Valve adjustment to tight or to loose?

[1929fordtudor]

May be a dumb question, but I was wondering if it is better to stay around the .08mm clearance or to be around .04-.05? I ended up with 3 being in the .085 range, 2 in the .063 range and 3 in the .042 range. Any thoughts?
This is my first adjustment, and when I started, on only one valve was I able to get a .033mm gauge in there. All the rest had no clearance.
I can't wait to put it back together and feel the difference!

 

[Nessism]

I'd go with it. Call it done.

 

[hampshirehog]

The gap closes up with time and what you don't want is zero gap (= valves not sealing properly and burning out). Your gaps are now fine.

If you don't intend to check your clearances regularly go wide (up to .1 is fine, just makes a bit more ticking noise).

 

[Nessism]

...and this is what happens to your valves if you don't adjust them.

 

[BassCliff]

Hi,

You're within spec. You can be done if you want. But be sure to check them again in 4000 miles since you have a few that are close to the lower end of spec.

My smallest feeler gauge is .04mm. If it's a tight fit, or it doesn't fit, I swap the shim to the next smallest size and run at .09mm or .10mm (that's as loose as I'll go). I keep track of my shims and clearances. I try to run them all on the loose side of spec. That way if I can't check them for 6000-7000 miles I don't worry too much.

Thank you for your indulgence,

BassCliff

 

[jpaul]

I prefer to keep them at the wider end of the spec. In theory this will keep the valve cooler, since it will spend more timeresting against the valve seat where it can transfer the heat to the head. Probably splitting hairs on this, but that's my dad's theory, and he's a better mechanical engineer than me. On ones that are tighter than the spec range; as long as you can rotate the bucket you probably don't have zero clearance. I would get shims on order, but probably still go riding while waiting for them to show up.

 

[atchbo]

I dunno. I bet there are more valves with <0 clearance than one would think. I just stopped down a full size on mine and I still can't get my smallest feeler in there, so will have to go down another size. I could still rotate the bucket prior to starting all of this, so it must have been zero or less.