New to the forum and need some direction from the masters. I will tell the story and maybe someone can verify what I’m missing:
BACK STORY:
Bought a used 2013 RZR 900 that was smoking and had a cold start issue about a year ago. 2 months ago I got around to ordering new cylinder, piston and rings, gaskets and timing tensioner.
Tore motor down and rebuilt top end. (Rushing to make a big ride as always). All together I still had the hard start issue but the smoke was gone. Pressed for time I narrowed the hard start to the intake valves being too tight. I didn’t have time to order new shims so I took it the way it was. I knew I would have issues but they weren’t tight enough to touch the piston. Through the weekend the start got worse and I was smoking a little which I expected from the compensation of fuel for the lack of vacuum. When I got home from the 3 day trip I tore it down to inspect the pistons, valves. Everything was okay so I reassembled and shimmed the valves.
New Problem:
I fired the RZR up and it was amazing! First time it has cranked without throttle since I’ve owned it! Then I gave it a little gas and it sounded like death. Popping in exhaust. After troubleshooting I found that the mag side is DEAD. Unplug injector with no change. Well, a little change. A few pops in the exhaust on unplug and replug. I have done everything that makes sense to a novise troubleshooter and need some advise from the RZR experts. I will list the steps I have taken to identify the problem.
-I have rechecked timing MULTIPLE TIMES (even had others verify what I already knew)
-I swapped the plugs, problem stayed on Mag side
-I swapped the plug wires, problem stayed on mag side
-I swapped the coil with a known working coil, problem stayed on mag side
-I swapped the injectors, problem stayed on mag side
-checked spark the old school way, out of cylinder touching metal and had spark
-Spun motor slowly while looking at reluctor looking for missing teeth, no luck
-Cleaned CPS and reinstalled multiple times.
-compression tested both cylinders 200 mag side 190 clutch side
-Spun motor to open exhaust port on mag side, hooked up compression hose and attached compressor hose to verify no exhaust restrictions.
-Removed air box and watched inside throttle body during quick snap accelerations to see injector pulses. look good to the naked eye. pulsing similar on each side with no "dump".
I have Air/fuel/spark/combustion with no run (what they taught us in school was a LIE!! lol)
My best friend is bringing his oscilloscope over this weekend so that we can "see inside the cylinder" but I wanted to see if anyone had any suggestions. I will post results when we find it so no one ever has to go through this again. I am beyond angry. I have eliminated/verified every part of combustion but still don’t have combustion.
