CD - I fall on my unadjusted valve stem!

[BillWilliams]

I am still learning about these cars, tiis, specifically.

The yellow little car's motor is not new any longer. Rebuilt in 2002 and has many kms on it. Been to CO and back, many trips up your way and many more trips down south. I drive it every week if salt is not on the roads.

The yellow car still runs and starts fine. Not a screamer but it keeps up with the pack.

My question asked with all due respect and in a sincere learning mode. Why do you always insist on adjusting valves?

That is something I have never done and do not know how to do with confidence.

Obviously you feel that is critical. What are symptoms of unadjusted valves?

I need to have someone demonstrate how to adjust valves so I can feel comfortable adjusting them.

[2761876]

Bill,

Though no CD, I have some thoughts.

With all of your wrenching expertise, as evident on your beautiful stable, adjusting the valves should be a piece of cake.

Some symptoms of valves out of adjustment are a slight ticking from the valve cover area and a tired feeling engine.

My tii had no ticking, but at 40k seemed a bit sluggish and hard starting. After the valve adjustment it was like new!

Heres the faq valve adjustment link;

http://www.bmw2002faq.com/content/view/21/32/

You can do it!

~Nate

[dubois]

Bill,

I am sure CD will chime in with a good/ better answer.

I often had the same question. 10k after engine rebuilt, I opened the valve cover and found one or two valves that were too tight or too loose. Too tight or too loose are not good for the motor. How do these things move out of spec? Well we are only talking .001" (a hair is .003"). There are probably several reasons.

What is in actuality done, is mostly a check up, and maybe adjusting a few valves. After a while, you can almost tell (by moving the rocker up and down) which ones are the ones that need readjusting. So the job doesn't entail adjusting ALL the valves, just the ones needing it.

MAC tools sell some nice filler gages, they are angled and have two thickness, like a go - no go gage, makes the job a lot easier.

BTW: what a delightful way of asking a question.

[MatthewCervi]

Bill, I've done it lots of times. I could come over and show you tomorrow (Sunday) afternoon if you want. The engine just needs to be cold.

[jimk]

My question asked with all due respect and in a sincere learning mode. Why do always insist on adjusting valves?

Seem like the respondants so far are so prowd of their ability to adjust valves, they didn't answer the primary point of your question.

Intake valves typically wear to tighten the adjustment gap. As the operating temperature of the valve gets really hot in operation, the stem grows in length. If the gap goes to zero, the valve will not seat in the head and will leak back. When combustion occurs, the flame will leak out and "flame cut" the valve and seat, leaving compression loss and a "burnt valve".

Exhaust valves can settle in either to tighten the gap or loosen, depending on the amount of combustion deposits on the seating surfaces of the valve and valve seat. If it tightens, same results as for th intake. If it opens the gap, things get noisy. The noise comes from parts slamming together when the cam begins to lift the valve because the lift begins too late on the cam profile. This impacting can caust premature wear on the cam, fracture of parts like the rocker.

Enough explaination? The book would not require it if it wasn't good maintenance. Procrastinate and suffer the consequences!

[c.d.iesel]

THE HIGHER AND STEADY THE VACUUM READING AT IDLE -

the healthier yer motor. Just like you own paulse/heart rate/respertory/O2

reading.

read this explaination about motor 'tuning' using a vacuum gauge

http://www.secondchancegarage.com/public/186.cfm

BEFORE ANY MOTOR REPAIRS ARE EVER ATTEMPTED !

ONE MUST ASSURE THAT THE VALVE CLEARANCE IS CORRECT,

NO GALLALING OR WEAR OF CAM LOBES, CAM/ CRANKSHAFT

TIMING ARE SPOT ON.

Any one of these points out of line and your wasting your time, chasing your tail, pissing-into-the-wind, and loosing horse power.

By using a simple, inexpensive vacuum gauge - your valve timing,

fuel system air/fuel ratio, burned valves and seats, malfunctioning EGR

emission syltems, incorrect ignition timing are revealed.

Compression test is also AS IMPORTANT BEFORE ANY REPAIRS.

WHEN YOUR NEW TO AN OLD CAR - THESE READINGS ARE YOU BASIC BASELINE against all future adjustments and improvements or loss in performance.

This is basic 101 in motor tinkering

if you attach a vacuum gauge to all of your cars intake manifolds -

you learn patterns and understand healthy VS sick running.

MEASUREMENTS ARE YOUR STARTING POINT

When road testing with your Air/Fuel ratio meters or other

Co/HC exhaust read outs - a vacuum gauge reading

tells you precisely where your throttle opening is. You need to repeat that partial throttle vacuum reading/rpm/trans gear for repeatibility in adjustment comparison. IMPORTANT whan changing WEBER jets, KUGELFISCHER adjustments. It is your personal on the road DYNO.

more later if you want....................

Creighton

[BillWilliams]

I have a go no go gauge and On Star Mike Pugh is making me the "tool" from a coat hanger, instead of using an allen wrench.

Matthew, I will take you up on your offer but can't do it tomorrow. We will talk.

Need to put one of those vacuum gauges on the Christmas list.

[MatthewCervi]

I have a go no go gauge and On Star Mike Pugh is making me the "tool" from a coat hanger, instead of using an allen wrench.

Matthew, I will take you up on your offer but can't do it tomorrow. We will talk.

Need to put one of those vacuum gauges on the Christmas list.

Yeah, I use a bent wire. Coat hanger is just the right size, too. Just let me know.

Matthew

[winstontj]

Bill,

It is important not to overtighten the eccentric nuts. I THINK its ~9ft/lbs of torque but the number slips my mind. Its less than you would think it is.

Baum tools sells a beautiful low range torque wrench with boxed-end inserts that fit our application perfectly. The tool was ~$300 with the English and Metric open and boxed end wrench inserts. worth it IMO but the price is steep.

Hopefully CD or someone in the know will chime in and give the proper torque specs.

Best,

TJW

[Harv]

I have always used the bent feeler gauge and just stuck a alan wrench in the hole on the eccentric for adjustment. After loosening the adjuster lock nut of course. Adjust each one at the firing point of that cylinder. Or you can adjust the valve on the back side of the cam lobe.

Poor idle and valve train noise seem to be the main result of worn seats and stretched valves.

John

[Guest Anonymous]

I wrote, and rob edited (make sure you have a new gasket) an FAQ for adjusting valves. The reason you adjust your valves is so they open at the right time. Over time valves can tighten or loosen depending on if they are intake or exaust. This not only means you can loose some compression or make it harder for the exaust to excape but can wear out your cam shaft. This does not take very long to start and once it does then you need a new cam. needless to say the performance and saving your cam is very important.

Sam Schultz

see ya at V@V

[BillWilliams]

and I can coordinate our schedules.

[TobyB]

CD- you're right on.

Add to your compression test (hot, with the throttle propped open)

a leakdown test. Takes another 10 minutes max, and now

you know WHY your compression is as it is.

If a motor's been sitting for years, especially in the wet, usually one or

2 holes will be low on compression from surface rust on a valve seat. Might

LOOK like a bad motor on a compression test, but leakdown will show which

valves aren't sealing.

I love this place.

t

[Guest Anonymous]

. What are symptoms of unadjusted valves?

quote]

'02 and the E21 about 6 months ago - both cars developed erratic idle characteristics, both turned out to have one at least one valve at essentially zero clearance. With the valves adjusted correctly, the normal idle returned.

One other factor that I don't think anyone touched on - it's not too unusual for a high mileage motor to have flat spots worn on the rocker arm eccentrics. Once this happens, if the proper clearance falls on the high point between flat spots, the affected valve will start out with proper clearance, but can have the clearance open up (get loose) very quickly, as the narrow high spot gets pounded down.

If you're trying to keep a high milage motor running for a while, check the surface of the eccentrics where they contact the valve stem - if they've got lots of little flat spots worn into them, consider replacing 'em - they're cheap, and can avoid a lot of frustration with valves constantly going out of adjustment.

[tjones02]

1) loosen the adj. nut then with the bent rod in the ecentric tighten the nut until some resistance is felt when turning the ecentric. Having some tension on the ecentric helps hold it in place, so it doesn't flop all over. Too much/tight and you can't turn it and can't adj. it smoothly.

2) I like to leave the spark pugs in and use a remote start switch. (Gearbox in Neutral and Park Brake on! :-P ) I start with #1 exh. and #4 int. at the same time with the "on bottom of cam lobe" method by "bumping the motor over with the button. With another quick "bump" of the remote start button you're ready for #1 int. and #3 exh. and so on......

3) I always check all valves again after turning the motor over a few times with the remote start button. Sometimes even I miss one. :-)