Tuesday 28 February 2012

More Issues... Solved!

I guess I jumped to conclusions. 

After letting the engine run for a while, (probably 15 minutes), the smoky exhaust pretty much went away. I did a compression test once everything was warm and came up with good results. 135 psi. So I guess everything is OK. The smoke could have been a result of the top end rebuild. I thought I had already ran the engine enough to burn off the oil, but maybe not. I suppose the smoky exhaust could also just be caused by the cold temperatures (-5C in my garage) and the cylinder/piston having a loose fit until everything gets really warm. I'll start it up again on a cold day and see how smoky it is.

I also checked out the reverse issue more closely and found that it was just a sticky cable. The spring wasn't returning the lever all the way back, so the reverse switch thought that the knob was still turned. The cable is lubed up and now it works perfectly. Now you have to hold the knob while shifting down to get into reverse. You still don't have to apply the brakes, but that may not have been the original procedure either. (?)

Now the only things left to fix are the front wheel bearings and brakes.

Wednesday 22 February 2012

More Issues

Well... now that it runs, a few more issues have popped up...

It's pretty smoky once it gets warm. I will do a compression test soon which should determine if it needs new rings. If the compression is OK, then I guess it could be valve seals. (?)

I also noticed that I can shift into reverse without pressing the rear brakes or turning the reverse knob. I haven't investigated the cause yet. It's probably something that should be fixed to avoid accidentally popping into reverse while moving forward and blowing up the transmission.


It's ALIVE!!!

IT RUNS!! After all that, it was the pickup coil causing the grief, even though the tests showed that it was OK. (??)



New stator and pickup coil. (Comes together in the same wiring harness).

Old stator & coils.
New CDI. (Now I have a spare).

New ignition coil. (Also have a spare now).

Putting the side cover back on.

Wednesday 15 February 2012

New Parts - An expensive way to troubleshoot

- Tried a new CDI. ($220) - Nope. Still have intermittent spark. No returns. OUCH!
- Tried a new ignition coil. ($40) - Nope.
- Ordered a new stator/pickup coil. ($100) - Arrived in the mail today. I'm going to try it tonight.

As for total spending on the Big Bear, I'm still below what I would be able to sell it for (running), so I'm not too concerned. Let's just hope not too many other problems show up!

If the new stator/pickup coil doesn't solve the problem, then I guess the only thing left is to rip apart the wiring harness, which I really don't want to do.

In the back of my mind, I'm still a little concerned about the timing being off slightly. But I guess I'll worry about that after we get it running. 

Testing

Well... we've tested all of the components in the ignition system individually, and everything checks out fine:

1.) Spark plug - new, gap set (0.6~0.7mm)
2.) Boot - (10k ohms)
3.) Primary coil - (0.36~0.48 ohms) - checked between orange wire lead and coil base
4.) Secondary coil - (5.44~7.36k ohms) - checked between orange wire lead and spark plug wire
5.) Engine stop switch - continuity between B/W & B
6.) Main switch - continuity between B/W & B
7.) Pickup coil - (459~561 ohms) - checked between W/G & W/R
8.) Source coil - (270~330 ohms) - checked between B & G
9.) Peak voltage output of both pickup coil and source coil - no specs but they seemed OK
10.) Wiring connections - checked for continuity end to end and between ground on all wires related to the ignition system. Everything looks OK.

Soooo.... now what? 

Electrical Problem

Something on here is causing weak & intermittent spark.