82 rebuild road block

okay so my 1982 xj650rj seca rebuild has hit a little bit of a roadblock. I thought I'd post here in the technical section to get some feedback.

Issue 1: all the electrical wiring is setup and working with a motogadget munit and a modified simplified wiring diagram. However, I am not able to get the bike to start. The starter cranks but I'm not getting it to fire up. At the end of the day I'm reading about 11.5v and still getting the starter to turn. But not firing. I plan to check each plug tomorrow to make sure I'm actually getting a spark to each plug.

Issue 2: I did an oil change this morning after finishing the wiring before trying to start the bike and put just under 3 quarts of oil in the bike so that while on the center stand, the oil line came right up to the top of the sight glass. However at the end of the day, the oil level is now super low with absolutely no sign of a leak in the floor.


Where did my oil go?! During my rebuild I did not touch the engine except for valve adjustment and the new case cover bolts. Install consisted of removing 1 bolt at a time and installing to torque.

Other work which was done:

• Carbs rebuilt and all jets replaced.
• Rack was broken and each carb sat in carb dip.
• New o rings installed with new washers
• Carbs were benched synced before installing on the bike

The bike did run before the rebuild. Issue was a vacuum leak in the carb before the rebuild.

Thoughts? Anyone?.... Bueller?!

 

oil went into the transmission box where it belongs some went into the oil filter.

are you getting voltage at the tci ? red/white wire?

can you post your wiring diagrams?

 

Should the oil be that low still? I actually put a full 3 quarts of oil in the bike?

I'm running a setup based on this diagram that another xj user had using the motogadget.

The only different is that I'm still running the stock solendiod. Blue wire goes to start out of munit and red/white wire goes to ground.

Tci is getting power through my aux (key on) output from the munit.

 

The sump itself takes 2.6 quarts. The filter and middle gear box take the rest. If you were just changing the oil and not putting a new filter in then you would have overfilled. Unless you have a leak there is nowhere else for it to go.
The oil level is in the middle of the sightglass, so you're good, but you can top her off if you want.

The only place wher you might have a leak and not notice is a the output shaft, but a leak there is usually only a slow weeping of oil.

 

Your coils are hooked up wrong. The R/W wires (stock diagram) from both coils have to go to the TCI as well. You have them going to the M-Unit AUX circuit.

 

Just to make sure I follow, the stock R/W wire is represented by the light orange wire going from the TCI to the coils. This should have a connection to the munit as well as the TCI? (Munit supplies my key on power)

 

OK. I see the connection to the TCI now.

 

Not really related to spark but I can't seem to find a line that connects the battery +12V to the M-unit high current input terminal; it seems to dead end at the gauge on one end and at the regulator on the other end. You have to have that hooked up as you said all else was working. Just wondering as placement of the fuse between the Rect/Reg output and battery plus is important, and is even mentioned in the m-unit operating and installation guide.

 

I have the unit hooked up to a constant 12v battery. things which get a constant 12v are:

• munit
• ignition switch
• Rectifier
• speedo

the munit gets its 12v signal through the solenoid

 

So could be part of the starting issue. The starter will turn with a lower voltage, but the reduction in voltage at the coils leads to an inadequate spark. So, hopefully the battery is on the charger and when tried again make sure the battery voltage maintains at least 9.5 volts when cranking.


So the 3 red wires are electrically the same, and the bottom red is the output to the starter?




This is the main fuse I was referring to that should be placed between the battery and rect/reg. I don't see it in the above drawing. Then again, I don't see an ignition switch either.

 

The fuse on the starter is actually not in my setup. I am still using then stock solenoid. The fuse is setup between the battery and the munit and all other constant 12v items.

I'm heading back to the garage where the bike is. I'll report some updates here shortly.

Thanks everyone so far for the help and feedback

 

Good news the bike starts. Turns out I didn't actually connect the aux (key on power) to the TCI. After hooking it up it fired right up

 

So now it turns out that cylinder 3 doesn't appear to be working. The exhaust header is not hot. I've checked for spark (good) and compression (good. 1: 150psi 2: 140psi 3: 145psi 4: 150psi. I am working in an open garage with it being 100 degrees outside). Now it's onto the fuel. Currently taking a break from that (earlier reference to temperate) and rebuilding the petcock to fix the leak I previously had. No more bandaid fix of an extra on/off switch.

 

After rebuilding the petcock today and re-installing the tank the 3rd cylinder "magically" started working again. Must have been a stuck float. I'll have to keep an eye on that. Successfully got the bike to run and took it about 3/4 of the way around the block before having the push her past the last few houses. Still felt amazing to get her up and running again. Even while pushing her I had the biggest smile on the face.

After spending the day in 100 degree weather in a garage with no AC, I called it quits after that. I'll pick up later this week when the weather drops 15 degrees. I need to adjust the carbs as it idles a little too low at this point, and i feel like cylinder's 1 & 2 run a little hotter than 3 & 4.

Kind of wishing I had picked up a color tune last week...