96 challenger motor coughs at higher speed

[LindaP]

When I increase the throttle a little past idle,the motor
coughs very badly, will not accelerate and sounds
like the motor will break if left at that speed. I just
replaced the plugs and cleaned the spark arrestor screen.
The plug wires were changed by the prev. owner recently.
The motor runs very smooth at lower speed. The pump
is giving a nice water stream and exhaust also gives water.
I am pretty handy, and need to keep costs down.
Help.

 

[seadoosnipe]

Backfire?

It could be several things causing the backfire. Most likely, will be the rotary valve. Either out of time or sheared the key.
There is some possibility of the carbs running out to lean. According to the trouble shooting section in the manual, to lean can cause backfiring.
Having an older model Doo myself (1997 Challernger) it's pretty important to have the shop manual available for reference, since with age, comes minor and major work. Mine was kept in the garage and is in excellent condition but has required some major repairs, which I have done myself. If you have any mechanical apptitude, there a pretty easy engine to work with. But the shop manual and the desire to read and learn is the key to a healthy motor.
Good luck!..............:cheers:

 

[LindaP]

96 challenger coughs at higher speed

Hi, Thanks for the info. I think your right on the valve.
I took them apart, previously and seperately, but didn't know of an adjustment. I only removed the top and the rubber seal, not the metal baffle in the motor. Also I noticed a trickle of water from the valve on the exhaust,
probably from my bad reinstall. Could this cause the prob?
The motor is like a mower that is starved of air about to stall, but its not backfiring.

Thanks very much for your help.
:agree:

 

[LindaP]

1996 oil injection system missing in action

The previous owner did away with the oil injection system
altogether. There is nothing left but the tank and it doesn'
connect to anything. How are my valves that you mentioned getting the oil?
Thanks

 

[Wheels & Waves]

You are working on the RAVE valves and not the rotary valve. If you are getting water leaking from the water regulator (valve on water box in exhaust system), you may need to replace it as it is not repairable. This valve controls the exhaust temp and will cause a poor running condition if not working properly. You also need to completely remove the RAVE valves, including the valve itself, and clean. You should replace the o-rings on the valve stem if they are hard or loose. Dirty RAVE valves will also cause poor running conditions. Also, check your charging system while running. You should have at least 13 volts at the battery when running. Just a few areas to check first.....

 

[Wheels & Waves]

Let's hope the previous owner at least left the oil lines to the rotary valve bath chamber connected and full of oil. The Rotax engine has a rotary valve plate that rotates infront of the fuel intake at the engine case. This valve is driven from a shaft off the crankshaft. There are two lines that need to be connected to the engine. If they are still there, they will be clear with one going to the bottom of each side of the engine. Chances are that they left them connected, just removed them from the tank and filled with oil and pluged off. If the lines are not there, that would explain the problems you are having as if the rotary valve shaft is not lubricated, it will fail and you will have to rebuild the entire engine to fix. Check what is there and get back to me here or via PM.

 

[seadoosnipe]

Wow!

Good description Linda. I hope it's not to late, but as Don said, this is probably going to be the root of your problem. Look into Don's request and let us know. We'll be eager to hear what you find out.
BTW, great reply Don!...
Louis

 

[LindaP]

Rave valve total removal for cleaning

Hi Guys,
I t was dark when I got home from work, but I am anxious
to see if oil lines still run to both sides at bottom of motor.
Will let you know.
I have removed the top of the Rave valves, but don't see
how the shaft removal is done. The manual does not
explain how to remove, just shows a pic. I would like to
clean them as you suggested. Can you explain the proc.
for me?
Thanks Much
LP

 

[seadoosnipe]

Rave valves

Linda, it sounds like you've taken the caps off the rave (rotax automatic variable exhaust) valves and exposed the bellows. Not much to do there. You need to undo the two allen head screws, one on each side, and carefully slide (so you don't break the gasket) the complete unit out. Once out, you can take a little carb cleaner or degreaser of some sort and clean off all the carbon deposits. The rave on the Magneto side is easier removed by popping the cap and unscrewing the bellows with a metric socket so that it will clear the exhaust housing as you try and slide the valve out.

 

[LindaP]

96 challenger coughs

Hi, I removed and cleaned my rave valves, they were
covered in black. I noticed that where they came out
is very black also. How is this cleaned or not? I have not
reinstalled them yet, waiting for new gaskets.
I also discovered that the wear ring around the prop. is
badly worn on one side. The prop looks ok. I am going
to need some advise on this job also.
You are all great, love you seadoo guys.
LP

 

[seadoosnipe]

Slides?

The slides on the motor side? Don't worry about them. If you do, you'll be knocking debris into the top of your cylinder heads.
The wear ring,........I just did a post on how to remove the wearing ring. I think it's in the PWC side. When I get the time, I'll PM you on it's exact location. The post even has pix of an impellor and a destroyed wearing ring.
If your really going to be getting your hands dirty working on these motors, it would really be wise to have a manual to reference. We'll always be here to assist, but when you work on it yourself, you'll understand a lot more, following the steps it takes to do the work. When you get stuck, come on it and ask us!...
BTW, we offer the manuals online here in the premium section where not only do you get the manuals, but it opens the door to the premium forum, for questions and answers.
Good luck, and no matter what road you take, the forums members, including myself will try and help best we can.