Results 1 to 13 of 13

Thread: Sad day...

  1. #1
    Moderator AKmud's Avatar
    Join Date
    Oct 2005
    Location
    Wasilla, Alaska, United States
    Posts
    3,185

    Unhappy Sad day...

    Well,

    Saturday started out great! We left the Parks hwy mile 128 lot around 10am and had a great trip out to Swan lake and to the Tokositna and beyond. On the way back though, I stretched it out a little too much on Swan lake and toasted a piston...

    Running at about 7800 RPM for about 30 seconds across the lake, my baby ('98 700 RMK) all the sudden bogged down to around 5000 RPM and I lost speed quickly. I nursed it along about 25 mph back to the cabin where we checked the plugs. The mag side had those tell tale little specks of molten aluminum on the plug electrode Looks like my season is over due to lack of funds for a while. My buddy with EGT's said he had been running hot temps all day so I'm not sure what the culprit was.

    The machine never seized, so I am hoping that it is only a piston and not the cylinder. Pistons are bad enough these days ($$).

    Anyway, keep posting the pics so I can dream of some awesome spring riding.....
    AKmud
    http://i78.photobucket.com/albums/j96/AKmud/213700RMK1-1.jpg


    The porcupine is a peacful animal yet God still thought it necessary to give him quills....

  2. #2
    Moderator Alaskacanoe's Avatar
    Join Date
    Apr 2006
    Location
    Sterling
    Posts
    1,450

    Cool sad day

    Yes that is a sad day...
    Lots of riding left to do this year,,,
    you best get out your wrench and get ur back spinning.
    This week I am going on a 3 day camp trip up to Upper Russian lakes, and then over to Lost lake area.
    This is my favorite time of year to sno-go..
    early this year the same thing happened to a buddy of mine, and he had his sled up and going in one day...
    Maybe talk to the Snowmobile salvage guy, or something..
    Good luck
    Max
    When you come to a fork in the trail, take it!

    Rentals for Canoes, Kayaks, Rafts, boats serving the Kenai canoe trail system and the Kenai river for over 15 years. www.alaskacanoetrips.com

  3. #3
    Member
    Join Date
    Jul 2006
    Location
    North Pole
    Posts
    52

    Default Hmm I wonder...

    Did it make a "pop" before it started bogging cause saturday mine did basically the excat same thing you are discribing except with the added pop at the beginning. I was thinking that might be what i did to mine but i think you just may have confirmed it for me. So are these engines hard to rebuild?
    Life's journey is not to arrive at the grave safely in a well preserved body but rather to skid in sideways, totally worn out, shouting "HOLY **** WHAT A RIDE!!!"

  4. #4
    Moderator AKmud's Avatar
    Join Date
    Oct 2005
    Location
    Wasilla, Alaska, United States
    Posts
    3,185

    Default

    I didn't notice a "pop", but at 80mph I wasn't really paying attention . I was getting some metal to metal sound from that side of the engine a few minutes earlier so my crank bearing my have gone out too. The rebuild usually isn't a big job (a couple of hours if you know your way around the engine) especially if you only do the top end. Problem is, when the top end goes out, shavings usually make their way to the bottom end so you might as well do the whole thing to make sure. Pistons used to be about $70 but now they are upward of $150! I guess aluminum is becoming a precious metal.

    Check the plugs and see if you have molten aluminum specks on the electrode. If you do, you better break the engine down and see what happened.
    AKmud
    http://i78.photobucket.com/albums/j96/AKmud/213700RMK1-1.jpg


    The porcupine is a peacful animal yet God still thought it necessary to give him quills....

  5. #5
    Member
    Join Date
    May 2006
    Location
    Fairbanks
    Posts
    195

    Unhappy bummer

    Same thing happend to my XLT on Teusday.
    "When everything seems to be going against you, remember that the airplane takes off against the wind, not with it."
    Henry Ford

  6. #6
    Member
    Join Date
    Jul 2006
    Location
    North Pole
    Posts
    52

    Default Yup

    Quote Originally Posted by AKmud View Post
    I didn't notice a "pop", but at 80mph I wasn't really paying attention . I was getting some metal to metal sound from that side of the engine a few minutes earlier so my crank bearing my have gone out too. The rebuild usually isn't a big job (a couple of hours if you know your way around the engine) especially if you only do the top end. Problem is, when the top end goes out, shavings usually make their way to the bottom end so you might as well do the whole thing to make sure. Pistons used to be about $70 but now they are upward of $150! I guess aluminum is becoming a precious metal.

    Check the plugs and see if you have molten aluminum specks on the electrode. If you do, you better break the engine down and see what happened.
    Well I pulled the head off the mag side cause that where the plug was with the melted aluminum was and turns out I burnt a hole straight through the piston actually looks pretty cool ill try and post a pic up tonight, But im gonna go ahead and pull the PTO head and check out that piston as well hopefully its not bad, but im thinking I may as well go ahead and replace that side too just keep things even. Heck I drink enough coke maybe I could bring in my empty cams and have them melt them down to make a piston, if it were only that easy. Thanks AKmud this should help.

    Justin
    Life's journey is not to arrive at the grave safely in a well preserved body but rather to skid in sideways, totally worn out, shouting "HOLY **** WHAT A RIDE!!!"

  7. #7
    Member
    Join Date
    Aug 2006
    Location
    Eagle River,AK
    Posts
    1,494

    Default

    I wish I could remember the number of all the Polaris's I have towed out(including a few at Mile 128)that had the same problem you guys are having.I was told by a few different people that most of those Polaris sleds are mountain sleds and set up and jetted for riding up in the MOUNTAINS.When you bring them down to the river bottems and swamps,especially with warm temps,you need to re-jet and and keep high speeds to short periods of time or your gonna blow.

  8. #8
    Member
    Join Date
    Apr 2006
    Location
    Anchorage
    Posts
    3,293

    Default

    It's cold temps you need to worry about.

    This time of year we have warm days and cold nights. That makes water in your gas tank. A little isopropyl is a good idea every now and then.

    Jet your Polaris for cold sea level and add a TempFlow. Problem solved. Most Alaskan sleds don't see enough altitude variations to make much difference if you take the temperature factor out of the equation. Mine runs the river at -30 and Summit Lake at +40 with the same jets.

  9. #9
    Moderator AKmud's Avatar
    Join Date
    Oct 2005
    Location
    Wasilla, Alaska, United States
    Posts
    3,185

    Default

    Well, I finally took the time to tear the beast apart and found out the problem. I did indeed burn a piston on the mag side right at the exhaust port. Cylinder didn't look too bad initially, we thought some muriatic acid would take care of the molten aluminum that was pasted on the cylinder walls. After closer examination though, I found a crack at the exhaust port so the cylinder is toast...

    We were having trouble figuring out what caused the burndown. I just happened to pick up the Y pipe and while examining it, I found a small (about 1" long) crack on the inside of the "Y" on the mag side. Problem figured out! The crack was letting air into the cylinder right at the exhaust port which heated it up and burnt the piston.

    Now my dilemma is whether or not to spend $1k to repair a machine that is worth $1,500 at best! If I can find some used parts I may fix it otherwise I may part it out on Craigslist....
    AKmud
    http://i78.photobucket.com/albums/j96/AKmud/213700RMK1-1.jpg


    The porcupine is a peacful animal yet God still thought it necessary to give him quills....

  10. #10
    Moderator AKmud's Avatar
    Join Date
    Oct 2005
    Location
    Wasilla, Alaska, United States
    Posts
    3,185

    Thumbs up It Lives!!!

    Well....The wife let me spend a little money and the beast is once again breathing fire! Alaska snowmachine salvage in Anchorage has really good prices on parts (about 1/2 when compared to dealer retail). I bought two new pistons (went ahead and changed the other one to keep compression more equal), a new gasket set, a used jug (Craigslist) and a friend gave me a new Y pipe. Parts total --- $420, a couple hours of labor and I had two stroke smoke filling my garage!

    Now, where did the snow go??
    AKmud
    http://i78.photobucket.com/albums/j96/AKmud/213700RMK1-1.jpg


    The porcupine is a peacful animal yet God still thought it necessary to give him quills....

  11. #11

    Default

    right on...congrats!

  12. #12
    Member fullkurl's Avatar
    Join Date
    Apr 2006
    Location
    Alaska/Idaho
    Posts
    2,162

    Default Egor....

    its ALIVE!!!!!!!!!!!!!

    Way to go, Rob.

  13. #13
    Member
    Join Date
    Jan 2007
    Location
    Southwest Alaska
    Posts
    2,145

    Default

    Quote Originally Posted by Mr. Pid View Post
    It's cold temps you need to worry about.

    This time of year we have warm days and cold nights. That makes water in your gas tank. A little isopropyl is a good idea every now and then.

    Jet your Polaris for cold sea level and add a TempFlow. Problem solved. Most Alaskan sleds don't see enough altitude variations to make much difference if you take the temperature factor out of the equation. Mine runs the river at -30 and Summit Lake at +40 with the same jets.

    What he said. I use the ATACC.

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •