…so…what i said Maddy was that you would think mechanical metal to metal valve adjustment would be accurate…I continued…that oddly it never is…at least never the first time…even tho you measure all with micrometer and select correct shim…it just never comes out…as I said…and others…within 1/1000 is good enuf…you will chase 1/1000 many times over…BUT…you have some odd descrepancies in your clearances, I will need to go over my past notes on all to be able to list them…but initial measurment showed zero clearance on one…so a guess to select a shim…and it already had a thinnest shim, so you ground one down. Later…you had some where you replaced with a thinner shim…and instead of more clearance you got the same, or less. And so on…so this is the reason…along with that you spun the engine with one cam all attached, the other in place but off the sprocket…that as long as you have some clearance on all…even if off by 3-4 thousandths…I suggest not chasing it…until you run the compression test to see what you have…the step prior that I suggested…you have done…the by mouth blow test, the compressed air blow test.both with cams out all valves closed…, the rubber stopper test, the bore scope to look for debris, the magnet and vacuum again for debris…verifying cam alignment…and finally to do the compression test…IF…the comp test is OK…anywhere close to OK…then you can do another valve shim adjust to get all to within the 1/1000 of spec. From what I have seen of your clearance measeurments…please don’t chart as above…all we need to know now…is what shim is in there now…and what is the clerance now. I will deal with the issue …that you did put in some odd sized shims, and had some confusing results…and the why of that…later, below…I suggested that a shim may have been not rocking a little…so on the keeper…so measurements come out the same…or that a shim was cocked and not flat…has slipped sideways…
OK now for the anomolies of what you did and measured: example: example…intake #4 had a .099 shim in it…(was the replacement from your prior work-) your recent clearance check for intake #4 showed .003…very odd…it was .004 to begin with and you went from a .101 existing to a .099…to get more clearance…yet is tested less…, and now you say you replaced the 099 with a .109…a much thicker shim, ten thousandths thicker, …which would give you ten thousandths LESS clearance than the .003 that you had, not more clearance, : , but you say you re checked the clearance and it is now …008. . I sent you this…
Let’s start with this: which is stated over and over in the Adjust Document instructions…The RULE:
A Thinner replacement shim gives more clearance by the amount it is thinner.
A Thicker replacement shim gives less clearance by the amount it is thicker.
Think of shims
as Pringles in the tube. Make the pringle stack thinner (by removing some) and the clearance
at the top of the tube becomes more. Add some pringles to the tube (a thicker stack of Pringles)
and the clearance to the tube top will be less. )
so this is what you say you did …(copy of your email…my notes added.
intake #1 shim size .082 with final measurement of .008 Replaced with .076 final measurement .005.
(nick says: intake spec is 006, it measured .008 so it was 002 too much clearance, so to reduce clearance a 002 THICKER shim is the correct replacement, thus a replacement of the existing 082
with a .084 would have been the correct adjustment. Somehow you put in a 076 which is 006 THINNER…should have made MORE clearance…yet you measure .005. Something is rotten in
intake #4 shim size .99 with final measurement of .003. Replaced with .098 final measurement .003
(nick says…for the 003, initial, it would require 003 MORE clearance, so a thinner shim by that
same amount…003 thinner than the 099. so it would be a .096. --not a 098. It is possible
to put in a different shim size that is only 1/1000 different and have the measurable clearance stay the same. The correct shim should have been the .096, to gain .003 more clearance and achieve
the spec. 006.
exhaust #2 shim size was.108 with final measurement of (?) too tight for thinnest feeler.
Replaced with .092 final measurement is .015.
(Nick says: needed to have Exhaust spec of 008 and had zero.none…lets guess you needed .009 thinner
than the .108. (thinner gives more clearance),
so that would be a 099, say even a 098. But you went much further.thinner, by.006- thinner
than you needed…so ended up with clearance of .015, which is 003 too much clearance)
exhaust #4 shim size was .124 with a final measurement of .015. Replaced with .109 with a final measurement of .015. Not sure why.
(nick says: exhaust spec is 008. it initially measured .015. it was say 003 too much clearance
so the replacement shim would be .003 THICKER than the 124 to reduce clearance by that much.
The new replacement shim would then be .127. Why did you go THINNER from a .124 to a .109.
that is the wrong direction…and not only that, but a difference of fifteen thousandths…when it only needed three thousandths?, by .003 THICKER…not thinner. Needed to reduce clearance.
Now to the issue with this one…you changed shims b a lot…and clearance stayed the same.
Did that shim rock on the valve stem? Likely not…it seems the stem is so low that
the shim is not contacting the inside of the tappet. That is the ONLY way a shim size can
change a lot but not change the clearance…the tappet is not riding on the shim.
You said you were able to push on each stem and they moved.
You said no air escaped on the blow test. It seems it has to be one of a few things.
stem ground too short by prior work, stem bent and not fully returning to closed valve
position (but air would escape the open valve), valve edge damage-bent, where valve
does not fully close thus stem is not fully released…again…air would escape.
so…not only the wrong shims installed, but also the problem of exhaust #4 to figure out. If this all were going well…I’d adjust again…including the ones that are 1/1000 off…once in there, why not. But Exhaust 4 needs a close look…and it really needs to get to a compression test to see if it passes or not…could be chasing will-o-the-wisps if there is a compression problem and the head has to come off. So…that is reason for the bore scope look first, a magnet sweep, even a flash lite look…and then after all that to try to be sure there are no “bits” in there…the blow out the 6 stoppers test…