Valve adjustments

MikeP · 11-15-2001, 08:06 PM

First I want to thank all you guys for you help. This is my first porsche, and by far the deepest i've ever been inside an engine. Everyone on here has helped me out through several problems, and pointed my in the right direction. Thank you!

So heres my dilema:
While setting the valve clearance, #2 and #4 cyclinders have no slack in the intake valves. If i back the adjusting screw all the way loose it doesn't open the rocker enough for an electron to past through let alone a .010 inch feeler gauge. The marks on the flywheel are lined up perfect. Am i forgetting or overlooking something?
Heres my proceedure. First I set #1 on TDC. Next rotate the crank counter-clockwise 180 do #4, rotate 180 do #3 and finally roate and do #2. Counterclockwise is what the book says, is this correct? Are 3 and 4 backwards. I've been starring at it all evening and can't figure out why. I looked inside through the oil pan and all the push rods are seated correctly on the lifters. Any help you guys can give me would greatly be appreciated, because I am close to float testing the damn thing!

Rot 911 · 11-16-2001, 07:33 AM

I suspect you don't have things in the right order. Try turning the crank 180 degrees and see if the rocker arm opens up. If not, turn another 180 and see if it does.

WFBowen · WFBowen's Garage

Mike: If I were you, I'd do a valve adjustment the hard way, from scratch, since things might have gotten out of whack. First, bring #1 to TDC. It's important that TDC is on the firing or ignition stroke. Lift the distributor cap and make sure that the rotor is pointing to the #1 cyl. stud on the cap. If not, rotate the motor again until it's on TDC on the firing stroke. Also, when you're "under the car", always check that the cyl. on which you're about to do the adjustment has both valves closed. Unlike Detroit iron, etc., it's critical that everything's done fexactly to specs, including a cold (overnight) motor. Take it slow & methodically - I've known seen some of the best race mechanics/tuners get distracted while doing such jobs and they just start over. Grab some coffee, turn on the stereo & take your time. Half of the pleasure of Porsche ownership has always been working on them.
Good luck.

josh912 · 11-16-2001, 01:58 PM

Your doing everything right, except you adjust the valves in the order 1-2-3-4, not 1-4-3-2. I would also suggest looking at Wayne's instructions http://www.pelicanparts.com/techarticles/356_adjust_valves/356_adjust_valves.htm Good luck!

Jones Low · 11-16-2001, 03:43 PM

Make sure you have the cylinder numbering correct.
Cylinder #1 is the front passenger side, #2 is rear passenger side, #3 is front driver side, and #4 is rear driver side.

At top dead center for cylinder #1, the distributor rotor should line up with mark on rim of distributor and the crankcase seam with the notch on crank pulley. Now adjust valve clearance on intake and exhaust valves on cylinder #1. The push rods for these two valves are the first two of the four on the passenger side closest to the front of car. Closest rod to front is the exhaust and the next one is the intake.

After adjustment of #1, rotate the crank counterclock wise 180 degrees by turning the big nut on the generator. Crank notch will be at the bottom, distributor rotator will move 1/4 rotation (Some of us file a notch on the crank pulley for reference).

You are now ready to adjust cylinder #2, last two valves on the passenger side most rear of the car.

Rotate counterclock wise again, and you are at #3, front first two valves on the driver side.

Continue with #4.

If you are still not sure of the firing order and alignment of valves, remove both valve covers, and have someone rotate crank (by hand, ignition off)while you study the pushrod action and you'll have a better understanding.

Jones Low
69-912

MikeP · 11-16-2001, 09:49 PM

Ok I got all the valves adjusted correctly. Thanks for the help guys. I found the problem! I was turning the crank counterclockwise as my book dictated. But as i studied the valves as i rotated the crank i discovered that the engine actually rotates clockwise. This is opposite from what the book says. What gives? Am I right?
mike

Jones Low · 11-19-2001, 07:56 AM

The crank normally rotates clockwise when running is true. But some of us are lazy! By starting with cylinder #1 and turning the crank counterclock wise you can adjust the valves in reverse firing order, staying on the same side of the engine when adjusting the valves. This helps if you are doing the valve adjustments on the floor and on your back. By doing this, you can adjust the valves on cylinder #1 & #2, move to other side and do #3 & #4. After the adjustment I go through another cycle to verify the clearance again. It doesn't hurt to rotate the engine backwards when you are doing this.

Jones Low
69-912

MikeP · 11-19-2001, 08:59 AM

Hey thanks Jones. That makes sense! My porsche manual is absolutly crap. The index doesn't even match the page numbers, let alone give details like 1234 instead of 1432. Oh well. Thanks for the help.
Now i have another problem. The engine is back in after new heads and rings. And well....she doesn't want to start!!
Its always something.
Thanks again for the help
mike