Page 1 of 5 1 2 3 ... LastLast
Results 1 to 10 of 44
  1. #1

    Join Date
    Mar 2013
    Posts
    230

    1996 Polaris sltx, QUESTION

    I found a 1996 polaris sltx a guy wants to sell. He says when he gets it to plane off, it loses power. He thinks it is carbs need to rebuild. He hasnt done compression test. Does this sound right before I waste a trip to look at it. I can handle carbs, but not engine problems. Thanks Jason


  2. #2
    David Drkvampire2001's Avatar
    Join Date
    Jul 2011
    Location
    Edgerton, Wisconsin, United States
    Posts
    2,857
    +1
    30
    Jason, depends how much he is asking, is a trailer included?

  3. #3
    Click avatar for tech links/info, donation request K447's Avatar
    Join Date
    Jul 2007
    Location
    near Toronto, Canada
    Posts
    36,572
    +1
    1,272
    It would be guessing to try to say what is wrong. Just what might be wrong.

    Might be the usual carbs plus fuel system cleaning, new hoses etc. Or it could be that AND something else*.

    No compression test? You need to do your own then.

    Bring a strong battery with you. Often the seller's battery is marginal, even if it starts the engine.

    Something else*

    Electrical/stator/CDI
    Wrong spark plugs
    Old/bad fuel. Contaminated fuel.
    Damaged intake reeds
    Cylinder compression
    Etc...

  4. #4

    Join Date
    Mar 2013
    Posts
    230
    The guy checked the compression. It was 138,138, and 121. Does that sound ok????

  5. #5
    Click avatar for tech links/info, donation request K447's Avatar
    Join Date
    Jul 2007
    Location
    near Toronto, Canada
    Posts
    36,572
    +1
    1,272
    Quote Originally Posted by jasonmd13 View Post
    The guy checked the compression. It was 138,138, and 121. Does that sound ok????
    Not really.

    Normally you want all three cylinders to be within 5% of each other. That 121 reading is 14% different from 138.

    That said, many people do not know how to measure compression properly.

    The battery must be strong, this is not optional.

    The throttle must be held wide open, with all spark plugs removed.

    Each cylinder should be checked twice. I prefer to check each cylinder once, then go back and check each one again. The two readings for each cylinder should match fairly closely. If they don't then check again.

    If the battery is getting weak during the tests then the numbers will shrink, which is why the battery has to be healthy.

    Do not add oil to the cylinders until you are sure you have accurate 'dry' numbers. A small dribble of oil will boost compression readings if the piston rings and/or cylinder walls are worn and not sealing well. If adding oil boosts the readings, all that really tells you is that the oil is affecting the readings. If the dry readings are not good, then there often is no point to testing with oil. You already know the engine top has to be opened up to inspect or repair the problem.

    If the engine was winterized with fogging oil or any oil was added through the spark plug holes then the engine may need to be run until the fogging oil is burned off, so that the compression readings can be more accurate.

  6. #6

    Join Date
    Mar 2013
    Posts
    230
    He was told that because the jet ski bogs down, the carb might be stopped up and that would cause the compression to be lower on that cylinder. But supposely, it idles good.

    I am no scared of carb work but I cant fix piston or cylinder problems. If these reading are correct, Should i stay away from it???


    Quote Originally Posted by K447 View Post
    Quote Originally Posted by jasonmd13 View Post
    The guy checked the compression. It was 138,138, and 121. Does that sound ok????
    Not really.

    Normally you want all three cylinders to be within 5% of each other. That 121 reading is 14% different from 138.

    That said, many people do not know how to measure compression properly.

    The battery must be strong, this is not optional.

    The throttle must be held wide open, with all spark plugs removed.

    Each cylinder should be checked twice. I prefer to check each cylinder once, then go back and check each one again. The two readings for each cylinder should match fairly closely. If they don't then check again.

    If the battery is getting weak during the tests then the numbers will shrink, which is why the battery has to be healthy.

    Do not add oil to the cylinders until you are sure you have accurate 'dry' numbers. A small dribble of oil will boost compression readings if the piston rings and/or cylinder walls are worn and not sealing well. If adding oil boosts the readings, all that really tells you is that the oil is affecting the readings. If the dry readings are not good, then there often is no point to testing with oil. You already know the engine top has to be opened up to inspect or repair the problem.

    If the engine was winterized with fogging oil or any oil was added through the spark plug holes then the engine may need to be run until the fogging oil is burned off, so that the compression readings can be more accurate.

  7. #7
    David Drkvampire2001's Avatar
    Join Date
    Jul 2011
    Location
    Edgerton, Wisconsin, United States
    Posts
    2,857
    +1
    30
    Quote Originally Posted by jasonmd13 View Post
    He was told that because the jet ski bogs down, the carb might be stopped up and that would cause the compression to be lower on that cylinder. But supposely, it idles good.

    I am no scared of carb work but I cant fix piston or cylinder problems. If these reading are correct, Should i stay away from it???


    Quote Originally Posted by K447 View Post
    Quote Originally Posted by jasonmd13 View Post
    The guy checked the compression. It was 138,138, and 121. Does that sound ok????
    Not really.

    Normally you want all three cylinders to be within 5% of each other. That 121 reading is 14% different from 138.

    That said, many people do not know how to measure compression properly.

    The battery must be strong, this is not optional.

    The throttle must be held wide open, with all spark plugs removed.

    Each cylinder should be checked twice. I prefer to check each cylinder once, then go back and check each one again. The two readings for each cylinder should match fairly closely. If they don't then check again.

    If the battery is getting weak during the tests then the numbers will shrink, which is why the battery has to be healthy.

    Do not add oil to the cylinders until you are sure you have accurate 'dry' numbers. A small dribble of oil will boost compression readings if the piston rings and/or cylinder walls are worn and not sealing well. If adding oil boosts the readings, all that really tells you is that the oil is affecting the readings. If the dry readings are not good, then there often is no point to testing with oil. You already know the engine top has to be opened up to inspect or repair the problem.

    If the engine was winterized with fogging oil or any oil was added through the spark plug holes then the engine may need to be run until the fogging oil is burned off, so that the compression readings can be more accurate.
    Its simple to replace pistons and cylinders using zigler. For 850 bucks with a double trailer you can't go wrong.

  8. #8
    Tony's Avatar
    Join Date
    May 2007
    Location
    North Carolina
    Posts
    1,760
    +1
    38
    Quote Originally Posted by K447 View Post
    Quote Originally Posted by jasonmd13 View Post
    The guy checked the compression. It was 138,138, and 121. Does that sound ok????
    Not really.

    Normally you want all three cylinders to be within 5% of each other. That 121 reading is 14% different from 138.
    5% of average or 10% highest to lowest.

  9. #9
    Tony's Avatar
    Join Date
    May 2007
    Location
    North Carolina
    Posts
    1,760
    +1
    38
    Quote Originally Posted by jasonmd13 View Post
    am no scared of carb work but I cant fix piston or cylinder problems. If these reading are correct, Should i stay away from it???
    Replacing a piston or cylinder is as easy or easier than removing and rebuilding a carb rack. It may seem daunting but if you look around the site you will find plenty of post with pictures on cylinder/piston replacement. The "projects" section is a good place to start.

    The cylinder with 121# may be a false reading or it may just need to be honed and a new set of rings installed. I doubt this is the main issue with the ski and I certainly wouldn't let it be a deal breaker depending on other factors with the ski.

  10. #10
    Click avatar for tech links/info, donation request K447's Avatar
    Join Date
    Jul 2007
    Location
    near Toronto, Canada
    Posts
    36,572
    +1
    1,272
    Quote Originally Posted by jasonmd13 View Post
    He was told that because the jet ski bogs down, the carb might be stopped up and that would cause the compression to be lower on that cylinder...

    I am no scared of carb work but I can't fix piston or cylinder problems...]
    Carb problems can only affect compression by allowing piston/cylinder damage due to lean burn (insufficient fuel delivery from a given carb can cause that piston to run too hot and degrades the metal).

    If the compression test was done with the throttle closed then the readings are not useful for your purposes.

    Not sure why you are afraid of cylinder and piston top end work but OK with carburetor work. These engines are fairly straightforward to work on, and there is certainly lots of info and help around here.

Page 1 of 5 1 2 3 ... LastLast

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. 1996 Polaris SLTX No Spark troubleshooting question
    By aaron85207arizona in forum Polaris Open Discussion
    Replies: 4
    Last Post: 06-02-2009, 09:44 AM
  2. 1996 Polaris SLTX Stator Removal
    By 1996SLTX in forum Polaris Open Discussion
    Replies: 12
    Last Post: 09-16-2008, 04:21 PM
  3. 1996 Polaris SLTX..HELP!
    By Jeff Bell in forum Polaris Open Discussion
    Replies: 12
    Last Post: 09-11-2008, 10:58 AM
  4. 1996 Polaris SLX750. Questions??
    By shady0667 in forum Polaris Open Discussion
    Replies: 2
    Last Post: 05-31-2007, 02:59 PM
  5. 1996 Polaris SLTX
    By 1996SLTX in forum Polaris Open Discussion
    Replies: 14
    Last Post: 05-25-2007, 10:00 AM

Posting Permissions

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