Riddle me this.... 06-800P-tek Summit
- Thread starter Shibby!
- Start date
Had a similar problem on an 04 800 few years back - RK tek piston kit installed 5 ride previous> sled ran great day before - next morning going up the trail notcied tinny / rattling noise - sound like exhaust spring rattling - stopped sled and engine . opened side panels and check for loose springs,etc ?? Couldn't find any broken or loose springs . restarted engine revved engine a bit -slit rattling noise - thought maybe something under engine that I couldn't see . Drove maybe another km up the trail - noise got louder - shut engine off - turned out to be a failied rod bearing. I think if your engine was on its way out it wouldn't get better or sound better in my opinion. It very well could have been detonation , some bad fuel , maybe the solenoid.what about a fouled spark plug. With the amount of km on your engine it would not be a bad idea to check things over.
- Thread starter
- #23
Posted on "rebuild parts" and on Dootalk. This is more of my trouble shooting thread though..
Alright!
Back at it again. Got a chance to get out to the garage and tool around for a bit. This is what I did:
1) Checked the DPM switch with 9V battery. Works flawless.
2) Decided WTH, lets take the head off.
This is what I found:
Mag side piston:
Clutch side piston:
Looking a little closer..
Mag side piston/cylinder:
No wash here!
Clutch side cylinder:
Oh oh...
Alright!
Back at it again. Got a chance to get out to the garage and tool around for a bit. This is what I did:
1) Checked the DPM switch with 9V battery. Works flawless.
2) Decided WTH, lets take the head off.
This is what I found:
Mag side piston:
Clutch side piston:
Looking a little closer..
Mag side piston/cylinder:
No wash here!
Clutch side cylinder:
Oh oh...
- Thread starter
- #24
Clutch side Piston:
Questions:
1) What could have caused this. Seems awfully odd the major points of damage are across the cylinder from each other, yet the ports look ok. What did the engine swallow?
2) Is this the rattle I heard, or an existing problem and the rattle I heard was indeed the belt previously mentioned? Odd that they happened both the same day.
3) Plan of action? First I'd like to know what might have went through my engine, and b, from here on it's a top end... and?
Thanks in advance for the help guys.
Q
Questions:
1) What could have caused this. Seems awfully odd the major points of damage are across the cylinder from each other, yet the ports look ok. What did the engine swallow?
2) Is this the rattle I heard, or an existing problem and the rattle I heard was indeed the belt previously mentioned? Odd that they happened both the same day.
3) Plan of action? First I'd like to know what might have went through my engine, and b, from here on it's a top end... and?
Thanks in advance for the help guys.
Q
- Thread starter
- #25
What's the opinions here?
I've never had damage like this before, but I'm leaning towards a ring.... Is it possible or common for a rod bearing to lose it's needles?
Thing is, whenever I seen damage like this on other's engines, usually the head takes a lot more abuse. Like peices of metal stuck in the head adn big chunks taken out. Mine is relatively untouched with only some very, very minor dents.
I've never had damage like this before, but I'm leaning towards a ring.... Is it possible or common for a rod bearing to lose it's needles?
Thing is, whenever I seen damage like this on other's engines, usually the head takes a lot more abuse. Like peices of metal stuck in the head adn big chunks taken out. Mine is relatively untouched with only some very, very minor dents.
whole_control
Active member
ok kids... I have to agree with my friend Steve = Slamnek. Also im a closet case geek... so here is an interesting article that I read awhile ago... help me help you! lol...
Engine Basics: Detonation and Pre-Ignition by Allen W. Cline
Engine Basics: Detonation and Pre-Ignition by Allen W. Cline
- Thread starter
- #28
Sure the plug looks a little white and head/piston a bit clean, but IMO, it doesn't look like bat detonation if it were.
What looks more like detonation is the "pitted" or area by the exhaust port. Those big "chunks" on the edge of the piston don't seem to go with that story.
Then again, maybe the knock sensor was telling it to retard the timing and hence the shitty running.
Problem here is where is the extra air coming from? Bad gas ending up with clogged jets? Engine pressure tests ok so the seals on the crank should be good.
Temperature was warmer so more oxygen = leaner, but the other piston looks nothing like a lean jetting =)
Noticed the exhaust port pitting when really zoomed in so maybe the pipe flange is leaking a bit? The one bolt backs out, but the others remain good. I snugged the bolt up for the pressure test so maybe when it was loose it was seeping air in?
No crack in y-pipe with pressure test on Y-single port plugged.
Can somebody confirm this is detonation and not a hungry engine?
davelaw1982
Active VIP Member
Yup, detonation on clutch side piston... You have damage on the exhaust side and on the very edge of the piston! Have you looked through the exhaust ports at the skirt of the piston yet, or to see the ring and ring land of the piston? Did it damage the jug at all near the exhaust port, flake/chip the nikasil at that point? If your exhaust gaskets are loose or if your doughnut on the Y pipe to the pipe is leaking, you can cause a lean condition on that cylinder. With the color (white) of the piston on the exhaust side of the piston, I would be thinking exhaust leak on that cylinder.
For the wrist pin to loose a needle, you would have to loose a snap ring and one of the two washers on the side of the con rod would have to fall out to allow the needles to move around and fall out.... There are 25 needles in a cageless bearing FYI.
I don't know what to tell you about the pitting on the head, as mine had some of this, but there were no signs of detonation anywhere on the pistons when I pulled them out. If you need, I have two stock pistons in great shape, just need new rings on them and they would be good to go. If you do a top end, install the caged rod bearings from an 08-09 engine, same fit, just no messing around with the cageless ones and the installer tool.
mxz sledhead
Active VIP Member
not sure if you check all ready or not but check carb boot at the base of the reed .I had that problem on mxz 800 it was on a fresh rebult top end and i check them before i put engine back to together
tex78
Active VIP Member
bad reed boot, bad fuel, exhaust loose, carb junk will cause lean in that cylinder
MoFoREVxp154
Active member
In my profesional opinion. Pull out the crank and check to see if the inner bearing seal poped out. Something went through the engine... Probably a piece of seal. Not enough damage if it was metal.
- Thread starter
- #34
Well I'm back at it again.
1-2 months of sitting in my garage in peices and this recent snow and a trip to the overpriced ski hills has me wishing my sled is up and running.
So, where I'm at right now:
- Engine cylinder is off and bottom end still in sled.
I have to take the primary off (water in shaft technique), and disconnect the oil line and coolant line.
I am going to pry this clamshell apart and see what goodies it has in store.
What I'm wondering is once apart, other then the following, what do I need to re-repack with ISOflex grease, assemble, and seal this pig up.
- loctite 5910 for the two bottom end halves,
- loctite 243 for the bottom end bolts
Should I replace the seals, or are there any other seals that need sealant when assembling the two halves? If so, does somebody have part numbers so I can get them on order?
I'll be doing the pistons with MCB Performance dual ring pistons, gaskets, and caged bearings. Making sure to check the squish before installing the head.
My ultimate goal is to test before I leave on a trip in February. If not by, have it assembled and tested shortly after I get back in Early March.
I appreciate the help!
1-2 months of sitting in my garage in peices and this recent snow and a trip to the overpriced ski hills has me wishing my sled is up and running.
So, where I'm at right now:
- Engine cylinder is off and bottom end still in sled.
I have to take the primary off (water in shaft technique), and disconnect the oil line and coolant line.
I am going to pry this clamshell apart and see what goodies it has in store.
What I'm wondering is once apart, other then the following, what do I need to re-repack with ISOflex grease, assemble, and seal this pig up.
- loctite 5910 for the two bottom end halves,
- loctite 243 for the bottom end bolts
Should I replace the seals, or are there any other seals that need sealant when assembling the two halves? If so, does somebody have part numbers so I can get them on order?
I'll be doing the pistons with MCB Performance dual ring pistons, gaskets, and caged bearings. Making sure to check the squish before installing the head.
My ultimate goal is to test before I leave on a trip in February. If not by, have it assembled and tested shortly after I get back in Early March.
I appreciate the help!
jackinthebox
Active member
I agree with MOFOREV telling your center crank bearing is pooched.srry man ,my thoughts anyway you can read my article in another thread similar stuff.mY MOTOR HAD 3300 hard MILES when it started acting up.I didnt have deto like that but i had bad scoring on cylinder walls(mag side) and such,not real bad but bad enough..that when the clam shells were knocked apart the center bearing was just F'D......yOU SHOULD HAVE CHECKED YOUR CRANK RUNOUT TO BOOT before taking jug off.
- Thread starter
- #36
Is run-out the up and down movement of the crank? If so, why would the cylinder affect that? I know I need a stand and guage, but that's a tool I also don't have.
I guess we'll see when I split the case.
- Thread starter
- #37
Ok guys.
Hope the help is still being offered. I've withheld this info for awhile to see what others come up with and just use it as information.
When I slipped the head off I found the clutch side piston to be missing maybe 2 square inches of piston skirt. Just gone. My original thoughts were correct except it wasn't a ring or a reed valve, it was a chunk of piston it swallowed and spit out.
The good news?
I'm 100% shocked there isn't any damage. Aside from the pistons, I have yet to find any nick in the cylidner, crack, or dent. The cylidner is 100% perfect. Unreal. It was maybe 10-15 seconds of rattling before it spit it out.
The bad news?
I have yet to investigate the bottom end. I really don't want to split cases, but figure its as good as time as ever to pay the rediculous amount of money for ISOflex grease and Loctite sealant for the cases. This way I can ensure the bearings are chilling in fresh grease. I *hope* I don't see any damages, do the quick grease job, seal the sucker up, slap it back in and have a fully functioning BRP again!
Some guys mentioned Precision out of Edmonton had the grease for 30$, but they must have caught wind of the BRP's pricing and bumped it to 60$. Anybody else have a line on ISOFLEX that's more realistic to the 18$ it actually costs dealers?
And for further debate. Some switch from the overly expensive Loctite gasket sealer to Yamabond. The manual say's they'll slap your pee-pee for doing this. Those who have done it say absolutely no issues. The Yamabond is approx 1/10th of the cost of this Loctite and designed to the same thing.
Additionally, I'm not 100% sure this was a freak accident. Did the piston run lean causing it to overheat and crack a stressed piston? Was there play in the wrist bearing? Is the wrist bearing still there? (I haven't looked), was there some piston slap from the big end bearing?
All these will be answered better if I just manned up and dug the engine out of this sled, so starting next week my other project gets shipped to Arizona, so I can start toying with the sled and ordering parts for my return and quickly putting it back together so I can get some ride days in and some quality back country powder on the board.
Hope the help is still being offered. I've withheld this info for awhile to see what others come up with and just use it as information.
When I slipped the head off I found the clutch side piston to be missing maybe 2 square inches of piston skirt. Just gone. My original thoughts were correct except it wasn't a ring or a reed valve, it was a chunk of piston it swallowed and spit out.
The good news?
I'm 100% shocked there isn't any damage. Aside from the pistons, I have yet to find any nick in the cylidner, crack, or dent. The cylidner is 100% perfect. Unreal. It was maybe 10-15 seconds of rattling before it spit it out.
The bad news?
I have yet to investigate the bottom end. I really don't want to split cases, but figure its as good as time as ever to pay the rediculous amount of money for ISOflex grease and Loctite sealant for the cases. This way I can ensure the bearings are chilling in fresh grease. I *hope* I don't see any damages, do the quick grease job, seal the sucker up, slap it back in and have a fully functioning BRP again!
Some guys mentioned Precision out of Edmonton had the grease for 30$, but they must have caught wind of the BRP's pricing and bumped it to 60$. Anybody else have a line on ISOFLEX that's more realistic to the 18$ it actually costs dealers?
And for further debate. Some switch from the overly expensive Loctite gasket sealer to Yamabond. The manual say's they'll slap your pee-pee for doing this. Those who have done it say absolutely no issues. The Yamabond is approx 1/10th of the cost of this Loctite and designed to the same thing.
Additionally, I'm not 100% sure this was a freak accident. Did the piston run lean causing it to overheat and crack a stressed piston? Was there play in the wrist bearing? Is the wrist bearing still there? (I haven't looked), was there some piston slap from the big end bearing?
All these will be answered better if I just manned up and dug the engine out of this sled, so starting next week my other project gets shipped to Arizona, so I can start toying with the sled and ordering parts for my return and quickly putting it back together so I can get some ride days in and some quality back country powder on the board.
- Thread starter
- #38
Kluber Isoflex Topas NB 52 Snowmobile Grease
Hum... I'll have to double check but that appears to be the same stuff...
Hum... I'll have to double check but that appears to be the same stuff...
- Thread starter
- #39
This is the BRP stuff.
You can buy it from them and they ship to Canada via USPS (no duties). Here's what they quoted me yesterday:
"$31.95 incl shipping to Canada via US Mail, we have them in stock. We accept credit cards and paypal: advanced_machine@sbcglobal.net."
I will be ordering from them next week. Screw 100%+ mark-up these other stores are selling it to us for.
Loctite 5910 is $57.69
Looks like I'll be ripping out the bottom end this weekend.
- Thread starter
- #40
Sled is back together and running strong. Went out sled boarding last weekend for it's breakin. Had a great time.
I do have an air leak to track down as it idles up. I pressure checked engine before top end was done and it pressure checked much better than when I reassembled. Was bubbling out of the Y-pipe bolts/flange area a bit, and gasket area on the reeds. I'll double check before applying RTV to the gaskets, which don't seal worth a damn. Hope that fixes it. Never had it idle up before with the choke drop fix.
I do have an air leak to track down as it idles up. I pressure checked engine before top end was done and it pressure checked much better than when I reassembled. Was bubbling out of the Y-pipe bolts/flange area a bit, and gasket area on the reeds. I'll double check before applying RTV to the gaskets, which don't seal worth a damn. Hope that fixes it. Never had it idle up before with the choke drop fix.
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