MarineEngine.com - Your online store for all types of marine engines and boat parts.
PHONE ORDERS
Monday - Friday
9:00 AM - 5:00 PM EST
Click for TOLL-FREE Number
Online Checkout
Special $9.95 Flat Rate Shipping
(800) 209-9624 | Home | Contact | Shipping | Returns | Cart View your shopping cart.
Part Number Search
Shop by engine/drive part number.
Original & matching parts for sale.
Manuals & Accessories
Shop by description, item number
or manufacturer's model number.
Boat Repair Forum Boat Repair Forum   Boat Video Gallery Video Gallery
   
Results 1 to 12 of 12
  1. #1

    Default 1990 200 hp looper- low compre

    1990 200 hp looper- low compression on both bottom cylinders-55-60 psi. Pulled head and there is no cylinder wall damage?? Motor has beem built .30 over. Could the rings be stuck?
    Pistons clean enough to read part numbers.

  2. #2
    Join Date
    Nov 2005
    Location
    lockhart, texas, US
    Posts
    5,811

    Default "rings can and do stick....use

    "rings can and do stick....use a decarb solution,..lower cyl's can end up lower than the others..but u do have a prob.."

  3. #3
    Join Date
    Nov 2005
    Location
    lockhart, texas, US
    Posts
    5,811

    Default "what is comp on others,when w

    "what is comp on others,when was rebuild."

  4. #4

    Default Thanks for responding- others

    Thanks for responding- others are 87-90psi
    Rebuild time frame unknown- it has a rebuild "serial number tag" from PMC. I have decided to go ahead and tear it down- I am about 2/3's way there-stopped for lunch and saw your post. I will post my findings and questions as to "WHAT Now" later.

  5. #5
    Join Date
    Nov 2005
    Location
    lockhart, texas, US
    Posts
    5,811

    Default be sure and get u a FACTORY se

    be sure and get u a FACTORY servce manual...it has all the info u will need to rebuild it properly..

  6. #6
    Join Date
    Dec 2008
    Location
    Victoria, B.C., Canada
    Posts
    645

    Default The rings on the lower cylinde

    The rings on the lower cylinders are more suspect to sticking because they handle more backpressure than the cylinders higher up. Allowing carbon build up behind the rings. Proper engine height on transom will help prevent increased backpressure. If the exhaust ports on the leg are close to or under water it is mounted too low

  7. #7

    Default Thanks-I do have a factory man

    Thanks-I do have a factory manual- What size socket do I need for the rod bolts? 12 point something- manual says socket is 331638 - that helps alot. I am ready to pull pistons and do not have a matching socket.

  8. #8
    Join Date
    Nov 2005
    Location
    lockhart, texas, US
    Posts
    5,811

    Default its either a 12 pt 5/16 or 3/8

    its either a 12 pt 5/16 or 3/8.

  9. #9

    Default "5/16" X 12- I found ever

    "5/16" X 12- I found everything quite clean- however I did find the following:
    Bottom 2 pistons with low compression had ring lip on cylinder wall more pronounced than top of same cylinder and other pistons did not have this.
    The rings removed from same low compression cylinders were thinner (.020"/ 0116 vs .136)) measured ID to OD, opposite side from gap. I checked one of the higher compression pistons as a baseline and found .002-004 varition. Something is out of round-or wearing hard towards bottom of engine.
    Pistons from both higher compression and low compression cylinders all have have lower skirt scuffing- no cylinder wall damage visable and no transfer of aluminum."

  10. #10
    Join Date
    Nov 2005
    Location
    lockhart, texas, US
    Posts
    5,811

    Default r u still on the VRO--?

    r u still on the VRO--?

  11. #11

    Default No- why you ask?

    No- why you ask?

  12. #12
    Join Date
    Nov 2005
    Location
    lockhart, texas, US
    Posts
    5,811

    Default thinking u could have had a lo

    thinking u could have had a low ratio failure..most vro failures are due to not keeping the system in good shape.

Similar Threads

  1. How to free up rings
    By joefixit in forum Johnson Evinrude Outboard Archive
    Replies: 5
    Last Post: 11-22-2009, 07:54 PM
  2. Stuck piston rings
    By markkingscraft in forum Chrysler Inboard and Sterndrive Forum
    Replies: 12
    Last Post: 08-31-2009, 07:45 AM
  3. 75 hp rings
    By royce4554 in forum Honda Outboard Archive
    Replies: 0
    Last Post: 02-25-2009, 10:12 PM
  4. How to free stuck rings how to remove gas from carburator
    By car5car in forum Johnson Evinrude Outboard Archive
    Replies: 2
    Last Post: 12-19-2006, 12:34 AM
  5. Sticky rings
    By steve yager in forum Johnson Evinrude Outboard Forum
    Replies: 2
    Last Post: 10-15-2002, 10:30 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
  •