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CVO Technical => Twin Cam => Topic started by: pewterbike1 on February 14, 2020, 08:33:25 AM
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Hey. I read and seen mechanics torquing then loosening head bolts then re-torquing again on a twin cam but most only torque once.why the 2 different ways and which should one use. thanks.
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Why bother? Twin cams seal and last when torqued per the manufacturers recommendations.
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I really like the O-Ring cylinder base gasket on the earlier TC motor I assume the 110 have the same?
Old EVO motors has issues especially on front left of cylinder base paper gaskets
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I recently did the 117ci upgrade torqued according to the instructions which said to use manual specs. Ended up with cylinder base seepage. Kit came with cometic head gasket had to retorque bolts according to cometic specs. I believe Harley instructions are for stock gaskets.
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That’s a correct statement Stuart, I found that out myself too....
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The CVO 110 requires a quad ring, 11907, at the base besides the green (OEM are green) orings. If using Cometic head gaskets then follow their torqueing procedure. 42# is the final pull. They do not require retorqueing. 103 and 96" twin cams use a standard oring 11256, same recommendations. If using OEM composite head gaskets follow the factories degree tightening method and again no retorquing is required.
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What I meant by retorqueing is I tightened to 42 lbs without loosening head bolts. Too early to see if it works. If not I will have to do it all over again with all new gaskets.
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On a twin cam if they are leaking, base or head there is something wrong. A few examples, the heads were not torqued accurately, one or more of the surfaces were not straight and true, the studs are pulling, the orings on the dowels at the base are doubled up (oh my is this a bad one), proper lubrication of the bolts, and more.
People assume their torque wrenches are accurate. They are not always and even comparing a click stop to a digital will surprise you the stated allowables, + 4% VS +1.5%, if memory serves me right. So when is the last time your torque wrench was calibrated? If it was is the tool of high enough quality to stay put for a while? Personally I have several torque wrenches and use different tools according to the application. I torque heads and torque plates with a CDI digital that was calibrated at the factory last month.
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I used a snap on 3/8 drive torque wrench. I also compared to a clicker type both very very close.
Before you say it I know 2 wrongs don't make a right.