Re: Camshaft Thrust Plate, 1972 Cub

Sat Feb 02, 2013 8:06 pm

Suppose that the cam journal experiences side wear also? That increases the clearance. A thrust plate could be made on a vertical milling machine or a lathe with the center section round and the same nominal diameter as the cam journal and the mounting ears cut down thinner so as to leave the center portion raised slightly to decrease the clearance.

Re: Camshaft Thrust Plate, 1972 Cub

Sat Feb 02, 2013 8:42 pm

ndtheriot3030 wrote:Thanks, Eugene. Yea, most of the used ones that have pictures of show considerable wear. Honestly, mine doesn't appear to have as much wear as most of the used ones I'm finding for sale.
I'm going to take a close look at reversing mine and I'm also seriously considering having a machine shop build me a new one to tolerance. I think that is fairly important to fit to recommended tolerance otherwise the camshaft could have a tendency to move back & forth and wear the journals and the bearings.

I think this should be called a "wear" plate instead of a thrust plate. The 1st journal of the Camshaft definately rubs against it and it obviously wears.

Take care,

The Riot

The cam does not have bearings. The only concern would be the oil pump in my opinion. Flip it over, should be fine.

Re: Camshaft Thrust Plate, 1972 Cub

Sat Feb 02, 2013 8:55 pm

On second thought, I am not sure you can flip it over , I think the holes may be offset

Re: Camshaft Thrust Plate, 1972 Cub

Sun Feb 03, 2013 10:55 am

I'm Traveling on a business trip, but as soon as I get back to my shop I'm going to get the "flip-job" a try and let everybody know.


The Riot

Re: Camshaft Thrust Plate, 1972 Cub

Sun Apr 07, 2013 5:15 pm

OK, I'm finally back on the Camshaft and Thrust Plate issue. I've decided since I can't find a new Thrust Plate and that the bearing journal is probably the piece that is worn, I am having a machine shop build a new TP for me. Since it appears that the journal is worn we will have a raised area on the TP to compensate and bring the tolerance back to .003 to .012 as per Cub Manual Spec. The raised area will be no larger in O.D. than the O.D. of the Journal. It's at the M. Shop now and I will let you know how it works out.

Re: Camshaft Thrust Plate, 1972 Cub

Mon Jun 10, 2013 12:47 pm

I have finally come up with what we think is a good solution on this Camshaft Wear Plate issue. After careful consideration by a reputable machine shop we decided to put in a Stainless Steel Spacer Washer to compensate for the wear and being over tolerance.

I am in the engine re-assembly process right now and will report back on the engine performance once I get it up and running.

thanks for all of the suggestions.