Valve Clearance Question

[same0027]

Hi all, I've read several threads on adjusting valves. I wanted to check mine as I have a slightly lumpy idle and off-idle stumble when cold. I used feeler gauges until I couldn't get one in and then went back one and called this the gap. I believe that was what I read for measuring procedure on another post. I wanted to check in on my specific measurements to get feedback from folks who know more than I.

Exhaust Side:
.38(.014)
.43(.016)
.38(.014)
.40(.015)

Intake:
.38
.38
.35
.43

What would folks that know more than I do? I read specs are .50 exhaust and .40 intake but that it was acceptable to run .45(+/- .05) on the exhaust and .35 (+/- .05) on the intake side to limit noise One forum said to never run the exhaust below .40. Should I leave all the intake valves and just do the 2 or 3 exhaust shims that are getting close to this minimal clearance?

[aj81spider]

The specs for an '81 according to the owners manual (and I assume the '82 would be the same) are:

Intake (cold): 0.41 - 0.49 mm
Exhaust (cold): 0.46-0.54 mm

If you measured right you have a lot out of spec, especially on the exhaust. I'm not really qualified to say how bad this is.

[RRoller123]

It is also important to know if the cams are original? For example, I have Allison's 274FI cams installed, and the specs are 0.010" Intake, 0.010-0.012" Exhaust. Quite a bit different than stock.

[same0027]

Thanks both for the feedback. I didn't have an owners manual so appreciate seeing the 81 specs. I assume it is a stock cam, I have nothing to indicate it's not. The cam towers are stamped USA on them so I think the head may have been rebuilt at some point but that's about all I know. I do have the special tool, I think I bought an older tool and on the exhaust side I have to move the engine backward, is that typical? The tool is not wide enough to fit the cam lobe through.

[RRoller123]

The "USA" mark is factory, not unusual. Not sure what you mean by the special tool. Is it a small, roughly horse shoe shaped device, fits in the palm of the hand?

This is one of the valve adjustment tools that is sold:

[same0027]

I've got a similar but vintage looking tool yes. I am committed to doing both the intake and the exhaust side at this point. I just measured 3 intake shims and it seemed like a full days work (actually took about an hour and fifteen minutes. I am having trouble getting the shims out. I think they may be rubbing the tool a little or are just a really tight fit in the buckets. Compressed air was able to get the first three most of the way out. I had to start the shim a little with a very fine pick. The fourth and rear most shim on cylinder 4 would just not come out. It started but is hanging up and compressed air and the pick are not working. My biggest issue is in trying to get a needle nose in there to get it out I often find myself pushing the shim back behind the cam lob, cursing a whole lot because I can't get back there with the tool in place, and then having to use a pick I pit a bend in to try to push the shim back until it is oriented again so I can either get a needle nose pliers on it or get it close enough to use the cam lobe itself to force it back into position. The one shim I did not have to do this with on the way out I had it happen on the way in. I am wondering my tool does hold the bucket down but it lets it rise up maybe halfway back to the cam lob. Is this typical? I do have clearance it is just a real pain and I barely have enough room to get it out. Should I try a different tool or is this just the way it is? Clearly I would have been happier having a bunch of shims on hand at this point as I'd be halfway done rather than still at the beginning but live and learn. Should it be this difficult to get the shims out of the bucket?

[18Fiatsandcounting]

Should it be this difficult to get the shims out of the bucket?

It shouldn't be, but it often is. I bought myself one of those tools pictured above, and tried it out on a spare cylinder head. It does work, but it's still tricky. The process was: 1) Rotate the bucket you're working on so that the notch in the upper rim is fully accessible, 2) Rotate the cam so the lobe fully depresses the bucket, 3) Insert the tool, 4) Rotate the lobe back out of the way, 5) using a dental pick* or the like, slide it into that notched opening and try to lift the shim straight up. Don't tilt it, but get the pick at least a half inch or so under the shim so that you can lift it straight out of the bucket.

*The right tool is critical here. I bought myself a set of dental picks off of eBay or the like, and they are extremely useful. The tool needs also to have the right bend in the pointy part.

-Bryan

[RRoller123]

A small neodymium magnet attached with some tape to the end of a rod, small screwdriver, stick, etc will lift them out. The magnets are amazingly strong, are only about 1/4" in diameter and maybe 1/8" thick.

And +1, definitely rotate the cups so the notch is accessible, and get a small non-scratching pry tip under there.