Cam Thrust bearing too tight, I've tried 3 sets Options

[Al Meredith]

The last couple of TY 4s I.ve built all have had a problem with the thrust cam Bearing. The side with the shoulders is always too tight. The cam will not spin freely . The other side , without the shoulders spins free. I 've tried three different brands and they have the same problem . The used ones have the gray finish warn but they spin fine. AL

[rfinegan]

....don't forget the "tap a tap a" to seat the bearings after they get a light sanding
no video
1) lightly side one side of the cam thrust and try to fit in case half
2) rotate cam for bind or cam/ bearing lifting out of case
3) little sand opposite side and check fit
4) rotate come and check for bind in case 1/2 or cam /bearing lift out of case
5) once the cam is spinning and no longer lifting, use a brass or aluminum punch or wooden block and give the front of the cam 2-3 light taps to to seat the bearing.
6) repeat the 2-3 taps at the base end of the cam
7) measurements or about 0.002 is the goals for endshake of the camshaft
8) repeat above till the desired endplay in this 1/2 is achieve
9) repeat above on the other case 1/2 if using a double thrust ( a quick measure meant of the "good" thrust bearing will speed things up)
10) when assembling the case 1/2s together a final check of the end pay can be performed


If I fit another set, i would fit the back side of the thrust bearing furthest from the gear, as the face closest to the gear will get the force from the angle cut gear
I hope this helps