912E valve adjustment

eki912 · 03-13-2003, 03:53 PM

I adjusted the valves , did it with 914 instructions.Ofcourse they did not apply 100%. After adjustment I started wondering , did I do it right? I started by finding TDC from distributor notch , for cylinder 1 and so on.... but now that I started from this marked spot in distributor was that really the TDC of cylinder 1? Since the ignition timing is 27 degrees BEFORE TDC , did I do it wrong by 27 degrees? And does it even matter? Any better way of finding the starting point (TDC) ?

e k i

WFBowen · WFBowen's Garage

eki:
The best way to determine TDC is to first rotate the crankshaft pully to the TDC mark and look at the rotor. If it points to cyl #1 the motor's at TDC. If it doesn't, you're 360 deg. off & need to rotate the crankshaft again. After adjusting #1, you can rotate the crankshaft 180 backwards and do 2, 3 & 4 (reversing the 1432 firing order.) The safe bet is to always go with the crankshaft and use the rotor as a indicator that you're on the firing stroke. Most owners paint marks on TDC and opposite at 180. As for your 27 deg. ignition advance, that doesn't occur until about 3000 rpm, so your adjustments are probably good. You can double check them to be sure, but if you had some slack on each rocker before adjusting (i.e. both valves on that cylinder are closed for the compression/ignition stroke) you're okay.
If you're anything like me you'll probably want to re-check them just to be absolutely certain.
Good luck,
Bill.

eki912 · 03-16-2003, 05:19 AM

I started by turning the fan to 0 mark on timingscale , but the distributor rotor was not pointing STRAIGHT to this mark in the distributor body.So I did it with the distributor mark only.And there was some slack on every cylinder when I adjusted them , so I believe I was not so badly off.... but I think I will do it again.Just to be sure! Any other ways to be sure about this TDC spot?

e k i

eki912 · 03-16-2003, 05:21 AM

UUUPS , naturally I meant there was some slack on each rocker when I adjusted them. ( not on cyliders.... )

e k i

WFBowen · WFBowen's Garage

eki:
I think that you're about a close as you're going to get. The crankshaft (fan) marks will always be the more accurate means of determining TDC, using the dist. rotor as a guide to which cyl./stroke you're on.
Bill.

snowman · 03-17-2003, 10:08 PM

You go by the crank shaft marks. Period!!!!

Thats the only accuate marks there are. The valve lash may be slightly off at this setting, but thats where it is set. By slightly off I mean that if you find the point where the lash is the least, and use it, you are wrong! You set it like the factory did, at the crank points.

eki912 · 03-18-2003, 06:28 AM

The sad thing is , that my engine was missing the timing scale.I bought one from VW , which looks the same , fits in nicely , and I believe will show the correct degrees. ANd then tried to adjust the ignition.... there where several painted sponts on the fan! So I am not sure if my ignition is PERFECTLY positioned either!!! You say crank shaft marks ? The painted spot(s) on fan you mean , OR? I wouldn´t mind knowing how to be 100% sure that I have this TDC spotted and marked on the fan.

e k i

WFBowen · WFBowen's Garage

eki:
Try this: Look for a black plastic cover cap near the center of the fan housing. If you still have your smog pump, it would be under there. Removing this cap will allow you to look straight down on the fan (at its forward side.) If you have it & removed the cap, remove the #1 cyl valve cover & using the front timing marks & ign. distrib. rotor, bring cyl. 1 to what you have assumed is TDC on the ignition stroke. Now, looking straight down into the inspection hole on the fan housing, look/feel for any mark or notch in the fan. Turn the motor by hand a few degrees either way to find it. If you find a mark, center it in the hole & mark it. This is TDC on #1. Now you can mark the other side of the fan or mount your timing guide.
Hope this helps
Bill.

eki912 · 03-18-2003, 11:51 AM

Well , this is the kind of information I was searching for! I have black plastic cover already missing. I have even thought about this hole , why is it there? Now I know! I only hope I can see/feel this notch or mark there... this notch , is it ( should it be ) easily visible? I will try to find it as soon as I can.

e k i

WFBowen · WFBowen's Garage

eki:
If your cap's been missing, chances are the inside of the fan has lots of "patina" on it. If you can't find the mark, might be a good idea to yank the fan (may as well put on a new belt while you're there since most of the stuff comes off for replacement) then clean it up & find the mark. Once you've found it, you can clean up & paint the outer (car rear) side & establish new, accurate marks that you're sure of.
Good luck,
Bill.

porsche912e · 03-20-2003, 07:10 AM

Bill,

In your response you say: "Now you can mark the other side of the fan or mount your timing guide."

Just to confirm: When #1 is at its TDC does the other side (i.e., opposite side) of the fan need to be marked?

And is there a way to check the timing w/o taking off the smog pump?

Thanks,
Dirk

WFBowen · WFBowen's Garage

Dirk:
Sorry for the foggy description. I'll describe the fan as 1. frontside :towards the front of car, inside the housing and seen only through the access hole; & 2. Rear: the part you see while looking towards the front of the car.
The frontside should have a mark on it . Once this mark is up on top, as seen through the hole, and the dist. is pointing to #1cyl, the motor is at TDC on #1. Without rotating the motor, you then need to mark the other (rear) side of the fan outer rim with a mark which lines up with your "0" degree mark on the timing degree guide. Make a second mark 180deg. off, in another color or pattern for valve adjustment. What's a little confusing is that this mark will not be at the very top of the fan, but maybe around the 11 o'clock area. Once the rear is marked, the car is timed from the rear using the degree guide.
The reason I did a fan removal when I had mine is that, over the years, PO's paint/scratch on various marks (some are just tool scratches) & you really have no idea where true TDC is. So I'd try:
Bringing the car to what is considered TDC. Temporarily mark the orientation of the fan, just to have a fallback. Remove the fan, clean it up; find the inside mark & clearly paint it . Paint the rear of the fan rim black. Re-mount the fan, line up the frontside mark, then paint a fresh mark on the rear side corresponding to the "0" on the degree guide. If you really want to be sure, pull #1 plug at TDC, with cold motor insert a plastic drinking straw into the plug hole & slowly rotate the motor back & forth until the straw is at its highest point.
I've never owned a 914-4, but I've got the feelilng that they're timed from the top (using the access hole) whereas the 912E is timed from the rear, since it's more accessible.
Good luck,
Bill.

tronman · 03-20-2003, 08:54 AM

Eki,

Where in Finland are you located? I've spent a LOT of time there over the past couple of years...God I love MidSummer Festival!!! All I can say is beautiful country...have a nice cold Lapin Kulta for me!!

Jake Raby · 03-21-2003, 11:06 PM

The valve adjustmet specs for a 914/4 are the same as your 912E. There are no differences, the engine internally is a 1976 914 spec engine, just with a few funky parts..

eki912 · 03-22-2003, 03:51 AM

Tronman , I am not in Finland now.I work here in Washington D.C. I bought my 912E here , intend to take it back home eventually.I will go to my vacation next summer , will have few cold Lapin Kulta´s too.... I think this information should be enough to do the valves properly!!! Or then confuse me completely... 914 valve instructions were used , when I realised that for example the engine is other way round... I am NOT an expert! Just learning the basics!

e k i

TonyB · TonyB's Garage

There is a large notch cut into the flywheel that also indicates tdc for #1. There is a cutout at the top and bottom of the transmission (on a 901 tranny anyway) and you can feel this notch. The fan can (should) only mount in one position unless the locating pin has been removed. With the car lifted, battery disconnected, one wheel in the air, the other blocked, e-brake off, trans in 5th, turn the free wheel to rotate engine over. Reach over the top of trans where it mounts to motor and feel for the small hole in trans. Once found, put your finger in it and feel for the large notch. It's obvious when you find it. You can get the motor close by using the distributor so you can roll the motor a little in either direction to find the notch. The notch on the flywheel is in the same location as the "0" is supposed to be on the fan.