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  1. #1

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    4Tec Head Bolt/Rocker Bolt Torque Question

    So, I know the manual states the torque specs for the head bolts and rocker bolts. However, since there is an angular torque involved with getting these bolts right, does anyone know what torque values these bolts should end up torqued to after its said and done.

    I am wanting to check each bolt to make sure its at said amount.

    EX. setting a torque wrench to said amount and making sure it breaks and bolt doesn't move.


  2. #2
    Moderator Snoman's Avatar
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    With the torque spec of the head bolts in the manual, it has been found that with the higher boost levels that OEM spec is to low as people were starting to blow head gaskets...92 ft lbs seems to be were you want your head bolts to be torqued to..as far as your rocker bolts? OEM torque spec is all you need..

  3. #3
    Can the head bolts be re used and re torched with no issues of them stretching or braking?

  4. #4
    Moderator Snoman's Avatar
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    I do not recommend it as your head bolts are stetch bolts..Tthey are not recommended to be used again

  5. #5
    Quote Originally Posted by Snoman View Post
    With the torque spec of the head bolts in the manual, it has been found that with the higher boost levels that OEM spec is to low as people were starting to blow head gaskets...92 ft lbs seems to be were you want your head bolts to be torqued to..as far as your rocker bolts? OEM torque spec is all you need..
    Sorry, but you are wrong Snoman. Please do not confuse ARP stud torque values with the OE stretch bolts. Stay consistent with one topic at a time....LOL

  6. #6
    Quote Originally Posted by tacomaguy00 View Post
    So, I know the manual states the torque specs for the head bolts and rocker bolts. However, since there is an angular torque involved with getting these bolts right, does anyone know what torque values these bolts should end up torqued to after its said and done.

    I am wanting to check each bolt to make sure its at said amount.

    EX. setting a torque wrench to said amount and making sure it breaks and bolt doesn't move.
    There isn't a torque value for stretch bolts. You need to get them into the stretch zone, at which point they give the maximum clamping pressure. Stretch bolts are used to overcome the two key limitations of traditional fasteners, which are 1) a poor correlation between applied torque to clamping pressure, and 2) change in clamping pressure over heat cycling. (which is why you have to retorque ARP studs all the time..)

    OE stretch bolts don't cut it for high boost, because you cannot apply more torque to get higher clamping pressure.

    You can reuse the head bolts just fine. They are designed for multiple stretch applications. 4TEC manuals up to 2005 say you can reuse them. Sea Doo changed their recommendation in 2006 because of poor training at the dealer level.

    When you use stretch bolts, it is better to judge them by feel. I have seen both used and brand new head bolts yield at a lower than normal clamping pressure. The point is that all the bolts should have a yield point that is consistent, if one or more yield at a lower torque, throw it away. Vern wrote up about this phenomena a couple years ago, I just looked for the thread but couldn't find it.

  7. #7
    dnielsen's Avatar
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    Sorry Sea Dood but you are WRONG on the ARP studs, these DO NOT need re-torqued "all the time". Simply recheck after a couple heat cycles and that's it.

    However you are correct on the rest of your post, many guys reuse the bolts without issue but are careful to pay attention to feel as they are reaching the maximum clamp angle. If it doesn't feel right throw it away! I also remember the write up........

  8. #8
    Moderator Snoman's Avatar
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    Quote Originally Posted by Sea Dood View Post
    Quote Originally Posted by Snoman View Post
    With the torque spec of the head bolts in the manual, it has been found that with the higher boost levels that OEM spec is to low as people were starting to blow head gaskets...92 ft lbs seems to be were you want your head bolts to be torqued to..as far as your rocker bolts? OEM torque spec is all you need..
    Sorry, but you are wrong Snoman. Please do not confuse ARP stud torque values with the OE stretch bolts. Stay consistent with one topic at a time....LOL
    You are right,after re-reading my post i am sorry for the mis-information...Although I will say from the other side of the ball that back when the bigger Scers came out guys started experiancing blown head gaskets,Even Jerry..Couldnt figure out why..Then Jerry happened to check his head bolts and they were not even tight,they stretched to the point were it was letting the head gasket not seal...So Jerry did in fact take a torque wrench to the bolts and found they were at something like 75-77 ft lbs of torque on them..he then bumped it up to 85 or so and his gasket sealed back up...I remember this cause this was back when SHibby was a moderator and him and Jerry discussed this in a thread..I will try to see if i can find it and post it..

  9. #9
    shrabber's Avatar
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    You can reuse the head bolts just fine. They are designed for multiple stretch applications. 4TEC manuals up to 2005 say you can reuse them. Sea Doo changed their recommendation in 2006 because of poor training at the dealer level.


    You Kidding Me right There stretch to Yield Never reuse stretch to Yield Bolts Never.

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  11. #10
    Measure them, if they're the same as new re-use them. Like others have said, when you've done enough of them you get the feel for it

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