valve adjustment torque and feeler woes?

[grahamkissack]

I can't find a figure for tightening down the nuts on the rocker arms of each valve on my 1980 911sc. I figure I just hand tighten with my 13mm wrench?

Also, are there any tricks to getting the feeler gauge back into the intake clearances to check them. I was able to on the exhaust valves but haven't been able to on the intakes. I bought my feeler from PP.

Thanks, Graham

[Rick Lee]

I think there should be a torque value for this in Wayne's book. I use the Island911 special feeler tool. I can't imagine using one of those lame factory tools for this job. If you can get it back in the to check, loosen it until you can and redo it. I actually use two feeler tools - one with .004 stock and one with .005 stock for double checking. For tightening the 13 nuts, I use an offset box wrench while holding a flat tip in the slot.

[oly]

Does anybody know what the 13mm adjustment screw nut torque should be?

Wayne's book gives a torque spec for the valve cover bolts of 5.9 ft-lbs. But there is no spec for the adjustment screw nuts.

[Rot 911]

Not sure if there is a torque spec. And if there was how would you be able to use a torque wrench while using a screwdriver to hold the adjustment screw in place?

[mtelliott]

Not sure how you would use a torque wrench in the first place. You have to keep the screw driver on the bolt as you tighten the nut. If you then try and torque the nut, wouldn't you risk the screw turning?

As for getting the feeler guage in there after you have it tightened for checking, I haven't had any success with the factory tool. I typically just keep the guage in there while tightening, and then check the resistance on the feeler guage and see if it still feels right before pulling it out.

Michael

[jimi_c]

The only trick is that you use the same approach each time with the gauge - get used to the position that allows the feeler to slide in. Here's my lame attempt to illustrate:




Also, if the intake valves are too tight, then you won't be able to get the feeler gauge in no matter what you do. Try backing the set screw out a little before you slide in the gauge and put a little oil on the blade. I've found that by backing off the adjustment screw you can pace the gauge and hold the nut with a box-end wrench. Then tighten down the screw with the gauge in and slide the gauge back and forth for resistance. Once you get the required resistance, try to be conscious of the amount of pressure you've applied to the set screw - this will become familiar and by the time you're done you'll be able to set the clearance very quickly.

[juanbenae]

i tried to get the "swoop" of getting the feeler in and out on a valve adjustment last time i had a shop do it while i observed/was trained/attempted. there is a definite method to getting it right. i tore two of the guys feelers before he "retired" me to watch. i think if you were to do it often you would get it down, once every couple years, not so much.

i now have mobil works come over and do just the adjust now. i take it all apart and just have a skilled professional swoop in and do the adjust. less than an hour for jimmy, for me, not so little (time).

a good man knows his limitation, and some might say i am a good man, others, not so much.

good luck.

[ckissick]

Originally posted by mtelliott
Not sure how you would use a torque wrench in the first place. You have to keep the screw driver on the bolt as you tighten the nut. If you then try and torque the nut, wouldn't you risk the screw turning?

As for getting the feeler guage in there after you have it tightened for checking, I haven't had any success with the factory tool. I typically just keep the guage in there while tightening, and then check the resistance on the feeler guage and see if it still feels right before pulling it out.

Michael

My response, exactly.

[yelcab1]

This is when experience pays. I use a box end wrench, 13mm and a screw driver. I hold the screw driver and turn the wrench until it is just tight enough. It is only 13mm nut, 8mm stud, the max torque for that size is 15lbs, which is not very much. Practice on a a non crtical bolt of that size until you get the feel of how much torque to put on with your hand.

For rechecking it, I almost never do. Get it right the first time, go on with your life. It is way too hard to slide that back in, and you will kill the blade if you try. I have never had any trouble with that. But, that is just me.

[KFC911]

Originally posted by mtelliott
Not sure how you would use a torque wrench in the first place. You have to keep the screw driver on the bolt as you tighten the nut. If you then try and torque the nut, wouldn't you risk the screw turning?

As for getting the feeler guage in there after you have it tightened for checking, I haven't had any success with the factory tool. I typically just keep the guage in there while tightening, and then check the resistance on the feeler guage and see if it still feels right before pulling it out.

Michael

Ditto for me too....

[Hugh R]

Very difficult to slide the feeler in with it adjusted. Just loosen and insert and adjust. Rechecking is difficult, but I do rotate the engine when done and give every one a calibrated "Shake" to make sure its not tight. You want to feel the slightest bit of looseness, at least thats what I do. I adjusted my valves yesterday with the engine out, took about 30 minutes and it was still difficult to see whats going on.

[oly]

My plan was to use a torque wrench with 13mm crowfoot on the nut while I held the screw with a screw driver. But I've never adjusted valves on a 911 so maybe this would not work.

I'm surprised that most people seem to do this job without a torque wrench. Of all the places that you would want to use a torque wrench, it seems like valves would be one of the most important.

[oly]

jimi_c,

Thanks for the picture! Does "Slide in guage here" refer to inserting the guage in a direction parallel to the drive shaft? And does "slide in this direction" refer to the motion that you use for checking for the proper gap?

Art

[yelcab1]

It is pretty much impssible to get the torque wrench in half of those places.

[makaio]

Originally posted by oly
My plan was to use a torque wrench with 13mm crowfoot on the nut while I held the screw with a screw driver. But I've never adjusted valves on a 911 so maybe this would not work.

I'm surprised that most people seem to do this job without a torque wrench. Of all the places that you would want to use a torque wrench, it seems like valves would be one of the most important.

The only reason I could see to use a torque wrench is to keep from tighting too much. When you loosen the locking nut you get a feel for how tight it was, and you really don't need that much force to keep them from backing off.

[oly]

yelcab1,

I assume that you are refering to not being able to fit the torque wrench handle in those places as opposed to simultaneously using a crowfoot on the nut and and a screw driver on the screw. Is that correct?

Art

[jimi_c]

Art, the first arrow shows the path of least resistance to getting the feeler gauge under the rocker arm and in the correct position to slide into the gap between the valve tip and adjustment screw. The second arrow is the direction to slide in order to fit the feeler blade in the gap. Try backing out the screw first if your having trouble, it may be too tight, or even closed. Also, don't worry about torque, just tighten it snug. All you need is the feeler gauge, a box-end wrench, a short stub flathead, and two cold beers.

[Early_S_Man]

Art,

I can't imagine trying to use a torque wrench on valve adjuster nuts on 911 intake valves, and using crowfoot wrenches would throw off the calibration, anyway!

This is a situation where experience on air-cooled VW engines really pays off! Four fingers on a box-end wrench gets it close enough every time!

[Bill in OKC]

I'm getting ready to adjust my valves for the first time. I've got the gasket set and the special feeler tool, now all I need is a mild day and a few hours of uninterrupted time. The local shop said it needs it bad so its getting done. The torque is one thing I hadn't considered - practicing the feel on a different nut for around ?10ft.lb.? is a good idea. A crowfoot wrench sounds good if there is room in there - I've seen hollow core socket wrenches, maybe there is a torque wrench made like that? As always, the Pelican Forum is a great source of information. P.S. I've got the beer covered.

[Wil Ferch]

Another hint...Porsche updated the tool from P-213 to P-213b or somesuch...but you can do the same yourself.
1.) take the blade off..and bend the blade holder to closer to 90 degrees.
2.) re-attach blade. use blue loctite or nail polish to prevent those "little" screws from coming off and ( horrors ! ) falling into your engine. You WILL have a bad hair day if they do !!
3.) at the other end of the tool...slightly recurve the curved section so it is a slightly tighter radius. Fits your "finger" a bit better.

Factoid... I miked the little blades that came with mine. Remember that the official spec is 0.1 mm, which roughly translates to .004". ( I think a little under). My measurements indicate all my blades were 0.0042 to 0.0045 "

Wil