Adjust valve lash on unknown cam

[BillGrissom]

All I found perusing my 1964 Plymouth Service Technical Manual was pg 9-3:
Tappets - Clearance Valve Stem and Rocker Arm Pad (Engine Hot) 0.010" Intake, 0.020" Exhaust

I couldn't find a photo or description how to measure it, nor anything about measuring with engine running. From 1976 to 1994 (stolen), I owned a 1969 Dart 225, and began doing my own repairs. I now have a 1964 Valiant 225. I recall adjusting the valves cold and later checking while still hot, and no difference.

I wonder how you adjust with engine running. I imagine you slip the feeler gap in the gap and adjust until you just stop hearing a tic the gap. If not, please explain. I saw a mechanic do it once after a head job, with engine running. It wasn't flinging oil, so perhaps he had lowered the idle. I don't recall seeing him use a feeler gage, but perhaps had earlier. Seemed he was tweaking them by the ticking sound, but didn't watch close. That was 1978, back in the day when every mechanic knew the slant.

My 1985 M-B diesel has a solid valve train (OHC with "follower" which pushes on valve stem). One doesn't adjust with engine running, per the fastidious M-B procedures. I recall best to do with engine hot, though I recall doing both "warm" and hot and no difference.

 

[66fs]

All I found perusing my 1964 Plymouth Service Technical Manual was pg 9-3:
Tappets - Clearance Valve Stem and Rocker Arm Pad (Engine Hot) 0.010" Intake, 0.020" Exhaust

I couldn't find a photo or description how to measure it, nor anything about measuring with engine running. From 1976 to 1994 (stolen), I owned a 1969 Dart 225, and began doing my own repairs. I now have a 1964 Valiant 225. I recall adjusting the valves cold and later checking while still hot, and no difference.

I wonder how you adjust with engine running. I imagine you slip the feeler gap in the gap and adjust until you just stop hearing a tic the gap. If not, please explain. I saw a mechanic do it once after a head job, with engine running. It wasn't flinging oil, so perhaps he had lowered the idle. I don't recall seeing him use a feeler gage, but perhaps had earlier. Seemed he was tweaking them by the ticking sound, but didn't watch close. That was 1978, back in the day when every mechanic knew the slant.

My 1985 M-B diesel has a solid valve train (OHC with "follower" which pushes on valve stem). One doesn't adjust with engine running, per the fastidious M-B procedures. I recall best to do with engine hot, though I recall doing both "warm" and hot and no difference.

It is not in the service manual. I was taught really smart mechanic. I thought it was common knowledge until the Brewhaha. Before everything went to hydraulic lifters, valve lash adjustment was part of a major tune up. The feeler gage will slip in at the lowest point, theoretically the base circle, and "grab" the feeler gage as it starts to lift, no big deal. You just ignore when it grabs. It is only for factory friction adjusters without lock nuts. You can do it anyway you want. They all work. The +.002 for cold is to compensate for thermal expansion when going from cold to hot. I tried using the chart, but when I double checked the lash, it was off. Not too far, but it was off. I'm sure the base circle was not uniform, so I went back to the old way. Cast Iron heads are different than Aluminum heads and I don't run aluminum heads, so no experience there.

The guy that was not using a feeler gage was probably one of those guys that had his own system for speed, time is money in the mechanic world. He was probably dead on. I've seen people do things that made no sense and when you check them they are dead on.

 

[hotrod swinger]

I like doing things the old school way sometimes. That’s why I have an old car.