Page 1 of 2 1 2 LastLast
Results 1 to 10 of 16
  1. #1
    Buck3yeRideR's Avatar
    Join Date
    Jun 2011
    Location
    Brunswick/Marblehead, OH
    Posts
    108

    Leak down test - I got a leak!

    Performed a leak down test with a set of racket balls and the $25 harbor freight hand vacuum pump. To my disappointment I could literally patch the vacuum on the gauge dissipate. The good news is that I could hear it coming from the front of the engine. The racket balls seem like a good method, but any chance air could be slipping past them? I used tons of grease to get a good seal.

    FYI on 2 of the 3 air intake ports i just sat the greasy racketball on top as I could not get them to stay in the ports. Trying to get them to stay in the ports is a major PITA especially with grease all over them.

    Now finding the leak------
    I don't think i can use the balls as they'll probably get ejected. There will most definitely be a leak at where the balls are just sitting on the ports. What can i use to block them off?

    Any ideas on a cheap local air pump with a gauge on it that I can use for this? I was thinking a handheld bike pump, but i would need to somehow adapt a schrader valve to 1/4".


  2. #2
    urugol's Avatar
    Join Date
    Nov 2009
    Location
    Sydney, Australia
    Posts
    1,231
    +1
    3
    Use soapy water, spray it around areas you suspect if there is a leak it will bubble up you can eliminate them one at a time till it holds pressure.

  3. #3
    BlueFishCrisis's Avatar
    Join Date
    Aug 2011
    Location
    Medina, Ohio, United States
    Posts
    4,988
    +1
    140
    I saw someone using rubber stoppers for the intake mani. You can get them at a sears hardware store or similar for a couple bucks each....

  4. #4
    Banned User
    Join Date
    Jun 2010
    Location
    Milwaukee WI
    Posts
    16,708
    +1
    1,324
    I made plates by tracing a gasket. I used 3/8 clear acrylic, you could also use aluminum. Bolt them on with gaskets, or I use a little RTV. Works perfect.

  5. #5
    Buck3yeRideR's Avatar
    Join Date
    Jun 2011
    Location
    Brunswick/Marblehead, OH
    Posts
    108
    great ideas guys. The block off plates sound excellent, but I think i'm just going to pick up some rubber stoppers like bluefish recommends. Less time consuming is ideal right now.

    Any ideas on a pump cheap local pump solution I can pick up? What do you use bluefish? I'd like to get out on the water asap

  6. #6
    Buck3yeRideR's Avatar
    Join Date
    Jun 2011
    Location
    Brunswick/Marblehead, OH
    Posts
    108
    I'm just praying there's no leaks at the crank seals on either of my machines........

  7. #7
    ripcuda's Avatar
    Join Date
    May 2010
    Location
    Newman Lake, WA
    Posts
    2,389
    +1
    166
    Yeah... putting the engine under vacuum works to find leaks... but you gotta listen for them. If you want to try soap bubbles... you need to put the engine under pressure so the air leaking out makes the bubbles.

    I too use raquetballs. I put one each in the exhaust ports on each cylinder... then put one each in the intake opening below where the carb sits. Now to get them to stay when I pump pressure in (using a hand tire pump on the fuel pulse port) I put a small piece of wood across the 3 exhaust balls and ratchet strap that board around the cylinders... then stuff a wadded paper towel under each carb throttle plate and sit the carbs (all racked together) on top of the intake balls and use the carb bolts to hold those balls down. Sounds funny and looks funny... but with a little play... it does work. Then I pump the engine and listen for hisses and spray some soapy water on suspect areas like around the crank seals.

    Good luck!

  8. #8
    BlueFishCrisis's Avatar
    Join Date
    Aug 2011
    Location
    Medina, Ohio, United States
    Posts
    4,988
    +1
    140
    Quote Originally Posted by Buck3yeRideR View Post
    great ideas guys. The block off plates sound excellent, but I think i'm just going to pick up some rubber stoppers like bluefish recommends. Less time consuming is ideal right now.

    Any ideas on a pump cheap local pump solution I can pick up? What do you use bluefish? I'd like to get out on the water asap
    All of your local auto stores will just have the mighty vac or eq. There is a Harbor Freight in Parma / Parma Heights Area...... Also one down by Portage Lakes....

  9. #9
    She likes the bike. But the ski gets her wet!!!! xlint89's Avatar
    Join Date
    Oct 2006
    Location
    Cleveland OH
    Posts
    17,329
    +1
    31
    Quote Originally Posted by ripcuda View Post
    Yeah... putting the engine under vacuum works to find leaks... but you gotta listen for them. If you want to try soap bubbles... you need to put the engine under pressure so the air leaking out makes the bubbles.

    I too use raquetballs. I put one each in the exhaust ports on each cylinder... then put one each in the intake opening below where the carb sits. Now to get them to stay when I pump pressure in (using a hand tire pump on the fuel pulse port) I put a small piece of wood across the 3 exhaust balls and ratchet strap that board around the cylinders... then stuff a wadded paper towel under each carb throttle plate and sit the carbs (all racked together) on top of the intake balls and use the carb bolts to hold those balls down. Sounds funny and looks funny... but with a little play... it does work. Then I pump the engine and listen for hisses and spray some soapy water on suspect areas like around the crank seals.

    Good luck!
    That's what I do too. Use the carbs to hold the pieces down, and duct tape to hold the exh manifold one. (sometimes it does slip off though and you get a nice "POP"


    Buckeye, load up your engine and come on bye. We'll find that leak....

  10. #10
    Buck3yeRideR's Avatar
    Join Date
    Jun 2011
    Location
    Brunswick/Marblehead, OH
    Posts
    108
    Quote Originally Posted by BlueFishCrisis View Post
    All of your local auto stores will just have the mighty vac or eq. There is a Harbor Freight in Parma / Parma Heights Area...... Also one down by Portage Lakes....
    It doesn't seem to me like there's and easy hand held pressure pump solution available. I visit HF in Parma quite often and I picked up the hand vacuum pump there. I found a way to attach a schrader to barb though so I'm planning on piecing something together.
    Quote Originally Posted by xlint89 View Post
    That's what I do too. Use the carbs to hold the pieces down, and duct tape to hold the exh manifold one. (sometimes it does slip off though and you get a nice "POP"


    Buckeye, load up your engine and come on bye. We'll find that leak....
    Wish I could but it's in the ski and I don't want to take the endeavor of removing it when everythings almost done (hopefully). If I have a crank seal leak I may just run it, after all this is the ski I ran all last summer with no problems.

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. Leak Down Test
    By FLjoyrider in forum Polaris Open Discussion
    Replies: 7
    Last Post: 04-10-2008, 06:56 PM
  2. Pressure / leak down test
    By bainer1290 in forum Yamaha PWC Performance (2-stroke)
    Replies: 2
    Last Post: 12-22-2007, 01:12 PM
  3. Leak Down test
    By texoma in forum Polaris How To & FAQs
    Replies: 1
    Last Post: 06-03-2007, 07:19 PM
  4. leak down test question:
    By Pale Rider in forum Sea Doo Open Discussion
    Replies: 13
    Last Post: 11-23-2006, 09:56 AM
  5. Leak down test
    By Red Devil in forum 4-Tec Performance
    Replies: 35
    Last Post: 10-11-2006, 07:48 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
  •