engine break-in question
+ Reply to Thread
Results 1 to 8 of 8

Thread:
engine break-in question

  1. #1
    Member Romper Stomper's Avatar
    Join Date
    Dec 2011
    Posts
    59

    Default engine break-in question

    Well, I finally got most of the glass work and wood work done on my cvx-20 and mildly built the engine. Stock bore, 9:1 comp, mild cam, basic port on heads, alum. intake, 750 carb. My question is about the cam break-in. Can I do it on the trailer or should I do it on a stand before I even install it? Are there any straight up no-nos when it comes to running a jet dry? I am a car guy and this is my first boat, so I would appreciate any info from you folks that have been doing this for a while. Thanks in advance.

  2. Remove Advertisements
    PerformanceBoats.com
    Advertisements
     

  3. #2
    ATM
    ATM is offline
    Amerian Turbine Man
    Join Date
    Jan 2008
    Location
    Clarkston, WA.
    Posts
    88

    Default

    Quote Originally Posted by Romper Stomper View Post
    Well, I finally got most of the glass work and wood work done on my cvx-20 and mildly built the engine. Stock bore, 9:1 comp, mild cam, basic port on heads, alum. intake, 750 carb. My question is about the cam break-in. Can I do it on the trailer or should I do it on a stand before I even install it? Are there any straight up no-nos when it comes to running a jet dry? I am a car guy and this is my first boat, so I would appreciate any info from you folks that have been doing this for a while. Thanks in advance.
    I would do it on the stand. You have to be very careful doing it on the trailer because the oil can flow to the back of the pan and possibly be whipped by the crank causing aerated oil. Aerated oil does not lube cam lobes very well and you could end up with a flattened cam lobe (ask me how I know).
    Also my experience tells me not to use anything over 30wt for cam break-in, also get the engine really close so when it starts DO NOT LET IT IDLE. Better yet call the cam MFG and ask for their recommendations.
    Ron

    One less DEALER means more DISCOUNT for you

  4. #3
    Canoe Jockey Michael Thomas's Avatar
    Join Date
    Jul 2008
    Posts
    1,130

    Default

    If you could start it on a stand it would be best....it is easier to fix any issues you might have on the stand.. if you run it in the boat, leave the pump disconected
    "If you can't dazzle them with brilliance...Baffle them with bullshit"

  5. Remove Advertisements
    PerformanceBoats.com
    Advertisements
     

  6. #4
    Senior Member Futs's Avatar
    Join Date
    Dec 2007
    Location
    Orange CA, Big River
    Posts
    4,549

    Default

    What kind of cam? roller or flat tappet?

  7. #5
    Senior Member jamesblown97's Avatar
    Join Date
    Mar 2011
    Location
    st george ut
    Posts
    265

    Default

    if the motors in the boat on the trailer level the motor out with the trailer and leave the pump disconnected DO NOT RUN THE PUMP DRY. flat tappet cams and roller cams have different break in methods which kind do you have? and make sure timing is pretty close before you fire it up and try to make sure evreything is lined out motor wise before you fire it wiring water lines timing fuel ignition etc.. let us know what style cam you have and we can go from there. Pig

  8. #6
    Senior Member
    Join Date
    Jan 2012
    Location
    St. Louis, MO
    Posts
    112

    Default

    Quote Originally Posted by Romper Stomper View Post
    Well, I finally got most of the glass work and wood work done on my cvx-20 and mildly built the engine. Stock bore, 9:1 comp, mild cam, basic port on heads, alum. intake, 750 carb. My question is about the cam break-in. Can I do it on the trailer or should I do it on a stand before I even install it? Are there any straight up no-nos when it comes to running a jet dry? I am a car guy and this is my first boat, so I would appreciate any info from you folks that have been doing this for a while. Thanks in advance.
    Build yourself a hillbilly break-in stand.

    Make sure you prime the pump thoroughly with a drill before dropping the distributor in. My BBC took forever to flow oil out of the left side pushrods when I primed it. Use a high-zinc break-in additive. Make sure the carb has fuel (use a cheap electric pump like I did) before you try and fire it. Ensure that the float isn't hung up and dumping fuel straight into the manifold. Triple-check the distributor phasing and initial timing so the mother (hopefully) fires right up. Don't give it any water until it fires. Bring up to 2000-2500 rpm for 20 minutes. Check timing after it's running to ensure that it's not retarded too far so you don't burn up your exhaust valves. Shut it down abruptly (and turn the water off) if you have any issues that you need to fix, then start it up and run at 2000-2500 rpm for the rest of the break-in period. Keep a fire extinguisher nearby. Good luck!

    Oh, and post pics of your CVX-20. I always wanted one of those.....
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	100_2447.jpg 
Views:	33 
Size:	97.3 KB 
ID:	158618   Click image for larger version. 

Name:	100_2448.jpg 
Views:	39 
Size:	96.3 KB 
ID:	158619   Click image for larger version. 

Name:	100_2449.jpg 
Views:	30 
Size:	96.2 KB 
ID:	158620   Click image for larger version. 

Name:	100_2450.jpg 
Views:	40 
Size:	97.7 KB 
ID:	158621   Click image for larger version. 

Name:	100_2452.jpg 
Views:	42 
Size:	97.3 KB 
ID:	158622  

    Last edited by mpkardell; 05-01-2012 at 03:36 PM.

  9. #7
    Member Romper Stomper's Avatar
    Join Date
    Dec 2011
    Posts
    59

    Default

    Thanks for the feedback. It is a .503/.503 lift, 276/286 adv duration flat tappet cam. I have quite a bit of experience doing cam break-ins. Hell, I did one this morning on a '65 GTO with a. 060 over 400, thats what made me think about my boat. I've done probably 15 so far with no flat lobes yet (knock on wood!). I've found that Joe Gibbs BR break in oil does the job pretty well. Its a 15-50 wt. with a bunch of zinc in it. I've used it on the last five break-ins including one I had to stop in the middle because of a fuel leak and I've had no cam issues. Also, I've found that running the timing up to about 50° helps keep the exhaust cooler so it doesn't cook the ceramic off the headers. I think a am gonna make an african engine stand. If anything, just so I can see it real good when it explodes, lol. Btw, I'll post some pics when I get it cleaned up. Right now it looks like I had an epic battle with a fiberglass monster in it.

  10. #8
    Senior Member Fonz69's Avatar
    Join Date
    Jan 2008
    Location
    Frozen Tundra, WI
    Posts
    621

    Default

    just a thought but I find a dyno run helps save allot of problems, plus you wont need to worry about break-in

+ Reply to Thread

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