Generator and Tach Drive Torques

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dstates
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Generator and Tach Drive Torques

Post by dstates »

I’m not seeing anything in the Continental M-O for specific torques for the generator and tach drive studs. Can anyone help me figure out what torques apply? I just replaced tach drive and generator seals and the shared gasket.

Thanks!
Doug
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N1235D - 1951 170A - SN: 20118
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GAHorn
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Re: Generator and Tach Drive Torques

Post by GAHorn »

The 100 Series Service Manual, 1962 and Prior has a torque-value chart, which is copied in the Mx LIbrary:

viewtopic.php?f=26&t=3571
'53 B-model N146YS SN:25713
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dstates
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Re: Generator and Tach Drive Torques

Post by dstates »

GAHorn wrote:The 100 Series Service Manual, 1962 and Prior has a torque-value chart, which is copied in the Mx LIbrary:

viewtopic.php?f=26&t=3571

Thanks, George. I didn't see anything about generator mounting torques in the 100 Series Service Manual. I'm specifically looking for the torques on the engine accessory case studs. I will default to the general torques in the Continental M-O if I don't find a specific torque.
N1235D - 1951 170A - SN: 20118
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n2582d
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Re: Generator and Tach Drive Torques

Post by n2582d »

SB95-3B specifies 180-220 inch pounds for the generator mounting nuts. The tach drive housing is mounted with 1/4-28 nuts. Table B-5 in the Continental M-0 manual lists general torque specs for this size nuts as 90-100 inch pounds - significantly higher than the 50-70 inch pounds listed in the 100 series Service Manual.
Gary
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dstates
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Re: Generator and Tach Drive Torques

Post by dstates »

n2582d wrote:SB95-3B specifies 180-220 inch pounds for the generator mounting nuts. The tach drive housing is mounted with 1/4-28 nuts. Table B-5 in the Continental M-0 manual lists general torque specs for this size nuts as 90-100 inch pounds - significantly higher than the 50-70 inch pounds listed in the 100 series Service Manual.
Thanks for the SB, Gary. I did end up using the general torque specs for both the 14/-28 tach drive nuts and the 5/16-24 generator nuts. As it works out the general torque for the 5/16 nuts is 180-220 in-lbs. and that matches with what the service bulletin has.

Thanks again!!
Doug
N1235D - 1951 170A - SN: 20118
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