valves adjusted to spec idles like an earthquake

[bastianshaw]

did two valve adjustments one on the m20 b25 @ .010
one on a m30b35 @ .012
both cars now idle like dogs shit
my friend says they need a valve job
if adjustments are deferred for a long time can that cause uneven wear on the valve stem?

I really dont see how setting valves conservatively at spec could cause this

[bmwstudent]

Did they run poorly before you "adjusted them to spec?" If the answer is no I would have to assume you did something incorrectly. If the answer is yes, maybe there is another problem.

[jlevie]

After work like this experiencing rough idle is commonly the result of the work causing intake leaks.

[bastianshaw]

After work like this experiencing rough idle is commonly the result of the work causing intake leaks.

yea but on 2 seperate engines?
I did notice he clamped the eccentrics down pretty tight "if you can get the feeler out, they arent too tight" was his reply; I read that "slight drag" was the goal...they are running really shitty like im not even driving them

[hoyabmw]

Always adjust them loose (Many go to .011, not .010). They are noisier, but idle way better.

[SmokeE30]

hows the wear on the rockers look?

[bastianshaw]

hows the wear on the rockers look?

i havent checked?
how do I check?

[jeffnhiscars]

i havent checked?
how do I check?

Pick a rocker that is in position to adjust (so has some play) and remove the retaining clip. You should then be able to slide it over and either pivot it enough to inspect or get a dental mirror. You are looking for scoring, flat spots or galling which is a sign that the case hardening is gone and you need to plan on replacing them