2002 GTX RFI - Runs for 5 Seconds then Dies - Would Like to Hire a Specialist

[mikidymac]

To me the idle seems too low. If this was a carb ski I would tell you to just turn the idle up.

In the few seconds it does run can you hit the throttle and get it to rev at all?

I don't know how the idle is set on the RFI but your TPS could be out of wack.

It seems fine mechanically and sounds good other than the very low idle.

 

[ski-d00]

Have you checked your fuel quality as in water in the gas or bad gas? Did you try to squirt fresh fuel in the spark plugs before starting to get it to rev up like I previously recommended?

Keep it simple. With good fuel, compression, and well timed spark, it will run.

 

[kdelcar1]

Thanks for your quick responses mikidymac and Ski-d00. Mikidymac - I tried increasing the throttle several times when it ran for a few seconds but it did nothing. The throttle lever had no effect at all. Ski-d00 - I forgot to mention that I did squirt a little gas in the spark plug holes and tried it several times. This had no impact either. The starting results were exactly the same as shown in the video. Bad gas is a possibility even though it is fairly new. I haven't focused on bad gas because of the way it failed. I was traveling along a 30 mph with a solid smooth running engine, then it quit instantly. Engine just stopped like someone hit the stop button. Before it failed, the engine was not missing or stuttering. It was very smooth and powerful. Do you think a bad gas situation would behave this way?

 

[jknightg]

Have you checked the quality of the ground connection?
Try a jump cable from a clean metal part of the engine to the -ve battery terminal

 

[mikidymac]

Sure sounds like something electrical to me at this point.

 

[mikidymac]

It fires instantly. So that eliminates something mechanical or old fuel related to me. Also the fact the throttle does nothing.

 

[racerxxx]

I would have ripped the intake off already. There are 2 points where the intake is open on both ports where are and air can get in. There is not enough air but plenty of fuel. Let it sit it starts, not enough air it floods out. Let it sit it starts. At some point you need to jump off the bridge and break out the wrenches. Asking and wondering are getting no where right now.

 

[kdelcar1]

Thanks everyone! A lot of good ideas are coming in.

jknightg - I checked the ground connection at the battery and the block. Both connections are very solid. When I hold my volt meter from the + battery terminal to the block, I am getting a good 12.2 volt reading. Don't think this is the problem.

mikidymac - I think you're right about fuel. Considering that I am seeing a nice fuel spray from each injector with the fuel rail off tells me that I am getting fuel flow. I consistently get 56 psi fuel pressure at the fuel rain inlet. Also, because the engine was running great then stopped instantly, tells me that the fuel quality is probably OK. Not 100% sure on this though.

ragerxxx - I like your idea about air flow. Hadn't considered this before. My question is, if the rotary valve is turning and I am getting good compression, why would air flow be low or nonexistent? Could the blockage be in the throttle valve or air filter? What could cause this? I can see the throttle valve moving when I press the throttle lever. Also, if air flow is a problem, could the exhaust ports be blocked? Is anyone concerned about the RAVE valves? I don't mind disassembling things but I want to have some assurance that I am working in the right area before I begin.

Before I start disassembling the intake, I would appreciate your thoughts on my questions in this post.

Thanks again!

 

[ski-d00]

He's saying you may have stripped your rotary gear so that the rotary valve is not turning at all or jumped/stripped some teeth. You can stick a flexible rod through the TB and confirm that it is rotating(or use an borescope) but this still doesn't mean it's in time. Only takes like 20 minutes to take the rotary valve cover off. I suggest reading the service manual, they are free online.

 

[jts32]

You can still have good compression readings even if the RV isn't spinning. Bought a non-running ski that tested 150 psi in each cylinder, was getting fuel and had great spark but wouldn't start. Pulled the RV cover and found a bolt wedged between the RV and intake port causing the brass gear to strip. Time to dig in, open it up, and start eliminating possible issues

 

[kdelcar1]

OK, I'm convinced. It looks like my next task is to pull the RV cover. I have the factory service manual with instructions for disassembly. I'll keep you updated on what I find.

Thanks again everyone! I'll be in touch shortly.

 

[racerxxx]

You should be able to get down to the throttle body, remove it and look in. I wouldn't pull the cover. Just dis assemble the least amount you need to to get a look in there.


Just get down to item #30, the intake manifold

 

[kdelcar1]

OK, Thanks racerxxx. I'll do that first and let you know what I find.

 

[kdelcar1]

OK, here is what I found out. The rotary valve is not turning! Darn! This seems crazy because the engine actually ran for a few seconds before I removed the intake this morning. The engine ran for a full 10 seconds in the video I posted last week. When looking through the rear intake port (PTO side), I can see the crankshaft turning. I cranked it by hand and with the starter this morning. The rotary valve didn't budge. It was completely still. What now?

 

[drewski]

Is it possible that your impeller/driveline is locking up?
Never mind, didnt see the last post. Good luck!

 

[mikidymac]

Is it possible that your impeller/driveline is locking up?

No because the crank is turning

 

[mikidymac]

Your next step is to pull the rotary cover and rotary valve and check for damage. And what stopped the valve from turning.

The cases have to be split to repair the rotary gear.

 

[kdelcar1]

OK mikidymac, I'll pull the rotary cover and rotary valve next. If I don't see any problems there, the only last thing is the rotary gear, right? I assume the rotary gear is a major job.

I'm still wondering why the engine would run when the rotary valve is not moving. I'll keep you posted.

Thanks again!

 

[jts32]

If the RV isn't spinning, the brass gear is stripped. You can pull the cover for an initial inspection, but ultimately the motor will need to be removed from the ski and torn down.

 

[kdelcar1]

I was afraid of that. Thanks jts32.