m20 valve to eccentric contact area

[zaq123]

Everything is stocko but no idea of age/mileage. I had the head overhauled 30,000km ago. They didn't mention worn cam or rockers, but I didn't ask.

See how your eccentric sticks out side the rocker arm? But mine doesnt. I'll go have a play with my spare head.

the amount it sticks out will be dictated by the valve clearance on the valve side or the rocker/cam clearance on the cam side), both things are relevant to each other. If they overhauled the head and used a reground cam and/or reground OEM rocker and OEM size eccentric - that's your problem. Remove the cover, look at the rest of them, check for proper clearance, check cam/rocker for any wear. If all the above checks out - buy OME oversized eccentric to see what it will do. Buy the rest of oversized eccentrics as needed if everything else is good. You still didn't say what is you valve clearance is set to

[e30davie]

Everything is stocko but no idea of age/mileage. I had the head overhauled 30,000km ago. They didn't mention worn cam or rockers, but I didn't ask.

See how your eccentric sticks out side the rocker arm? But mine doesnt. I'll go have a play with my spare head.

[zaq123]

I had a look at my spare head and yea something up with mine in the photo. Is it possible to put the eccentrics on backwards? I suppose it is given they eccentric. Maybe I need.to flip mine around.

No, they have no left/right side so that wouldn't do it. pop the cover and look at the rest of them. What can do you have, regrind? If everything is stock, most likely very worn cam (easy to see) or very worn rocker (not so easy to see unless disassembled) or something very very worn valve seat/valve (unlikely). What did you set your clearance to?

[e30davie]

I had a look at my spare head and yea something up with mine in the photo. Is it possible to put the eccentrics on backwards? I suppose it is given they eccentric. Maybe I need.to flip mine around.

[zaq123]

m20 valve to eccentric contact area

it's definitely off.

My pic:
HD rockers, new cam (not regrind), standard size new OEM eccentrics with 0.25 set valve clearance and OEM new hardware. Kind of hard to see with all that assembly lube but they are centered on the valve stem. This head had valve seats recut and new valve installed so that would in theory put eccentric closer to the edge (like in your case) but as you can see, it's negligible

[digger]

Going by my memory it looks off. Rotate engine and check the sweep.

[e30davie]

Hi All,

Doing the valve adjustment on my m20b23 on the weekend. Just maintenance. All of them were pretty good, had to adjust 3 or 4 of them slightly.

The one that gave me the most drama was cylinder 1 exhaust. Felt like i couldn't get enough out of it. At its current setting it was only just acceptable at 0.25mm. I probably would have liked to make it a bit tighter.

As can be seen from the photo the eccentric sort of sits on the edge of the valve. is this typical? I must admit it was getting late and i didn't take much notice of the others. Thinking back i probably should have.

I did remove the eccentric adjuster and it didn't appear to have much wear on it, hardly a mark on it to be honest. certainly no flat spot. I have another spare engine and i pulled one out of that too and that one was worn.

I put it all back together and drove to work this morning, sounds great and goes great. No issues to report and i have no intention of opening it again for another 5000 km or so. But figured the m20 boffins might be able to comment. My only thought was if Is this an indication of wear on the camshaft end of the rocker arm?