Math Confusion '86 3.2

[jackportia]

OK, bought the Kirk valve adjustment tool thinking this time it will be easier than the usual backside method fumble. Wrong. Follow Kirk directions put everything back together, start the car and stand back to listen to my mechanical wizardry. Expecting sewing machine I hear marbles in a can. This is not bigly!

Drain oil, strip back to the rockers and lie underneath this thing I love (not the position I prefer) and ponder. Check the backside gap at #1 and I'm in excess of .004, closer to .005. Reapply the Kirk, measure and get the same result. Running out of love I go back to the backside feeler gauge method of .0025 go .003 no go. Now I'm thinking I'm too tight and not looking forward to another sleepless night. Kirk or backside, trust gone.

Question. Why is the gap with the Kirk at .004 not the same as the backside feeler gauge of .0025/.003? What am I missing other than frustration?

Apologies for the sexual content.

[75 911s]

The Kirk tool is measured in MM and the mark is set for the gap at .1mm, where-as the feeler gauges are measured in thousands in this case at .004 inches or 4 thousands. They are close as .004 inches is equal to 0.1016mm. In my experience, it's the final tighten that can make the valves out of spec. If you tighten and move the clearance too much, your measurement is blown. This is where the kirk tool excels. You can clearly see any movement past the .1mm mark. It is also possible to mis interpret valve noise as an exhaust leak or possible chain box noise. Do you have oil fed hydraulic chain tensioners? or the non line fed older style? When's the last time you checked them? The seals are good for about 30 or 40k miles.

[yelcab1]

What is wrong with the old fashion 4 thou feeler gauge? Ask John Walker what he uses.

[jackportia]

Oil fed tensioners ('86 3.2). My question is after using the Kirk what measurement, metric or inches, should I have when measured backside. Backside .0025/.003 should give .004 at the valve tip. When I use the Kirk I'm not getting that measurement, I'm getting .004 which is my confusion.

[chris_seven]

I have never been sure about using the backside method it just doesn't seem the best idea.

I also believe that the Rocker Arm Ratio on an adjustable Rocker is 1.46 not 1.4.

We have carefully measured rockers on a CMM in the past and feel sure that 1.46 is correct.

This would mean that a 0.1mm valve clearance (0.004") would translate to 0.0027" which is about 0.07mm and I don't have a feeler gauge of this size.

A Go-No Go measurement is not too bad an idea but does assume that the rocker is accurate in all respects.

The Kirk Adjuster or similar has been around since the mid Sixties and was extensively marketed by a company called SPQR.

spqr tappet adjuster | eBay

They are still made by Gunson.

I have always thought that using this type of device can also be prone to errors and will generally stick to putting up with the inconvenience of measuring the actual gap.

[jackportia]

Thanks Chris. I understand that 0.1mm valve clearance (.004) would translate to a 0.0027 gap at the backside, hence the .0025 go .003 no go. I'm getting .004 at the backside with the Kirk. which is too loose. It may be my clumsiness with the Kirk which is a strong possibility, but I did double check. Thanks for your reply.

[jackportia]

As an update I would like to clarify that I am not disparaging the Kirk tool. It is obviously a quality product and if anything this will come down to user error. I'm going to double check tomorrow using the Kirk and the backside method and compare the gaps.

[Canada Kev]

How did your engine sound before you tackled you adjustment? Do you have a .004 tool?

I usually just measure the 4 thou. Sometimes I check with a go/no go. They're usually bang on. Perhaps you're having operator challenges with the Kirk tool? How many valve adjustments have you done? If this is your first, I'd recommend using the front side, under the rocker .004" method until you become comfortable with that, then move on to other methods.

[Hendog]

Timely thread; I just finished another adjustment yesteday using the backaide method. I've been using the backside method for some time now. I may have to strart another thread to post pics along with questions/concerns.

[jackportia]

Thanks for the advice Kevin, but the whole point of backside measurement or Kirk valve adjustment is a less stressful method than stuffing a .004 feeler gauge down the cam tower and trusting the "feel." Third valve adjustment using backside method. You are probably right about "operator challenges" thanks for pointing that out.

[Canada Kev]

I understand the point of using the backside method. And I do that on occasion. However, if you successfully adjust in the "traditional" way, it builds confidence and the ability to diagnose and troubleshoot other, perhaps easier and quicker methods like the Kirk tool or similar and the BS method. It gives you a known baseline to try the other methods. All other ways have a learning curve. I am not one of those that poo poo anything other than using the .004 gauge - find the method that works best for you - but I am of the opinion that you should learn the mainstream accepted method of anything first. Then take the "short cuts" to suit your own work flow. It can only make you a better technician.

[ChrisBennet]

When I adjust valves, I do a quick post adjustment check.

Before I put the valve covers on, I go through each firing position (like you do for adjusting the valves) and rock the rockers using my fingers ("click, click"). It's mainly a check that there is a gap at all but you may be able to feel if a valve doesn't "click" the same as the others I.e is tight or loose.

Is may be just me, but when I finish adjusting the 12th valve, torquing the 24the head stud, etc. I'm really happy that I don't have a motor with more cylinders. :-)

[T77911S]

Originally Posted by yelcab1

What is wrong with the old fashion 4 thou feeler gauge? Ask John Walker what he uses.

I have done both and trying to fish a feeler in there far the backside is just not worth it. in short, I don't ever loosen the nut very much, only enough to make very small changes because that is all you should ever have to move it.
I also use the angle of the adjuster as a gauge. usually its only 10-15 degree changes.
I set the drag very snug for the intake and a little loser for the out. as long as you can get the gauge back in the valve is not too tight.

I also think a lot of people over think or over stress on adjusting valves.

I don't drain my oil to do the valves. very little comes out. I also let the oil get a little low when I do it and none comes out.
also get the reusable valve cover gaskets. when the nut hits the valve cover it is tight enough. don't over tighten them