Pls Help! Bizarre 951 Problem!

[gwg2580]

Ok.. I bought a '00 RX (951 carb) from someone used. I'll admit he was a bit shady so I wouldn't be surprised if he hid something from me. I took the ski out for the first time friday and ended up getting towed in..and i'm stumped! heres what happened:

It had no battery so I installed a brand new batt, new gas and plugs. At first it ran great out of the water on hose, then in the water it was bogging down and stalling at low throttle, If I feathered the throttle a bit it got alot better. So, then it's running good, with an occasional spit n sputter so i'm thinking ok great i'll just tune it up a bit, clean the carbs, etc and i'll be fine for the summer. I did some tricks, did a couple of wide open runs, and on the last run it died. No noises or anything just a quick slow down and stall, then wouldn't start. I assumed the battery died from the earlier stalling I was having. I got towed and brought it home. It mimicks the exact signs of a bad battery but the batt is new and tested fine. Each time I try it, the 'maint' warning flashes and it cranks very slowly several times as if it doesnt have enough voltage then just beeps. Its totally drivin me nuts as its the exact same as a weak or dead batt, when I know the battery is fine. I tried jumping it and got the same results, just turns over very weak and slowly for a few min til it gives up and beeps. The impeller is free of any debris or blockages.

I was supposed to be taking the wife out the day after my 'test run' and thats not happening now and shes upset. Ugh! lol... Any help you guys can give would be appreciated greatly and i'll answer any questions you have to try and troubleshoot this, saving my investment!! I noticed a post on here from <slipperywhenwet> with similar issues and someone mentioned a bad starter?

 

[PWCdoc]

Take the spark plugs out and tell us what it does when you try to turn it over. Also, do a compression check if you can and let us know what the results are.

 

[fireball451]

Don't ever jump start!!
Replace grey fuel hoses, clean and rebuild carbs, clean fuel valve.
Fuel system cleaning and hose change is a given.
Hope you haven't seized the motor.
Previous post is a good place to start.

 

[Chester]

Jump start is OK as long as you don't jump from a running vehicle.
Just be very careful because if you have any gas fumes in the hull, a spark will light it up. KABOOM!

Chester

 

[PWCdoc]

:agree: and before you start replacing things, lets try to figure out what was the cause of the problem first. Don't assume it's the fuel lines or anything else yet. Give us more data and we'll narrow it down. That way when the problem is corrected you won't have to worry about having that last little doubt in the back of your head.

 

[gwg2580]

I agree.. i'd rather try and start with smaller things rather than crackin the head open if not necessary. I dont have a compression tester unfortunately. I wont for a bit unless they sell them at an auto parts store. I checked the fuel filter, cleaned the switch and pulled the valves today to get a small peek inside. From what I could see the pistons, rings, walls seem ok, no damage or metal found. I cranked it by hand and it moves. Just the rear plug fouled up a bit more and the rear valve was loaded with gummy black oil restricting its movement a bit. The fuel delivery/carb theory is on my mind but.. Its very bizarre how it mimicks a dead battery, crankin real slow a few times then nothin. *One little thing I did notice--when you hold in the start button it isnt an completely constant crank.. almost like it pauses a second in between each. My only guess at this point is that it stalled from dirty carbs like it had done in the beginning then the starter went bad.. any ideas?

 

[ski-d00]

check connections and ground at motor, does it turn over fast with the plugs out(wires on the grounding posts, of course). brand new fully charged battery, correct?

 

[gwg2580]

heres where im at so far.. I cleaned the valves since they were caked with crap, it has spark, turns over well (from what i can tell) without the plugs in. I tried it again with the plugs and it wont fire at all. I got a msg on the display saying "ENGINELI" briefly. Today it acted like a car thats flooded and you keep crankin n crankin til finally it sputters to a rough start... tho the battery wont last long enough to keep crankin.. At times it seems like it wants to start, gets goin pretty quick once in a while, shudders a bit then dies. Im no expert but do you think fuel prob?

 

[PWCdoc]

Do you have a good full charge on your battery? Try changing the plugs out.

 

[gwg2580]

well the plugs do have spark.. theyre new and were used just for that first hour of riding i got in. the battery is brand new just wont last long with all of that cranking..

 

[sony224422]

you can foul plugs quickly and randomly.. 2 strokes love to eat plugs!

 

[gwg2580]

oh def.. i always carry extra plugs and keep them as new as possible.. tho i DO have good spark with these.. im guessing its a fuel issue at this point..

 

[PWCdoc]

Check your voltage on your battery and let us know what reading you are getting.

 

[gwg2580]

Well... I found out the problem! I have never seen anything like this before in my experience tho! When you take the caps off the rave valves on top of the block they should move freely with the springs, well one of them was sluggish so i pulled both to clean them. The sluggish one was caked with deposits and was rubbing the wall pretty bad. Apparently to the point where it was hanging up and being struck by the piston. The top of the piston is chewed up just a bit along the edge above the ring (not to the point where it would make a huge diff) and the valve is still tight moving up n down inside. Any suggestions on how to attack this?? Id like to try and smooth the walls inside since theyre not really damaged just little nicks in them and fix this without buying a new top end. Definitely a new one for me tho.

 

[ski-d00]

did you check compression? if not, you should, that will tell you a lot. then take the head off to evaluate properly. the rave valve should never hit the piston regardless of its position or how caked up it is. I've seen that many times and usually does quite a bit of damage to the rings/piston/cylinder wall and a new top end is in order. Many times, people forget(or don't know they should) to grind the rave valves back after a cylinder is bored out and bam, that's what happens. Are you sure the piston is hitting the rave valve?

 

[gwg2580]

yep.. the marks on the top of the piston are right where the valve is. theres a couple of nicks in the valve and the piston is dented up a bit on the top. the cylinders werent bored out but apparently he was messin with the valve. you can unscrew them, i found it was loose so i tightened it. he must have unscrewed it a turn or two and it was entering the cylinder. even if i do just a top end rebuild.. my only hesitation is..with my last 951 rebuild.. i found it nearly impossible to remove the head without pulling the whole damn engine..

 

[rexsteiner]

I think you should try to get us some pictures. I've heard of this happening on polaris engines and yami's. But not often on doo's.

 

[gwg2580]

I guess to summarize.. the valve was loose.. and gummed up. The valve being so gummed up caused it to drag, stalling my engine and diff to start, then hitting the piston after i cleaned it and it was free moving again. Here's a pic of the valve and a couple of the piston.. best i could do with trying to hold a light in there and a camera lol.. they screw into the valve housing and he must have loosened it. i cleaned the valve and re-tightened it and everything works perfect now just concerned about the piston. im sure it would work but prob not the best.

 

[rexsteiner]

i would deffinatly check your compression. it almost looks like something got in there like a locator pin or something. if it just nicked the valve and the piston skirt is a little scuffed and the ring is fine then consider yourself lucky but any that i have seen that drop a valve usually either break the valve in half or damage the piston severly.

i had a friend once on a polaris engine break a caged wristpin bearing and 1 single needle fell out and ended up on the top of the piston. getting samwiched between the head and piston about 50 times. it would probably be wise fro you to pull the head also.

 

[gwg2580]

yeah.. popped the head cover off and the only damage is whats in the pics.. just in that little spot where the valve slid down hitting it. the rest of the piston head is ok. the valve has a slot in it to keep it from turning, and you have to push down to tighten it. apparently it wasnt screwed all the way in before and was one turn out. def lucky. im thinking the compression will be ok since its above the rings. im just irritated that it took so long to figure out..lol.. the valve being so gummed up caused it to stall out then be tough starting.