1982 XJ550 Maxim rebuild

My guess is oil from the cylinder blocking the space. I put a couple tbsp of 30W in the plug holes. It held the pressure, which is all I care about. The next time the engine comes back apart the bike will be parted out.

 

Both of the ignition coils are 2.5ohms and 2/3 spark looks barely active. The book says primary(no idea which one it is) should be 2.5 but secondary should be 11k. Secondary? I do not understand that. Help? Pickup coils are 650ohms, at spec. Something is up with the ignition, unburned vapor is puffing out exhaust ports but it will not run.

 

Primary coil is the low voltage side (the connections to the TCI). Secondary coil is the spark plug leads. The secondary spec does not include the spark plug caps, so add 10K for those if you're testing with them on.

 

Well it must be the timing or the TCI. I do not know what else it could be. The cam dots were lined up to the cap dot on the long I mark for T on the crank. Carbs are primed and fuel is getting sucked in if I manually choke the carb inlet. 120-140psi avg max compression. Plug gaps are .028 and I see spark on the plugs.

 

Both secondary coils read nothing on the dmm between the plug caps and also the plug wires. Primary coils are fine at 2.5ohms. I can not even get a continuity beep on 200ohm ranging for secondary. Guess I need to replace them. Maybe the super weak spark was just not enough.

 

Did you check for corrosion on the plug wires? How did the insulation look and feel?

 

The wires feel fine and rubbery. One plug cap is broken but for most part the boots and contacts are clean and the contacts are silver-looking. I stabbed the DMM probes into the wire where the donut fits over and still got nothing. Do you unscrew the contacts out of the boots? I can nip off a little bit of wire if needed. What's odd is I was seeing spark physically on the plugs but one coil is much brighter than the other.

 

Is this a typo - you would need to be on the 200K scale to check the secondaries with the plug caps installed. You certainly are not going to get a continuity beep with that high of a resistance, even with the plug caps off your still looking at 11K +/- 20%.

 

I tried the whole scale. Nada.

 

The coils measure fine with the plug caps off. I cleaned them up and snipped back some wire. There is a spring and what looks like a graphite pin under the screw terminal. I clean up what I could and put it all back together. Same spark result, not running. I have pulled the carbs again and will be tearing them back apart. If I spray into the open boots I get fire but not on all 4. I am about to put it in storage at this point.

 

That carbon pin is the resistor. They can fail. Measure the cap separately, spec is 5 K ohms.

 

I don't get anything through the caps with the DMM. Only across the bare coil wires. I am going to order some new caps. Still, there looks to be enough spark on the plugs to fire it over.

Does anyone know what the air mix needles should be set to on the carbs? They are typically blocked off and I've not seen a spec in the book. I'm going to tear the carbs apart again and check all of the jets. I'm going to remove the intake boots and seal them with some rtv to make sure no leaks there. Anything else to check apart from the diaphrams and slides?

 

Baseline is 2 1/2 turns out from a soft seat, then tune from there. Generally you'll end up around 2 3/4 to 3 turns out.
If your idle mixture screws are still factory capped you'll want to replace the o-rings for them.

 

I did that already during the rebuild. I set them to 2-1/2 so I dunno what's going on unless there's a major air leak on the boots or the carbs just aren't feeding properly. I have the YICS eliminator pushed all the way in and both capping bolts in so that should not be an issue.

 

Try turning them out a bit more. The YICS being blocked will eliminate the supplemental fuel that comes from the three non-firing carbs. That has the potential to make it lean enough that they won't fire at the baseline setting.

 

you can get a crude running sync with just the starter, be quick and don't abuse the starter. and with that silly yics tool in you should see a major vacuum leak

 

OK, I'll try that tonight. The YICS eliminator was out initially and it still would not start up on all 4. I'm going to check all 4 diaphragms and put the carb set back on with 3 turns on the idle mix screws. #3 stopped peeing out after the fuel unstock the float.

 

It will run full tilt if I manually choke the carbs. I got fuel flowing through but I suspect the idle circuits are clogged. Not what I wanted as a result of the rebuild.

 

30 mins with the bowls off, carbs back on.

 

She sounds goooood.
Do a running synch to dial her in (after you have the exhaust back on) and you're golden.