The JDX8 Runs!

GreenFever · Post by **GreenFever** » Fri Jan 16, 2009 12:56 am

Finally got the '75 X8 running today. Thanks to Rich and the local salvage yard. Idles and starts great but it will not accelerate. It will only move about 5mph. Doesn't sound like it is missing so I am guessing I screwed up the carb rebuild. Any body have an ideas what to look for?

The electrical issues are the ignition switch doesn't work but the kill switch does. No dash lights or tail light but the brake light works. The tack is also not functioning. I swapped the wiring harness off a '76 400 because the original one was a little tore up so I may not have got everything plugged in and grounded correctly under the dash. Some ideas would be helpful here also.

400brian · Post by **400brian** » Fri Jan 16, 2009 2:38 am

It isn't as obvious as you would think to tell if it is running on both cyls.

That said, I have found that my '74 X8 will run about 30 mph on one cyl.

If you have black goo dripping out the exhaust, it's not running on both cyls.

Check the metering lever in the carb for proper adjustment .

Fuel pick up in the tank plugged? clamps on lines? is gas going through the lines when it is running ( bubbles )?

Get the electrical issues fixed. You need to eliminate all the potential issues you can.

GreenFever · Post by **GreenFever** » Fri Jan 16, 2009 4:54 pm

I got all the electical issues sorted out but the ignition switch. I think it might just need a new one. Now that the tack is working I can see that it will only rev to 5000 with the track off the ground. No black goo out the exhaust and lots of fuel running through the lines. Plugs are a bit wet. Could it be the CDI box causing this also?

400brian · Post by **400brian** » Fri Jan 16, 2009 6:25 pm

There is a FAQ for trouble shooting the CDI system. Sounds like a good posibility that the problem lies in the stator or CDI box.

GreenFever · Post by **GreenFever** » Sat Jan 17, 2009 6:13 pm

Well it is not the CDI swapped a few different ones on there no difference. I know it is a no no but I also took the belt off just to see if the secondary or something was the problem and still only 5000rpms.

harleysportster · Post by **harleysportster** » Sat Jan 17, 2009 8:31 pm

Go back into the FAQ section that Brian mentioned and check the stator ohms. The high speed windings may be at fault.

GreenFever · Post by **GreenFever** » Tue Jan 20, 2009 8:58 pm

The high speed coil is 55 ohms. Does that mean it is junk?

harleysportster · Post by **harleysportster** » Tue Jan 20, 2009 9:09 pm

The target ohm reading for the high-speed coil is around 76 ohms. given a 10-15% difference either way is acceptable. Your reading of 55 is below the acceptable range. I would say it could be bad. Are you sure that you have both plugs firing. The best methos of checking is to use an in-line spark tester. This connects between the spark plug and the plug wire and flashes when it has spark when running.

GreenFever · Post by **GreenFever** » Wed Jan 21, 2009 12:12 am

I don't have a in-line spark tester but when I pull it over with the spark plugs out but still hook to the wires it has spark and it will idle fine. I have also swapped one of the coils with no difference. Is it possible to have spark on both cylinders at idle but not and higher rpms?

GreenFever · Post by **GreenFever** » Wed Jan 21, 2009 9:57 pm

Got a different stator from the salvage yard today. Now the X8 runs great. Just need to fine tune the carb. What should the rpms be at wot?

harleysportster · Post by **harleysportster** » Wed Jan 21, 2009 10:23 pm

Yes, it is possible for a no spark condition at high speed.

I don't know the governed rpm's but set the starting point of the high speed needle at 1-1/8 turns from lightly closed. Take the sled for a ride and turn the high speed needle 1/8 turn or less at a time either way to obtain optimum performance, then turn needle 1/8 turn counterclockwise for final adjustment

harleysportster · Post by **harleysportster** » Wed Jan 21, 2009 10:25 pm

Glad to hear you have it running.

kwc · Post by **kwc** » Wed Jan 21, 2009 10:28 pm

Keep that 440/22 close to 7000 rpm on the top end.

We need to see some pics of your sled!

GreenFever · Post by **GreenFever** » Thu Jan 22, 2009 1:18 am

Here is a pic from before I started. It looks a better now after I cleaned it up and got a better hood. Still needs a seat and eventually a full restoration.

Attachments:

Sleds_feb_mar_08_001.jpg (312.3 KB)

400brian · Post by **400brian** » Thu Jan 22, 2009 4:34 am

:suprised: Holy Lichens Batman, that sled has been sitting out for a spell! :lol22: