Squirrels under my hood

[flier32]

Anytown,

Maybe I’ve overlooked your posts but what is your oil pressure?

 

[AnytownUSA]

Flier: My pressure is good, it's hard to tell on the analog gauge but I would guess between 45 and 48 psi. It has always, for the year I've had it, been in that range.

I think it is definitely valves chattering. It is not happening on the way home from work but first thing in the morning I hear it until the engine really begins to breathe and hence drowns out the clicking. Evidently the engine getting really cold over night aggravates it. Well, really cold for north Georgia anyway. It also does do it under relatively heavy throttle - 70 to 80%. Maybe it's finally time to get the little Mercury going again and work on the vette before I tear something up. Or…maybe I'll just try changing the oil first and let the Capri sit for another weekend!

Seriously, I would like to figure out what is wrong so I can fix it. I have not had a car in a mechanic's shop since early in college. I went in for an alignment and came out with about $400 in brake work it turned out I didn't need. You guys are a huge help. I know if you don't get tired of me chasing information, we'll figure this out.

 

[trackitman]

Update?

Anytown -

Still around? I was reading your posts tonight with keen interest. My '92 seems to have the same problem - noisey, tapping valvetrain. I am thinking lifters or valves. Wondering what you came up with for a solution. I have 58K miles on the car.

 

[AnytownUSA]

Yup I'm still here trackitman. I have not yet eliminated this ticking. I am going to try reseting the vavle lash like Zektor suggested, if that doesn't do it I'd like to go to rollers. Buuuuut, I haven't quite worked up the courage to open those covers yet. I found a little oil seepage at the top of both vavle covers, which I figure is from the VC gaskets so I'll have to that and might as well hit the lifters at the same time.

I have been putting it off because I haven't gotten my backup ride together yet. I don't know how straightforward the lash adjustment will be, but just in case I'll need a way to work. The ticking is not any worse or better, the exhaust is clean, gas mileage is great, and no codes are showing up. I assume I'm not hurting anything - but my dad always said "when you assume you make an *ss out of u and me." I maybe sorry later.

I was not able to get any information on the fuel system/engine cleaner but the Chevy house guy I spoke with did not seem too bright. It took three trips over there to get the correct AC head unit replaced in my wife's car and it's a 2001 Malibu. I have been meaning to go by and speak to someone else about it but just haven't done it yet.

 

[trackitman]

Anytown -

I recently pulled off the valve covers, and adjusted the rockers. I used a clean long funnel as a hearing aid, with the wide portion close to my ear, and the narrow end to hone in on each rocker.

I found through this process that the tapping is originating where the rocker and the top of the valve meet. I backed off the mounting nut to the point where it was really tapping, then tightened until silent, then 1/2 turn. The tapping continued. I tried tightening it further, up to one complete turn, and the tapping continued. So, my theory is the tapping is a result of a worn lifter, or perhaps a worn rocker/valve stem.

I plan on running it the complete summer without doing anything further. Let me know if you discover anything different. My best guess is lifters.

 

[hawaii-5-lo]

hey there,
does the ticking increase with the rpms?the pushrods are the sacrifical components in the vavle train.you could have a or a few bent.this will be more than a little ticking,if you shut the hood and stand a few feet back,can you still hear it?is your car down on power?has the coolant temps risen for no apparent reason?if you think it is more than the injectors you probably should stop driving,or you may find the problem the hard way,which will cause other problems most likely.a long shot here but you never know,check you belt,belt tensioner and maybe stick a stethascope or a long screw on the water pump bearing(safely)when its cold and listen.good luck,Todd.

 

[trackitman]

Todd -

I confirmed the tapping sound originates where the rocker and the top of the valve meet. The noise is not coming from where the pushrod meets the rocker. I adjusted the rockers with the valve covers off, using the long funnel as a hearing amplifier. I was able to place the narrow end of the funnel right up next to the meeting place of the rocker and at the top of the valve. The wide end was placed next to my ear. You can hear an amplified sound from a very specific, targeted area this way.

Using this method, I determined two noisey rockers on both banks, tapping the valve stems.

Yes, the tapping increases with the RPM's.

Bent pushrod's could be a possibility, good thought.

I can hear the tapping with the valve covers on and the hood closed, from a few feet away, yes.

No power loss or cooling issues, just trying to quiet down the valvetrain. Kind of noisey.

Injectors are quiet.

Belt is in good shape.

Replaced the tensioner last year. It sounded like a supercharger whining down the street.

I don't have other noises around the water pump area, so I'm not concerned there.

Thanks for your ideas.

Trackitman

 

[hawaii-5-lo]

hey trackitman,
sounds like you have it pretty well checked out there,i think if a lifter was collaped,you would be down on power.you are probably right,its rockers,or push rods.funny,last night at the track,my buddy was shifting from 3rd to 4th but found second instead,rearend skidded,hit rev-limiter hard,after he got home he called me,he said theres a loud clicking noise.if you stand a couple feet away with hood shut,you can tell its not the injectors.its pretty loud clacking.(its an LS1)so took off the valve covers,4 intake side push-rods visably bent,will change them all on monday,lucky it wasnt more serious.anyway good luck,Todd.