Y80 ignition points cam issue

[ZUL8TR]

On the Y80 have any experienced the point cam cracking starting at the top where the key slot is ? The cam key slot was machined at the thinnest part of the cam so not much meat there, suppose that was a design flaw since the Yamato 102 moved the slot to the thicker part of the cam?

[Jack Stotts]

I've broken many a cam on both the Y-80 and 102. Tom Johnston (TJ) has them or at least had some.I got a 102 cam last year from him but don't have any idea about them for the Y-80. Jack

[ZUL8TR]

I've broken many a cam on both the Y-80 and 102. Tom Johnston (TJ) has them or at least had some.I got a 102 cam last year from him but don't have any idea about them for the Y-80. Jack

Thanks for the reply.
Any thoughts on why they crack at the key ? Where were your 102 cams cracking? Am I correct the 102 has the key slot in the thick part of the cam I know the Y80 does not and that's why I thought it was a design flaw with the key way in the thin area of the cam?

[Jack Stotts]

Yes, they crack at the key slot. There are cams out there that have two key slots, one for y-80 and the other for the Y-102. They crack at the key way as you have noted that that is the weakest place. The Y-80 broken cams that I have broke at the key slot. The ones that have two slots are also cracked at the y-80 slot (the weak area).

[ZUL8TR]

Yes, they crack at the key slot. There are cams out there that have two key slots, one for y-80 and the other for the Y-102. They crack at the key way as you have noted that that is the weakest place. The Y-80 broken cams that I have broke at the key slot. The ones that have two slots are also cracked at the y-80 slot (the weak area).

Thank you, guess buying cams is a regular maintenance item.

[R. C. Hawie]

Yea, the 80's are a bad design. That is why the 102 has the key way in the fat part of the cam. I found that many that cracked was because the key itself was exerting pressure on the cam. Solution one, make sure the key is flat. Solution two, rub the key on a stone and round the edges some, no sharp point.