Page 1 of 3 1 2 3 LastLast
Results 1 to 10 of 30
  1. #1

    Join Date
    May 2014
    Location
    capac MI
    Posts
    29

    parts swapping 94/95 slt 750

    Hi all!

    New to the site, and fairly new to pwc's. looking for some advice on my slt 750s'. there is some GREAT info on this site, and its helped me alot already, so thanks for that everyone!!! Im an ASE cert. mechanic so feel free to get technical, and i apologize for my bad spelling ahead of time!


    So my situation is this, at the end of last fall i bought a beater 95 slt750 from a local repair shop for $300 they had used it for towing broken jetskis and as a spare ski, long story short after 15min of riding this year (just long enough to get out into lake Huron) it melted a piston, mostly my fault for not fixing the common issues. a few days latter a 94 slt750 popped up on CL with a broken steering nozzle but a good motor, so i picked it up for $250 with a plan to use one for parts.

    Now i have a few options for fixing them and im curious what you guys recommend.

    The 94 appears to be mostly original, its had engine work done as the heads are not numbered correctly, but it starts and runs decent. compression is acceptable, 123,123,119 (mag,cen,pto) but i can hear a bad bearing in the pump. its sat for probably a year maybe a little more. and i havent leaktested it yet.

    The 95 has had a bit of work done, removed water separator, bypassed fuel selector, converted to premix, stuff like that. the pump is good, no cavitation, and no noise from the bearings.

    What i had in mind was putting the 94's motor into the 95, but the more i look into it im thinking of swapping the good pump into the 94 and using that hull. obviously i"m going to get the triple outlet pump, replace fuel lines, replace oil lines, bypass the fuel selector, and possibly bypass the water separator. And of course clean the gas tank, carbs, new plugs, and get new filters for whichever ski i use. Both hulls are in similar condition so its pretty much down to what is less work, and since i would have to remove the pumps to swap motors anyways it sounds smarter to just swap pumps. I could swap a piston/ cylinder from the good engine to the bad one but that's kind of silly...

    also if someone could answer some questions, not very important just curiosity.
    #1, how often do center seals go bad on these engines? the center cylinder isn't getting enough gas on the blown engine since the pto piston melted.

    #2 are there any major differences from the 94 to the 95 that i should know about?

    here is a pic of the 94

    Click image for larger version. 

Name:	CAM00287.jpg 
Views:	56 
Size:	82.2 KB 
ID:	329667

    and one of the 95

    Click image for larger version. 

Name:	CAM00288.jpg 
Views:	44 
Size:	141.2 KB 
ID:	329668


    and here is a pick of my hilarious wave jammer, less than 50 hrs, in mint condition, picked it up for $350 a year ago! some quality, unstable entertainment

    Click image for larger version. 

Name:	CAM00286.jpg 
Views:	44 
Size:	52.9 KB 
ID:	329670
    Last edited by ub3r l33t dud3; 05-18-2014 at 11:12 AM.


  2. #2
    BlueFishCrisis's Avatar
    Join Date
    Aug 2011
    Location
    Medina, Ohio, United States
    Posts
    4,988
    +1
    140
    No major differences between the 94 and 95. The plan to swap your 95 pump into the 94 makes sense.

    Do not bypass the fuel selector and water separator. The selector can be easily rebuilt to prevent air from entering the system. Removing it can allow the pressure to build in the fuel system, flooding the carbs/engine as the pressure pushes past the needle valves. This could also cause leaking into the hull resulting in the potential for fire.

    If your separator includes a small mesh filter, this can take place of the other fuel filters in the system. If not, you can find a used one for around $20 - 30.

    The crankcase is not sealed internally between cylinders. The only seals are on the MAG and PTO ends. If the PTO piston melted down, it is likely either due to the fuel pump, carb needs rebuilt, or the crank seals are bad. All three should be addressed to keep the ski reliable. Rebuild the carbs with Genuine Mikuni rebuild kits including needle valve replacement.

    The return line has a small brass restrictor an inch or two after the carb between the carbs and the fuel tank. When you replace the fuel lines, be sure to locate and reinstall this restrictor.

    Ensure your venting is also working properly. There are two independent check valves, one to allow vapor out, and air in, to the tank....
    Last edited by K447; 05-18-2014 at 07:15 PM.

  3. #3

    Join Date
    May 2014
    Location
    capac MI
    Posts
    29
    Quote Originally Posted by BlueFishCrisis View Post
    The crankcase is not sealed internally between cylinders. The only seals are on the MAG and PTO ends.
    i was thinking that was the case, i couldnt find any info on them or replacements. im curious why the center started starving for fuel when the pto burnt through.

    iv been messing around with them today and noticed that i already have the triple outlet pump on the 95, so its looking like dirty carbs are the suspect for the burnt piston. another thing i the 95 is missing is the 90* rubber boot that goes on the air box, i dont know how these specific engines respond to that but i know that if you did that on a snowmobile or any 2 stroke atv you will run lean since you have changed the volumetric efficiency of the intake.


    another question that i cant seam to find an answer for. the 95 has 3 nozzles, one per intake, in the intake runners of the airbox, right above the carbs. they each have a hose that runs under the engine, but the 94 has none of that. any ideas?

    so far im not very impressed with these, it seems like you have to do atleast $200 or more worth of repairs before you can even ride them
    Last edited by ub3r l33t dud3; 05-18-2014 at 05:09 PM.

  4. #4
    BlueFishCrisis's Avatar
    Join Date
    Aug 2011
    Location
    Medina, Ohio, United States
    Posts
    4,988
    +1
    140
    Quote Originally Posted by ub3r l33t dud3 View Post
    i was thinking that was the case, i couldnt find any info on them or replacements. im curious why the center started starving for fuel when the pto burnt through.
    If the PTO crank seal is blown, the air leak could likely cause a holed PTO and lean out the CEN, as they are technically not sealed from one another.

    Quote Originally Posted by ub3r l33t dud3 View Post
    another thing i the 95 is missing is the 90* rubber boot that goes on the air box, i dont know how these specific engines respond to that but i know that if you did that on a snowmobile or any 2 stroke atv you will run lean since you have changed the volumetric efficiency of the intake.
    You may need to adjust setting, but the change should be minimal for simply losing that boot.


    Quote Originally Posted by ub3r l33t dud3 View Post
    another question that i cant seam to find an answer for. the 95 has 3 nozzles, one per intake, in the intake runners of the airbox, right above the carbs. they each have a hose that runs under the engine, but the 94 has none of that. any ideas?
    These are the oil injection lines. The locations of these were changed over the various years. IF the other ski is premix, the lines would have been removed. They may also be on spacers between the carbs and FA, or in the intake manifold itself. The later 780 models have the injection connections directly on the carb bodies.

    Quote Originally Posted by ub3r l33t dud3 View Post
    so far im not very impressed with these, it seems like you have to do atleast $200 or more worth of repairs before you can even ride them
    You didn't expect to perform any corrective and/or routine maintenance on a 20 year old $250/$300 ski? I would expect to spend around $500-800 to get it up to full reliable top running condition...

  5. #5

    Join Date
    May 2014
    Location
    capac MI
    Posts
    29
    Quote Originally Posted by BlueFishCrisis View Post
    If the PTO crank seal is blown, the air leak could likely cause a holed PTO and lean out the CEN, as they are technically not sealed from one another.
    I was thinking this after the not having center seals comment finally sank into my head.


    Quote Originally Posted by BlueFishCrisis View Post
    These are the oil injection lines. The locations of these were changed over the various years. IF the other ski is premix, the lines would have been removed. They may also be on spacers between the carbs and FA, or in the intake manifold itself. The later 780 models have the injection connections directly on the carb bodies.
    After re-examining them that is what i found out. the 94 has them on what appears to be the intake, next to the impulse line ports. the guy at the repair shop said that it was premix but didnt seem confident on the oil injection being deleted, he kept changing his story, but he said he wasent the main mechanic, more of a sales man... so who knows lol.

    Quote Originally Posted by BlueFishCrisis View Post
    You didn't expect to perform any corrective and/or routine maintenance on a 20 year old $250/$300 ski? I would expect to spend around $500-800 to get it up to full reliable top running condition...
    Im not saying that at all,nor was i talking about my SLTs' specifically.what i meant was no matter how much you spent on one of these, you are most likely looking at a full overhaul of the fuel system, unless the PO did it. Im sorry if you took offense to that, that was not my intention at all, i was just making an observation (il admit i was a-bit upset about the situation still) that these seam to be somewhat problematic. however i dont have much experiance with many other skis.
    Last edited by ub3r l33t dud3; 05-18-2014 at 08:07 PM.

  6. #6

    Join Date
    May 2014
    Location
    capac MI
    Posts
    29
    upon further examination of the skis this is what i have found;

    on the 94: all the fuel hoses have been replaced, aswell as re-routed for even fuel distribution, the auto cock has not been removed, yet, and the impeller/wear ring tolerances seam pretty loose (switching pumps anyways so no biggy). still has restrictor, found the bilge hoses that where MIA, and the oil injection is functioning,and i dont see much piston wash on any of the cylinders (not surprising)

    on the 95: triple outlet fuel pump, fuel hookups on the carbs are different, with the return line exiting out the front (so it dosent trap air from what iv been reading) and still has the restrictor.


    so far i THINK i have everything under control, except i dont know how one changes the oil lines with the motor in the ski but i havent looked that up yet. im almost to the point of starting to swap all the good parts onto the 94, so we'll see how that goes.

    now my biggest problem is that spell check thinks restrictor is spelled wrong ... is it????

  7. #7
    BlueFishCrisis's Avatar
    Join Date
    Aug 2011
    Location
    Medina, Ohio, United States
    Posts
    4,988
    +1
    140
    Quote Originally Posted by ub3r l33t dud3 View Post
    now my biggest problem is that spell check thinks restrictor is spelled wrong ... is it????
    Nah..... You'll get used to it....

    The oil pump is mounted low on the block with a gear that rides on the crank. The clamps holding the lines on are simply spring loaded. Get yourself a small mirror to take a look and familiarize yourself with the layout.....

    Either the oil pump is pumping oil or not. Some do not remove it when switching to premix and you technically don't need to.....

  8. #8

    Join Date
    May 2014
    Location
    capac MI
    Posts
    29
    hmm ok, in snowmobiles if you dont remove the pump it runs dry and grenades into the engine. but im not using that motor anyway so no problem.

    and ok il give that a shot once i get the oil hose.

    thanks for your help, i appreciate it!

  9. #9
    BlueFishCrisis's Avatar
    Join Date
    Aug 2011
    Location
    Medina, Ohio, United States
    Posts
    4,988
    +1
    140
    Quote Originally Posted by ub3r l33t dud3 View Post
    hmm ok, in snowmobiles if you dont remove the pump it runs dry and grenades into the engine. but im not using that motor anyway so no problem.

    and ok il give that a shot once i get the oil hose.

    thanks for your help, i appreciate it!
    I'd definitely remove the pump for the same reason, and install the proper block off plate - if you are switching to premix that is.....

  10. #10

    Join Date
    May 2014
    Location
    capac MI
    Posts
    29
    got off work early today so i pulled the pump on the 94, found that the pump bearing is good, so im assuming its the carrier bearing, which has a broken grease zerk. going to look into swapping the bearing from the 95, however i know the bearing seal is bad on the 95, but il just keep it greased up good. below are some pictures of the impeller and pump, the impeller has a few dings in it, but a rock has bent the trailing edge of one of the impeller fins, and took a chunk out of a vane in the pump, (that's called a stator correct?). so im going to examine the 95's pump and see what shape thats in, other than that everything looks in good shape, the drive shaft is not worn down in any spots, and the splines on the end are 100% perfect, no wear at all.

    so do these have different impellers? or did all the 750s come with the same one? im guess im putting the better of the two in anyways just curious if they are different.



    Click image for larger version. 

Name:	CAM00293.jpg 
Views:	27 
Size:	69.7 KB 
ID:	329872

    Click image for larger version. 

Name:	CAM00292.jpg 
Views:	30 
Size:	98.8 KB 
ID:	329873

    Click image for larger version. 

Name:	CAM00294.jpg 
Views:	32 
Size:	81.3 KB 
ID:	329874

    Click image for larger version. 

Name:	CAM00295.jpg 
Views:	34 
Size:	100.7 KB 
ID:	329875
    Last edited by ub3r l33t dud3; 05-20-2014 at 01:46 PM.

Page 1 of 3 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. FS - Parts 95 SLT 750 Part Out
    By jonjonwells in forum Polaris Classifieds
    Replies: 9
    Last Post: 07-14-2013, 03:34 PM
  2. WTB - Parts (2) CDI's for 94/95 SLT 750 and an MFD for a 99 x-45
    By mccann316 in forum Polaris Classifieds
    Replies: 3
    Last Post: 05-17-2012, 07:00 AM
  3. WTB Polaris 94/95 SLT 750 Steering Cable in GREAT CONDITION
    By mkulczyckyj in forum Polaris Classifieds
    Replies: 3
    Last Post: 05-18-2010, 08:00 AM
  4. FS 95 slt 750 parts
    By dirtdude35 in forum Polaris Classifieds
    Replies: 2
    Last Post: 05-14-2010, 05:13 PM
  5. Need parts for 95 SLT 750 Polaris
    By ikuspalatinus in forum Polaris Classifieds
    Replies: 3
    Last Post: 05-08-2008, 10:29 PM

Posting Permissions

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