Valve Adjust Technique...

SummerSledSix · 07-20-2002, 05:01 PM

Had the engine out to replace the gaskets and insulators on my intake runners and the O-rings on my fuel injectors (air leak). Decided to tweak the valves (my second time at this) while I was at it.

Put the engine back in, fired it up, got a knocking sound right away (no such sound before I did all this). Called the local braintrust, "check your adjustment". Dropped the engine AGAIN (BTW, anybody with a six, ie a 3.2, able to get the lower rocker covers off WITHOUT dropping the engine?), tweaked the valves AGAIN (exactly per the tech article), and checked the runners / injectors. Got the engine back in, fired her up, pretty quiet until she came up to temp, now the knocking sound is back, though not as loud. Sounds like it's on the 4-5-6 side.

Two questions: can anybody "decode" the knock thing for me? Also, and this the bigger question:

How "tight" should the feeler gauge be clamped in between the rocker and the valve stem when you are setting the gap? How do you tell where the sweet spot is??? Seems like my more recent effort was better than my earlier one, but I don't know why...

ein 6er · 07-21-2002, 05:09 AM

john,

i'm the crusty veteran of .... ahhhh .... one valve adjustment, (on the 911 engine). after finishing mine, i went back over it again to double check my work and needed to tweek a few adjustments. i realized on the first go around, my mistake was not making sure the rocker was pushed down tight onto the cam. at the time i did mine there were some great threads on the 911 board with some of the gurus offering advice. i think it was j. walker that recommened snipping the corners off the feeler gauge and fileing any burrs off to make it easier to get the gauge in, (i didn't do this). also if you bend the blade it will crease and you can't get an accurate adjustment, so it needs to be changed, that's why you need extras. and as those guys said, it takes a while to get the "feel" of how tight the guage should be, rookies tend to err to the loose side. but if it's too tight, that's when you can bend the blade.

are you using or have you heard about the "new" adjusting tool? a guy on the 911 board ("island911", i think) had some made. they are suppose to make the adjusting process a bit easier.

the lower covers on my old engine were a pain to get off. i wish i had your "problem", (3.2). if you are using the turbo valve covers, i've read that the fins need to be milled down on one end, ( this you probably know).

if you have ruled out the valves causing the knocking sound and you only hear it after warm up maybe it could have something to do with the injectors? (preingition?) maybe unplugging one injector at a time or checking the injectors output.

a lot of guesses here, i'm sure someone that knows what they are talking about will jump in with help!

good luck!!

doug

SummerSledSix · 07-21-2002, 06:20 AM

Hey Doug, thanks for the reply! I learned about the "island911" adjuster when I was searching the threads on this topic, but I didn't see anything about milled valve covers. Can you tell me more, or point me in the right direction?

My lower valve covers are "turbo" (I think all lowers were by the mid '80's), and the uppermost rib(s) hang up on the inboard trailing arm mount. Seems like if I milled a "divot" in the rib(s), they would come out, but I don't want to ruin them either...

SummerSledSix · 07-21-2002, 07:55 AM

After trying a few search terms and wading through a LOT of threads, I came upon a post by JP a few weeks ago re: hacking the valve covers. Guess I'll get the belt sander out and say a few prayers...

Figured at the very least JP and / or Jim Smolka would have BTDT, and it goes to show that just about every topic has been discussed here AT LEAST once, the trick is finding the thread...

ein 6er · 07-21-2002, 10:44 AM

yessssssss ..... search and yeee shall find!!!

check this out, i knew i had seen a foto of the covers somewhere!

http://www.pelicanparts.com/techarticles/911_turbo_covers/911_turbo_covers.htm

i have a '67 2.0 in mine, the heads only have 6 studs and aluminum valve covers, the ribs aren't as deep as the turbo covers and mine just barely come off with a lot of wiggleing.

good luck,

doug

SummerSledSix · 07-21-2002, 11:25 AM

Doug, thanks for reply. I hate cutting OEM metal, but if it's in a tech article, then its OK by me.

jabb · 07-21-2002, 04:27 PM

Hi John:

You definetly have to file down the valve covers on the 914
in order to get them off.... I do not reccomend doing this while in the car. Take the Engine out and covers off an file them, Filing them in the car will lead to lots of fine Aluminum shavings floating around into your engine...... Follow the tech article on valve adjusting and you should be ok I marked the flywheel with RED paint to indicate where 1-2-3-4-5-6 are, easier than trying to find the marks on the front pulley should you try the adjust the valves next time wiith the engine in the car......

Good Luck

SummerSledSix · 07-21-2002, 04:33 PM

I'm getting REAL good at dropping that !@#$ engine. Guess I'm going to get a little more practice...

J P Stein · 07-21-2002, 05:37 PM

Here's a (lousy) pic of the front pulley marked up......this is 1 & 4
in yellow.

and yes, there's a hole in my firewall.

To adjust the valves while the motor is car, I raise up the car to a comfortable height, block one wheel, put the trans in gear, and turn the other wheel.......rolls the motor over nicely. When the 1/4 mark is at TDC, either 1 or 4 rockers will be loose.....let's say it's #1..... turn to the next mark, 6/3 & do # 6 then 5/2 yada, yada. Twice around, and we're done. Those without firewall holes
can see the marks with a mirror.

Drop the motor to set valves....I'd rather eat slugs

SummerSledSix · 07-21-2002, 08:25 PM

JP, thanks for the pix.

Got any wisdom on the loose / tight calibration when you're doing the valve tweak itself?

I've been backing out the screw, then twisting it back in with the feeler gauge in there, until I feel the screw starting to bind, then tightening the jam nut. Is that too loose, or too tight?

Also, how hard do you need to honk down on the jam nut - I haven't found a torque spec anywhere, assuming I could get a torque wrench in there to begin with...

J P Stein · 07-21-2002, 09:07 PM

Wisdom?......er....sure.......it ain't called a feeler gage for nuthin'

.

I set the lash (stick the gauge in there and run the adjuster tight with my fingers...that would be finger tight, I guess), hold the adjusted with a big assed screwdriver and honk down the nut with a regular 13 mm box end wrench, all the while leaving the gauge in place.....then check it again and hope the "feel" is gud. Feels gud to me bout half the time. Redos on the others till I get it. Mostly, now that the cams are bedded in, the lash doesn't change much. Most require that I leave well enuff alone

If .004 goes and .005 don't........PFCE, me thinks.

Getting them to +/- .001 doesn't seem to be all that tough. One of these days I'll check myself with a dial indicator.
I do this bout once a year. I don't put many miles on my car and it isn't my favorite job.

si2t3m · 07-23-2002, 11:29 AM

I've done mine with the feeler gauge thingy. They could probably use anothr ajustement...

Anyway, i'll be back in there but this time with a dial indicator. Seems much easier to see the gap than to feel it.

Belt sanded to ribs too on the turbo valve covers in hope to do the job with the engine in place.

Just hoping i'll be able to ajust them with the dial indicator & heat exchangers in place...

Marc-Andre Morin
70 914-6 conversion 3.0L Webers

6 Shooter · 07-23-2002, 03:21 PM

FWIW, when I installed the turbo valve covers on my car, I did it with the engine still installed. That way , I was able to see how much I needed to file (I didn't use a belt sander) off each cover. Also, I was able to see where I needed to file so I would be able to remove the lower covers with the engine still in the car. Another reason is to remove the minimum amount of ribbing/reinforcement since the ribs are the reason for the update. There might be slight clearance differences between different cars (and side to side), but then I was A.R. way back then, and probably still am. I didn't worry about aluminum filings falling inside my engine, since: these are the LOWER covers that need clearancing, I filed each cover next to the car (probably on a work bench), and if there were any filings still on the outside of the cover (next to/between the ribs), they would fall down/away from the engine/car. HTH.

Roland Kunz · 07-23-2002, 03:34 PM

Hello

Using thick Valvecovers on the 914/6 is possible if you machine the fins down like on the 930 driver side unit so you have a bit more air to the inner axle nut.

Then remove all the lower studs and use bolts to hold the valvecovers. You have to use helicoil inserts in the threads for long term durability.

Grüsse