Still Struggling with the XPAG Cam Sprocket Installation

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Paul Mascuch
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Joined: Mon Jan 07, 2013 11:25 am
Location: Parma, Idaho

Still Struggling with the XPAG Cam Sprocket Installation

Post by Paul Mascuch » Thu Jul 07, 2016 1:20 pm

Gentlemen -

I'm trying to install the cam sprocket onto the cam in my MGTC engine. I've installed the sprocket, then the oil slinger, then the flat washer, then the tab washer, and finally the bolt that holds it all together. Before I tighten the bolt I rotate the tab washer until the tab locks into the keyway. The sprocket is against the shoulder on the cam, and the end of the camshaft does not quite come flush with the face of the sprocket. the end of the camshaft is 1/8" to 3/16th short of the face of the sprocket.

The spec for the torque om this bolt is 50 foot-pounds. Once I get past 40 foot-pounds the flat washer starts to bend into to space between the face of the sprocket and the end of the camshaft. This caused the bolt to rotate trying to build the torque. At this point the bolt is very tight against the tab washer which causes the tab washer to rotate and tear off the tab.

Has anyone run into this problem before? How did you solve this problem?

Thank you for any help you can give me.

Paul Mascuch

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Gene Gillam
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Location: Saucier, MS

Re: Still Struggling with the XPAG Cam Sprocket Installation

Post by Gene Gillam » Sat Jul 09, 2016 11:19 am

Paul,

Either the cam sprocket is too thick or the distance from the end of the cam to the shoulder is too short. Are both the sprocket and the cam new? When the cam sprocket is all the way on against the shoulder is the cam sprocket and the crank sprocket aligned? If so, you could probably safely put a spacer at the end of the cam to take up that 1/8-3/16" difference.

Gene

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Gene Gillam
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Re: Still Struggling with the XPAG Cam Sprocket Installation

Post by Gene Gillam » Sun Jul 17, 2016 7:35 am

Update?

Paul Mascuch
Posts: 15
Joined: Mon Jan 07, 2013 11:25 am
Location: Parma, Idaho

Re: Still Struggling with the XPAG Cam Sprocket Installation

Post by Paul Mascuch » Wed Jul 20, 2016 7:07 am

Gene -

I was finally able to get the cam sprocket on and secured properly. I talked to Doug Pelton and he spoke with his engine rebuilder. The fix was a new thick washer and then using emery cloth to smooth the back of the bolt head and slightly rounding the sharp corners on the back of the bolt head. Then greesed the face of the tab washer and the back of the bolt head.

Also torqued to 43 foot-pounds instead of 50 per Doug's engine builders.recommendation.

Paul

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Gene Gillam
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Joined: Wed Jan 02, 2013 4:52 pm
Location: Saucier, MS

Re: Still Struggling with the XPAG Cam Sprocket Installation

Post by Gene Gillam » Wed Jul 20, 2016 2:58 pm

Paul,

Glad you got it solved.

Gene

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