Engine cuts out under load what's your guess?
+ Reply to Thread
Page 1 of 3 1 2 3 LastLast
Results 1 to 14 of 29

Thread:
Engine cuts out under load what's your guess?

  1. #1
    Senior Member
    Join Date
    Jan 2008
    Location
    San Dimas
    Posts
    729

    Default Engine cuts out under load what's your guess?

    Ok... Let's do a little diagnostic test. 07 Howard Sportdeck with a 600sci. Last weekend we took the boat out and when the boat was under load and going over 4500 rpm the engine cut out intermittently. An alarm also sounded giving a three beeps then repeated. One time it cut out when I was coming out of the hole moderately aggressive. I checked the temperature, oil pressure, drive fluid etc. all looked perfect. When starting the engine it seemed a little slower to fire than normal. After it started it idled smooth and ran fine until it was under load and then had the bad miss. Aaron from Absolute Speed and Marine is picking up the boat tomorrow to take it in and have a look. What do you think is wrong?

    oil related?
    temperature related?
    drive related?
    water pressure related?
    electrical problem?
    fuel supply problem?

    The boat has been maintained well and has new plugs, impeller, all fluids changed etc recently. 50 hours on boat and motor.

  2. Remove Advertisements
    PerformanceBoats.com
    Advertisements
     

  3. #2
    Lord of the Drinks Havasu Hangin's Avatar
    Join Date
    Dec 2007
    Location
    273.36 Miles from Havasu
    Posts
    2,352

    Arrow

    I think the alarm will sound for low fuel pressure.
    "Warming the globe...16 cylinders at a time."

    Quote Originally Posted by Rexone View Post
    Perhaps I'm gay...

  4. #3
    Member
    Join Date
    Jan 2008
    Posts
    72

    Default

    The scale?

  5. Remove Advertisements
    PerformanceBoats.com
    Advertisements
     

  6. #4
    Maxwell Smartass Racey's Avatar
    Join Date
    Dec 2007
    Location
    Lake Meadski
    Posts
    353

    Default

    Possibly running out of fuel misfire was my first idea, but at first i thought you said 600sc (older carbed model) not the new injected sci. I have heard of engine wiring harness problems on quite a few of the new merc engines causing sporadic problems when the boat is underway. That's about my only guess based on initial statement. I'm sure the guys at absolute will figure it out, i've heard nothing but good things about them.
    Racey - Custom Fabrication Expert

  7. #5
    Nuclear Powered
    Join Date
    Dec 2007
    Location
    Phoenix
    Posts
    1,281

    Default

    I'm betting on the fuel.

    Water in tank.....
    Fuel strainer/filter
    Fuel pump
    Loose wire to fuel pump (including the battery cables)


    Does your battery gauge indicate a sudden loss of power when your engine looses power?

    Good luck....
    Lake Pleasant upper arm is open for 2011 season: http://www.theoutdoorwire.com/story/...512fhbhx78a4gc

    ----------------------------------------------------
    Lake levels and ramp conditions: http://www.srpwater.com/dwr/
    Buy your Lake passes here http://www.fs.fed.us/r3/tonto/tp/vendors.php
    Colorado river conditions: http://www.coloradoriverinfo.com/waterflowreports/

  8. #6
    Senior Member
    Join Date
    Apr 2008
    Location
    Santa Clarita Ca.
    Posts
    275

    Default

    How old is your fuel?

  9. #7
    It is what it is Outdrive1's Avatar
    Join Date
    Dec 2007
    Posts
    2,650

    Default

    Under load only? Knock sensor going off from bad or low octane fuel, fuel delivery problem possibly. Could also be a loose wire that has a bad contact when the motor is vibrating. Like a loose ground wire on the block, loose positive on the starter or even a loose wire at your ignition or kill switch on your dash.

    Gremlins on pcm motors can be hard to find. Be patient, it may take a few times to figure out.
    .
    Hey stalker, don't go away mad, just go away.

  10. #8
    8anned ChumpChange's Avatar
    Join Date
    Dec 2007
    Location
    Claremont, CA
    Posts
    4,154

    Default

    Relaxalot:

    I guess you have your answer to your fuel thread now.......

    http://www.performanceboats.com//showthread.php?t=3297
    Don't argue with idiots....they'll just bring you down to their level then beat you with experience!

  11. #9
    Islander Trailer Trash#23 lalhc's Avatar
    Join Date
    Dec 2007
    Location
    Lake Arrowhead & Lake Havasu City
    Posts
    1,520

    Default

    Did you fill up at Super Fuel?

  12. #10
    "BOUGHT NOT BUILT" 2FORCEFULL's Avatar
    Join Date
    Dec 2007
    Posts
    8,077

    Default

    merc had a problem with oil pressure senders , the motor has good oil pressuer but tells the ecm that it's low, puts it in gaurd mode, which is where you are now,

    one scan will tell

  13. #11
    Senior Member deckboat24's Avatar
    Join Date
    Feb 2008
    Posts
    133

    Default

    Quote Originally Posted by relaxalot View Post
    Ok... Let's do a little diagnostic test. 07 Howard Sportdeck with a 600sci. Last weekend we took the boat out and when the boat was under load and going over 4500 rpm the engine cut out intermittently. An alarm also sounded giving a three beeps then repeated. One time it cut out when I was coming out of the hole moderately aggressive. I checked the temperature, oil pressure, drive fluid etc. all looked perfect. When starting the engine it seemed a little slower to fire than normal. After it started it idled smooth and ran fine until it was under load and then had the bad miss. Aaron from Absolute Speed and Marine is picking up the boat tomorrow to take it in and have a look. What do you think is wrong?

    oil related?
    temperature related?
    drive related?
    water pressure related?
    electrical problem?
    fuel supply problem?

    The boat has been maintained well and has new plugs, impeller, all fluids changed etc recently. 50 hours on boat and motor.
    Had the same issue last year.... Water Pressure sensor was bad....

  14. #12
    Ultra26 # 1
    Guest

    Default

    Quote Originally Posted by relaxalot View Post
    Ok... Let's do a little diagnostic test. 07 Howard Sportdeck with a 600sci. Last weekend we took the boat out and when the boat was under load and going over 4500 rpm the engine cut out intermittently. An alarm also sounded giving a three beeps then repeated. One time it cut out when I was coming out of the hole moderately aggressive. I checked the temperature, oil pressure, drive fluid etc. all looked perfect. When starting the engine it seemed a little slower to fire than normal. After it started it idled smooth and ran fine until it was under load and then had the bad miss. Aaron from Absolute Speed and Marine is picking up the boat tomorrow to take it in and have a look. What do you think is wrong?

    oil related?
    temperature related?
    drive related?
    water pressure related?
    electrical problem?
    fuel supply problem?

    The boat has been maintained well and has new plugs, impeller, all fluids changed etc recently. 50 hours on boat and motor.
    Mine acted this way from a bad lanyard switch

  15. #13
    Senior Member
    Join Date
    Jan 2008
    Location
    San Dimas
    Posts
    729

    Default

    Quote Originally Posted by ChumpChange View Post
    Relaxalot:

    I guess you have your answer to your fuel thread now.......

    http://www.performanceboats.com//showthread.php?t=3297

    Aaron is picking it up today and I will let you know the diagnosis. The fuel was bought at Terribles and was new. Since this fuel thread I have had no fuel related problems. I spoke with Dustin Whipple and he said that he thinks it probably is a water pressure issue. The temperature is cool both water and oil. I am curious what the diagnostic tool will indicate. Hopefully something minor.

  16. #14
    Senior Member
    Join Date
    Jan 2008
    Location
    San Dimas
    Posts
    729

    Default

    Aaron called and said that the only thing he found so far was a sensor on the shift linkage was out of adjustment. He is taking it out for a lake test.

+ Reply to Thread
Page 1 of 3 1 2 3 LastLast

Quick Reply Quick Reply

Register Now

Please enter the name by which you would like to log-in and be known on this site.

Please enter a password for your user account. Note that passwords are case-sensitive.

Please enter a valid email address for yourself.

Please select your insurance company (Optional)

Log-in

Tags for this Thread

Digg This Thread

Posting Permissions

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

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95