07-10-2011, 01:19 PM #1
99 XL 1200 LTD driving me crazy, but not fast...
I bought the ski last year with 86 hrs on it and never really ran quite right. It has D-plate, WaveEaters, PV couplers, PPK, R&D intake grate. I just had OS Bill rebuild the carbs (Thanks Bill!), and now it starts right up and runs much smoother. Took it out on the lake today and same as before, won't get above 41 mph and 5600 rpm. Out of the water, the power valves open up at 5800 rpm. Cylinder compression is 110/105/113.
I ran the test on the servo as per service manual and this is what happens; Manual says... "Install a jumper lead 4 between the black 2 and gray 3 terminals as shown. Only install the jumper lead for 1 or 2 seconds: Make sure the servomotor operates properly." What does operate properly mean? My servo will move to it's closed (neutral) position and stay there locked in this position.
Then the manual says "Note: Make sure the pulley operates three seconds after the jumper lead is removed." My servo cycles just as it does when you shut the engine off.
I am suspecting a servo problem but not sure, these things are $$$. Does anyone know what RPM the servo is supposed to open? Could it be a CDI or something in the box? getting desperate...
07-17-2011, 05:28 PM #2
Ok, no reply's so far. Since last post I've replaced the PV servo and it acts just like the original, it opens up around 5800 rpm out of the water and cycles when shut off, so I believe the original is good. Now I have discovered that the center cylinder is not firing; don't know why? I put new plugs in and ran it on water, and the center one looks like new. I couldn't tell before because I was using used plugs. I am using BR8ES-11 plugs with .39 gap as per manual. I have changed them out several times just in case a new one is bad. I checked the spark on all 3 and they all look good. The center one maybe jumps around on the electrode a little more than the others but it looks like a good spark. Compression is still good (right at 110 psi.). Carbs have been rebuilt so doubt that's the problem. What could it be? I have spark+gas+compression. Shouldn't it = ignition?
07-17-2011, 05:43 PM #3
you probably dropped a power valve had one the other day would only get 5500 rpm. What happens is the pin slides out and the valve drops and stays down, Remove the power valve covers and inspect each one to see if the pin came out and to see if the valve dropped.
07-17-2011, 08:12 PM #4
OK. I installed waveaters right after I bought it, aren't they supposed to keep the valves from dropping? Its an easy check so I'll get to first thing in the morning and report.
07-19-2011, 01:54 PM #5
I pulled the PV's out and they look ok, except for the extra gunk/carbon on them. Notice the middle one, it was fairly clean when I took it out. I suspect it's because of the unburned fuel cleaning it.
I cleaned them up and put them back in.
Since I had easy access to it, I pulled out the electrical box and tested the coils. All three of them test OK; just under .4 ohms each primary coil resistance, & 4.2 k ohms each secondary coil as per service manual. Then I tested the resistance of the spark wires. They indicate 9.9 k ohms front, 7.5 k ohms center, & 4.9 k ohms rear. From what I have read on the internet this is normal since the front wire is longer and will have more resistance.
I am still at a complete loss I still have fuel, spark, compression, and no ignition. I will swap two of the coils when I put it together and see if it changes anything, but I doubt it since the spark looked good anyway. I'm still waiting for new PV oil seals to come in the mail.
The only thing I haven't checked are the reed valves which I don't know much about. When I had the carbs off for rebuild, I briefly inspected them with a mirror but nothing more than to make sure any were not broken.
07-21-2011, 04:04 PM #6
- Join Date
- Feb 2011
Check your power valves for proper adjustment. Sort of sounds like you may be running on 2 cylinders. You sure the center cylinder is getting fuel? Check your fuel lines again be sure they aren't mixed up.
07-24-2011, 02:13 PM #7
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