Camshaft Thrust Plate, 1972 Cub

T

The Riot

Well-known member
I am rebuilding my 1972 Cub that I inherited from my father-in-law and am currently on the engine re-assembly. I have gotten to the camshaft and on page 1-45 of the Service Manual it says to "Check the end clearance between the camshaft front journal and the thrust plate" and it should be between .003 & .012. Mine is coming in at about .020 to .024 so I would really like to replace the Thrust Plate, but Case IH doesn't make the plate any more and the only source I can find for one is Used.
I'm very reluctant to put a used Part in a wear location.
Does anyone have any suggestions, ideas, or maybe can tell me how critical this tolerance is?

thank you,

The Riot
 
Thank you, Bob. I thought I had covered all of the bases. The google search came up with a few possibilities.

Also, I appreciate the welcome. I'm having fund trying to bring this nice Cub back to life.

The Riot
 
Thanks to all for the help!
Well I've run these traps and it seems that none of these sources have any New or NOS parts. All anybody has is used. So now I'm in a quandary, do I go back with my own used Thrust Plate (can't really see any wear but out of tolerance), or try and take a chance on some other used plates.
I guess I could have a machine shop build a new one for me, but that gets into a whole other set of variables.

Any thoughts, or any clue on how important this tolerance is?

Thanks again,

The Riot
 
Been thinking on this one. Is the gear fully seated on the cam shaft shoulder?
Any thoughts, or any clue on how important this tolerance is?
Click to expand...
Good question. The excess clearance wouldn't be a problem effecting the valve tappet action. Problem may be that the oil pump is attached to the back of and driven by the camshaft.

Brass stock in desire thickness. Use thrust plate as template. That's just a thought as I have not encountered this problem.
 
Since IH saw fit to publish specifications for the clearance, one cannot assume that it is of no importance. But most engine machine shops who offer rebuilds probably do not even read the specs enough to consider this one. And a search for the part leads one to believe that several of the search engine hits lead back to just one original listing.
So I have no answers.

http://www.batescorp.com/

At one time, they had some inventory of new parts. Prices at the upper end of the spectrum.
 
Great idea, Smokey. I was kinda thinking the same thing. I will be out for a couple of weeks before I can get back to the rebuild project, but as soon as I can give it a try I'll post the results for everyone.

Thanks a bunch !!!!!!

The Riot
 
Confession time: I never paid any attention to this plate and the clearance. But it may be that a round thrust washer of the same diameter as the cam journal that adjoins the thrust plate would be the best solution- installed on the camshaft and then the thrust plate installed. The ID of the washer needs to fit the camshaft snugly so that the washer runs true when turning.
 
I have to confess when this thread started I didn't even know what a camshaft thrust plate was. :roll: My contribution to the Cub Tug trophy was a used Cub throw out bearing. I removed the grease zerk and bolted it to what I now know as a camshaft thrust plate. Learn something new every day from this forum. :{_}:
 
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
 
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.
 
ndtheriot3030":bx7hvu1f said:
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
Click to expand...
The cam does not have bearings. The only concern would be the oil pump in my opinion. Flip it over, should be fine.
 
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.

thanks

The Riot
 
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.
 
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