Hi all,
Edit: sorry, I can't figure out how to embed pictures with the new forum software. Here's a link to all pictures in one gallery:
http://s292.photobucket.com/user/jsmithsmithj/library/Mazda%20B2600i?sort=3&page=1
A few months ago, I started a thread about replacing my 1992 Mazda B2600i's cylinder head with a newly-manufactured aftermarket: [IMG]
http://www.mazdabscene.com/threads/35624[/IMG]
Work got busy, so I've only recently been able to continue with that project. Today, I moved the camshaft and rocker arms from the old head to the new one. I decided to use the caps from the new head as I figured the camshaft bore was machined with them installed, and I didn't want to risk misalignment if I used the old caps. As a result, I had to disassemble the rocker arm shafts and transfer everything across.
While I was installing the rocker arms and springs, I noticed some odd wear on exhaust rocker arms; there was a noticeable groove forming on the face that bears against the spring. Although less prominent, there was similar wear on the exhaust side of the caps.
Wear on exhaust rocker arm face:
[IMG]
http://i292.photobucket.com/albums/mm26/jsmithsmithj/Mazda%20B2600i/rocker2_zpsnqhsifhd.jpg[/IMG]
Wear on *old* exhaust-side cap:
[IMG]
http://i292.photobucket.com/albums/mm26/jsmithsmithj/Mazda%20B2600i/cap1_zpsppddg3yz.jpg[/IMG]
There is no such wear on the intake side rockers/caps. I noticed that one face of each rocker has a notch. On the the intake side, this notch faces the clipped end of the spring, which allows the rocker to ride against the spring without rubbing against the sharp edge of the spring.
Notch on rocker arm face:
[IMG]
http://i292.photobucket.com/albums/mm26/jsmithsmithj/Mazda%20B2600i/rocker1_zpsji4ozo5j.jpg[/IMG]
On intake side, notches face spring:
[IMG]
http://i292.photobucket.com/albums/mm26/jsmithsmithj/Mazda%20B2600i/intake1_zps1tvjwjiy.jpg[/IMG]
On the exhaust side, this notch is on the rocker face that bears against the cap. The flat rocker face bears against the spring, and it seems to be the friction with the sharp edge of the spring that is causing the wear.
On exhaust side, notches face cap:
[IMG]
http://i292.photobucket.com/albums/mm26/jsmithsmithj/Mazda%20B2600i/exhaust1_zps8fducqwn.jpg[/IMG]
[IMG]
http://i292.photobucket.com/albums/mm26/jsmithsmithj/Mazda%20B2600i/exhaust2_zpsylqtl1ti.jpg[/IMG]
It seems to me that the exhaust side rockers are improperly machined as the notch should be on the opposite face. Either that, or a flat washer is needed between the spring and rocker face. Has anyone noticed this issue before or is this normal wear that shouldn't be concerning?
Much appreciated!