One condenser becacame lose and was shaved by the fly wheel. Coils tested the same. Spark plug one reads 26. Second plug reads 16.3, out that be the problem. The points had metal on them from the condenser shaving

 

[oldboat1]

have a bunch of questions: getting spark on both plugs? don't know what a 7.0 carb is -- have a smaller hp carb on a 10? how do you know the carb is working good, as you put it? The throttle won't advance beyond high idle unless the motor is in gear -- running it in gear?

If running in gear at half throttle as you say, might be operating on only one cylinder -- cyl drop test is usually recommended (pull off one plug wire at a time and look for engine response -- no response means the plug isn't firing.) Gen point -- isolate symptoms, then work backwards (part. coil or set of points, for example. Check for good flywheel magnets.)

edit: If other checks OK, may simply need carb needle adjustment (check out stickies), also sync. carb and throttle.

 

[F_R]

What are those spark plug numbers? Are they resistance readings on the wires? If they are, they are supposed to be zero ohms. Sounds like you might have automotive resistance wire in there (not good). Use wire with a wire core.

 

[Kriegs]

The motor/ mph 7.0. I know the carb is working well because I had it out on the lake. Had it running as fast as the motor would let me. 7mph. Both plus were sparking. But one plug had 30.56. Lower plug had 13. I have always thought the lower piston wasn't firing. Full throttle is only 7mph. When years ago I had up to about 25 to 30 mph. Or seem to be that fast on a 12ft.

 

[Kriegs]

Do I also need to clean off the points because they have arc marks?

 

[oldboat1]

don't know what you mean by arc marks, but points should clean and bright, gapped to .020.

 

[Kriegs]

They are cloudy and burn. Like starting an arc for welding. Sorry I'm a welder so I naturaly use welding terms. Yeah I saw on my fly wheel they need to be gapped .20

 

[lindy46]

I clean them with a point file until they are shiny clean. Then clean them with a solvent, like acetone. Gap is 0.020". If they are very badly worn, replace them - they are cheap.

 

[gm280]

If you seriously want to reuse older points then you have to file them clean and smooth and make certain they close parallel to each other and flatly closed. If you have enough rubbing block remaining, then go for it. If you can clean them and deburr and wash the filings away and they close flat and will adjust to .020" , they will work perfectly again. And if the condensers don't read shorted, then more then likely they are still good also. I use a capacitor tester and check them out. Some times you can set the ohms scale on the highest setting and charge them one way and then read them the other way and get a movement out of the reading... The actually capacitance of those condensers are really small...

 

[F_R]

Normal points will have a frosty look where they make contact after running awhile. Please explain what you mean about 30.56 on one plug and 13 on the other.

 

[Kriegs]

The points have that frost look to them. They also close parallel to each other. The 30.56 and 13 where the spark plug readings. I went and got new plugs. Going to check the plug wires right now.

 

[oldboat1]

arc marks, burned,condenser shavings, frosty, shiny....confused. no spark, and trying to figure out why?

 

[Kriegs]

Shavings came from side of a condensercondenser. Arc marks I don't think its out of the norm. I think I found the problem. The spark plug wire from the lower piston has no reading at all.(bad I take it) the upper spark plug wire has a good reading. Under continuity. I will order the part asap! Then from there I guess.

 

[oldboat1]

but no spark is out of the norm. Are you not getting spark?

 

[Kriegs]

If I get a new wire for the bad one. Put everything back together. Then I will know. Should I replace both wires or should I just do one...?

 

[oldboat1]

sold by the foot normally (7mm, solid core). no reason not to replace both -- cheap. (Actually, might be a little hard to get. Local NAPA store up here has some.)

but got to press again -- Did you test for spark?

 

[Kriegs]

I have no way to test the spark. I have no way to pull the motor over. The coils are off the condensers are off. Just the plate is left.