Results 1 to 5 of 5
  1. #1

    Rebuild 720 hx - Compression bad

    hi guys, my wife bought a disassembled HX 720. my mission was to rebuild it.


    I had sleeves size checked: they are ok
    I installed new pistons prox.
    cylinder head facing.
    the rotary valve is new, the clearance between the valve and the pipe is ok.
    timing valve is ok
    the squish is 2,00mm but the cylinders gasket is 0,3mm
    and compressions are 100psi wtf ???
    what's happening ?


















    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	84282500-2526730987453767-7837518495687376896-n.jpg 
Views:	70 
Size:	30.3 KB 
ID:	459121   Click image for larger version. 

Name:	0-A68-F6-FA-740-C-4470-88-F6-CB7-DDDF2-C1-EE.jpg 
Views:	7 
Size:	59.0 KB 
ID:	459122   Click image for larger version. 

Name:	85231579-498797757719044-2329636071471579136-n.jpg 
Views:	71 
Size:	26.0 KB 
ID:	459123   Click image for larger version. 

Name:	87255351-611418422755448-3196259922325012480-n.jpg 
Views:	65 
Size:	26.5 KB 
ID:	459124   Click image for larger version. 

Name:	45179-D86-1-C89-418-E-8-BA1-F64-BA1-C78-A14.jpg 
Views:	68 
Size:	76.2 KB 
ID:	459125   Click image for larger version. 

Name:	88057374-191753015388905-6309911573255159808-n.jpg 
Views:	68 
Size:	26.2 KB 
ID:	459126  

    Click image for larger version. 

Name:	26526342-3442-4-F2-A-9-F58-A53-E267-FCEA2.jpg 
Views:	8 
Size:	30.6 KB 
ID:	459127   Click image for larger version. 

Name:	E8781-D46-A7-B4-43-BB-8-DB6-53-EED9-AF964-B.jpg 
Views:	62 
Size:	92.2 KB 
ID:	459128   Click image for larger version. 

Name:	IMG-3907.jpg 
Views:	68 
Size:	50.1 KB 
ID:	459129   Click image for larger version. 

Name:	75322591-2621987514506685-6470564305270996992-n.jpg 
Views:	68 
Size:	21.2 KB 
ID:	459130  
    Last edited by Sylvius; 03-15-2020 at 02:10 PM.

  2. #2
    sleeves size


    compression rear and front

    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	74443918-557040841737584-5781582402019131392-n.jpg 
Views:	66 
Size:	21.1 KB 
ID:	459131   Click image for larger version. 

Name:	IMG-3906.jpg 
Views:	63 
Size:	64.9 KB 
ID:	459132  


  3. #3
    ncdoo's Avatar
    Join Date
    Nov 2007
    Location
    Eastern NC
    Posts
    2,166
    +1
    282
    Try a different gauge.

  4. #4
    Yes is it same !!

  5. #5
    Myself's Avatar
    Join Date
    May 2007
    Location
    North Central Arkansas
    Posts
    3,964
    +1
    307
    Are you saying the head was machined? Did they cut damage out of the squish but not recut the head surface?

Thread Information

Users Browsing this Thread

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

Similar Threads

  1. 720 compression when n what to rebuild
    By 123indyrt in forum Sea Doo Spark
    Replies: 5
    Last Post: 08-14-2016, 04:24 AM
  2. 1995 seadoo hx 720 compression
    By Lagzalot in forum 2-Stroke Performance
    Replies: 6
    Last Post: 06-14-2011, 11:01 AM
  3. 720 Stock head compression 150?
    By vshockey10 in forum 2-Stroke Performance
    Replies: 3
    Last Post: 04-28-2010, 02:46 PM
  4. 95 XP 720 Compression
    By Daveski in forum 2-Stroke Performance
    Replies: 3
    Last Post: 05-11-2009, 04:14 PM
  5. 95 xp 720 high compression?
    By amdeus in forum 2-Stroke Performance
    Replies: 3
    Last Post: 07-06-2008, 08:04 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
  •