Page 1 of 2 1 2 LastLast
Results 1 to 10 of 15
  1. #1
    johnsonmtz's Avatar
    Join Date
    Oct 2006
    Location
    Mt. Zion Illinois
    Posts
    1,250
    +1
    7

    780 Flame Arrestor on a 750

    So my SLT750 is just about done. I should have it fired up by Thursday and ready to hit the water this weekend. But, I've run into an interesting problem.

    When I tried to install the 780 flame arrestor I couldn't get the bolts to line up that hold the cover down to the base. I fought and fought with that thing and finally realized the problem. The 780 F/A cover is hitting the cylinders. It's width was designed for to have more clearance than the 750 intake provides

    I'm thinking about cutting notches in the cover to fit around the cylinders. Does this sound reasonable? My first thought was to just cut the cover like the Pro 785, but I like the idea of the skirt on the sides in case the I get water coming in around the seat.

    What do you guys think I should do?

    KJ


  2. #2
    seaobin's Avatar
    Join Date
    Jun 2007
    Location
    Raleigh, North Carolina, United States
    Posts
    1,573
    +1
    1
    think the 780 had reed spacers to give extra clearance

  3. #3
    seaobin's Avatar
    Join Date
    Jun 2007
    Location
    Raleigh, North Carolina, United States
    Posts
    1,573
    +1
    1
    can you mill teflon spacers to lift the FA high enough to clear the cylinder heads

  4. #4
    johnsonmtz's Avatar
    Join Date
    Oct 2006
    Location
    Mt. Zion Illinois
    Posts
    1,250
    +1
    7
    Quote Originally Posted by seaobin View Post
    think the 780 had reed spacers to give extra clearance
    Yes, there are 1/4" or 3/8" spacers on the 780 that go between the reed cage and the block. Also, I think the 780 intake is slightly longer. I also have a '96 SLT780. As soon as I realized the lid was hitting the cylinders I knew it was those differences between the two that was the problem.

    Rather than cut the OEM cover I may just go the hardware store and get a piece of diamond plate aluminum and make a cover. I really would like to have the side skirts, but that doesn't seem to be in the cards now. I suppose I could buy reed spacers and intake from a 780, but that's another expense. I have enough money tied up in the ski's right now and I really just need to get the thing on the water so I can actually enjoy it!

    KJ

  5. #5
    johnsonmtz's Avatar
    Join Date
    Oct 2006
    Location
    Mt. Zion Illinois
    Posts
    1,250
    +1
    7
    Quote Originally Posted by seaobin View Post
    can you mill teflon spacers to lift the FA high enough to clear the cylinder heads
    I don't have the tools for milling or the material. Plus, those spacers would be about 3" tall to make that happen

    Hmmm, but wait...the 38mm bore of the SBN is approximately 1 1/2" diameter. I wonder what would happen if I cut some pieces of 1 1/2" Schedule 40 PVC and used that as the spacer? I still have the OEM bolts for the intake that are much longer and may work with those spacers. I'd probably need to make some gaskets to go between the PVC and the carb so I don't get an air leak.

    I have some PVC scrap in the garage and may experiment with this tonight.

    One thing is for sure. I already have the carbs back on, so I'm not too keen on taking them off again. I would like to find some solution that just drops on so I'm riding by this weekend.

    KJ

  6. #6
    She likes the bike. But the ski gets her wet!!!! xlint89's Avatar
    Join Date
    Oct 2006
    Location
    Cleveland OH
    Posts
    17,328
    +1
    29
    Pics please......

  7. #7
    Bing-A-Ding-Ding-Ding, Brrrrrap! Brrrrrrrrrap!!! Polaris_Nut#1's Avatar
    Join Date
    Aug 2006
    Location
    Pittsfield, MA
    Posts
    3,350
    +1
    26
    780 carbs mount in the opposite direction. wonder if that is where the difference is? I say notch and ride if ya don't wanna give it the pro hair cut

  8. #8
    johnsonmtz's Avatar
    Join Date
    Oct 2006
    Location
    Mt. Zion Illinois
    Posts
    1,250
    +1
    7
    Quote Originally Posted by Polaris_Nut#1 View Post
    780 carbs mount in the opposite direction. wonder if that is where the difference is? I say notch and ride if ya don't wanna give it the pro hair cut
    Nah, the bores are centered over the intake, so carb direction wouldn't matter.

    Well, I had to make 2 mods to get the F/A to fit. First, I cut 1" long pieces of 1 1/2" Schedule 40 PVC. I put a sheet of 220 sand paper on a flat plate and sanded the ends smooth and flat. Second, I notched the F/A cover to clear the cylinders and head bolt. With those two mods everything fit very nicely and is secure.

    I wanted to take pics but the batteries in my camera are dead and we don't have any fresh ones in the house. If I get a chance to get some new ones I'll snap a shot of the mods and post them up.

    KJ

  9. #9
    She likes the bike. But the ski gets her wet!!!! xlint89's Avatar
    Join Date
    Oct 2006
    Location
    Cleveland OH
    Posts
    17,328
    +1
    29
    You know I was thinknig, just cut the skirt off.

    Ocean Pro Vortes Fa's, Prok, K&N, Tau Ceti, and PRO 785 FA's all have exposed mesh and don't really have issues with water ingestion.

    If you're getting that much water in the ski, you got bigger issues than a little hydrolock.....

  10. #10
    Bing-A-Ding-Ding-Ding, Brrrrrap! Brrrrrrrrrap!!! Polaris_Nut#1's Avatar
    Join Date
    Aug 2006
    Location
    Pittsfield, MA
    Posts
    3,350
    +1
    26
    Must be the reed spacers than

Page 1 of 2 1 2 LastLast

Thread Information

Users Browsing this Thread

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

Similar Threads

  1. R&D Plenum flame arrestor on 717 engine
    By rhyne717xp in forum 2-Stroke Performance
    Replies: 31
    Last Post: 06-12-2013, 10:00 PM
  2. Can i put flame arrestors on a DI or are the TB different
    By sea-one in forum 2-Stroke Performance
    Replies: 6
    Last Post: 01-28-2012, 09:18 AM
  3. WTB 780 flame arrestor or ocean pro
    By JAG1926 in forum Polaris Classifieds
    Replies: 9
    Last Post: 11-16-2011, 07:36 AM
  4. Replies: 2
    Last Post: 03-01-2011, 04:18 PM
  5. Put Ocean Pro Flame Arrestor on JS440 ??
    By Polaris_Nut#1 in forum Kawasaki How To & FAQs
    Replies: 0
    Last Post: 06-09-2010, 11:37 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
  •