: Noise coming from LH head - valve?



eisler99
04-05-08, 12:32 AM
Greetings to all. Been a long time reader here - great place. :thumbsup:

Could use some advice please. 93 STS 100K - 1st time car is out of service for me.

I have a new noise coming from around the front (LH) cylinder bank. It goes from clacking to a louder occasional metallic whack at idle and above. Not completely constant at idle but in and out about 75 pct of the time. It seems to be at cam speed and not crank.

This is not a tappet noise but something more serious sounding. Engine has 100K and I am 2nd happy owner for 4 years now. I am picturing a broken keeper or bad spring,but really have no clue. Would this wreck the engine or could an on-car spring replacement be all I need?

Would a bent valve be a sure result in the case of a bad spring or broken keeper?

I think I could handle any on-car work. Local shop would need to take over if the service requires drivetrain removal. Will post a quick recording tomorrow and will have to pull the valve cover in a few days.

I suppose I am fortunate it's the easier to reach front bank :bigroll:

chubbyranger
04-05-08, 07:13 AM
I am living this dream on my 99 right now. Started with a tapping coming from somewhere around #5 on the rear bank. Turned into the cradle coming out yesterday because there is also the beginning of noise in the front. The beginning of my story is here:

http://www.cadillacforums.com/forums/cadillac-seville-cadillac-eldorado-forum/131216-99-sts-n-lifter-noise-advice.html

and continues here:

http://www.cadillacforums.com/forums/northstar-performance-technical-discussion/132305-pulling-camshaft-cover-can-done-w.html

and here:

http://www.cadillacforums.com/forums/northstar-performance-technical-discussion/132671-n-camshaft-removal-special-tools-required.html

The end has not been written yet.

Another thread on this topic here:
http://www.cadillacforums.com/forums/northstar-performance-technical-discussion/129524-northstar-valvetrain-clatter.html

I also posted a link to an audio recording of my car if you want some comparison: http://members.cox.net/chubbyranger/clatter.wav <-3.7MB file, not good for dial-up.

Good luck.

eisler99
04-06-08, 03:56 AM
Thanks for the links to your story on this, Chubbyranger and best of luck to you as well.

I was thinking about getting that chain tool myself. Or the kit if that's my ticket out of here. :hmm:

At first glance, it seems like the FSM tie-wrap cam gears/chain procedure would be good enough to maintain valve timing as long as the center sprocket end stays put. I am guessing that the hydraulic tensioner must be the roadblock down that easy street.

I had to laugh when you mentioned the wire stands.
I swear I broke a couple without even touching the damn things. :histeric:


I've yet to post an audio of my click and clack, yesterday's Wx around these parts was cool and very rainy.


Today is my better-half's birthday, so for now, just sharing a not so wee bit of the better things in life.

Not :tits:




Whisky. :)

chubbyranger
04-06-08, 09:27 AM
Not :tits:

Whisky. :)

1 out of 2 ain't bad :thumbsup: I have a bottle of Ardbeg and a good cigar waiting for the STS to come home.

eisler99
04-06-08, 09:14 PM
So it sounds like your car is getting professional help then. Good on ya as they say in the southern latitudes and here's to a happy toast upon return. ---Isle of Jura over here.


Looking to repair mine at home if possible. I am still looking for advice on what a lost keeper or bad spring would do to the combustion chamber and/or valve ?


Got under the hood for a quick recording today. Engine was cold and noise is louder and more regular than when it first appeared Friday.

93 STS Engine Noise - H e l p ! (http://www.snapdrive.net/qs/23337e64b8a2)

Oh, and in case anyone's wondering, with that kind of racket coming out of the engine, I did sideline the car. :eek:

Submariner409
04-06-08, 10:20 PM
Bent valve, lost keeper(s), broken spring: Not good due to probable valve-to-piston interference.
Collapsed hydraulic lash adjuster: laborious inconvenience.

eisler99
04-07-08, 06:09 PM
I'm all for laborious inconveniences, Submariner409 as long as I am the labor avoiding making a repair shop owners boat payment or five.

I will have to pull the valve covers to see clues are under there. So have you (or anyone) experience with a broken spring or failed keeper on this? Did the recording offer any clues?

chubbyranger
04-08-08, 12:39 AM
That really didn't sound good - but I can't tell if its recording quality or your engine exploding. The labor part on this can be extensive since the motor has to be lowered to remove the camshaft (valve) covers just to try to find the problems. A factory service manual is your best friend if you want to try any of this yourself. eBay or www.helminc.com are sources. I bit the bullet and sought professional help since its TFC (too cold) and I have no time to chase mine. Welcome to life's eternal compromise: doing it yourself or paying someone else to do it for you.

eisler99
04-08-08, 02:13 AM
My recording was from a cell phone and Q was a bit low. Once I get the cover off, I should know more. Need a puller for the water pump wheel.

Good advice on the manual. I've got the two blue books and according to them, the front bank cover comes off with no cradle jockeying. I can't imagine doing any on-car service to the RH head although the book's got a procedure.
I think they left out #11 - remove hood and #12 - sit Indian style on top cover. :eek:

chubbyranger
04-08-08, 07:52 PM
You can actually get the rear cover bolts out with a few new curse words and a sore back without dropping the motor - you just can't get it out of the engine bay. It gets stuck on the firewall and rear electrical harness. FSM says to remove the front two cradle bolts and lower it. Without a lift it started to get complicated. The front bank didn't seem to have much clearance around the radiator support either. That was the point I sought professional help. Only took 2 weeks to find somebody to work on it and a month for him to get it in. Last word I had was the engine is out and we're doing HGs and certs while its out :nono: