The engine (350, RPM cam, TFS TW heads, Aluminum Roller rockers) developed a single valve tick over the course of this summer. A week ago I pulled a valve cover and adjusted the offending rocker tighter w/the engine running, until the tick ceased, then tightened the lock allen and put the valve cover back on.

I've driven it about 200 miles and the tick it re-emerging in good form; it's almost as loud now as it was in the first place (darn loud!)

I think the cam might be loosing a lobe. Am I over looking anything else?

-Tom

 

Pushrod loosing a tip, rocker loosing a cup or folcrum or roller.

What type/brand of aluminum rockers are they? Proform?

 

Hmm. A few good points there. I'll check... I saw the push rod and I think it's fine, but I didn't pull the rocker and check the cup. That's a good call, so thanks.

I don't know what kind of rockers they are; they were on the car when I bought it. They look like these Crane's kind of but they're more tapered on the top sides and on teh push rod end, rather than being squared off, they're tapered there too.

http://static.summitracing.com/globa...11747-16_w.jpg

-Tom

 

If the cam's going down so bad you are getting a recurring tick it's already lost a lot of it's lift. You can yank the valve cover and crank the engine over a few times on the starter. If the lobe on that valve is going down it will be OBVIOUS. The rocker arm on that valve will barely move compared to the others on either side of it. You can see it by eye- doesn't require any special tools or a dial gague. It's a very noticable difference.

 

I have the same RPM cam and roker arms with the same problem. I only have 200 miles on it and it is ticking bad. I thought it might be a dirty lifter and I am hoping it is not a bad cam lobe. What did you find out?

 

I agree. When I had the valve cover off last week, I looked for that specifically and at the time, I couldn't see any difference visually than the other valve's movement, but I'll check again when I pull the cover off again here tonight or tomorrow night after work.

So far this is "going" just like when I lost a lobe on a Comp XE cam about 10 years ago; adjust once, noise comes back....adjust again, noise comes back...adjust again noise comes back and it starts missing. Only I'm on the first "niose comes back" so far.

-Tom

 

How can I tell which rocker arm to adjust. I tried to listen but it is not as load with the rocker arms off. I did them all again staticly and they were tight. I have a bad feeling about this. Thanks Bill

 

Use a long screw driver or a long extension. W/the motor running, place one end of the tool on the rocker stud, and the other end under you ear agains your skull. The offending rocker will make WAY more noise than all the others.

-Tom

 

I will try it tonight. Thanks! How long do you think I have before the cam is gone???????

 

If the cam is wiping a lobe, I'd say less than 200 miles.

 

If it's wiping a lobe then it's already gone. The question then becomes what happened to all the metal that used to be part of the lobe and lifter?

 

The last time this happened to me, it took about 200 miles, or about two weeks to wipe the lobe to the point where it begain to miss.

There is a point at which it 'starts' and when it is "wiped".

 

Not to me, anyway. If its losing lift due to wear, then the cam and lifter are already dead, there's no saving them. Requiescat in pace, amen. There are metal shavings frolicking inside the engine doing who knows what.

 

The cam lobe is still lifting the rocker enough so that I cannot tell if it is bad and I also cannot here the loud lifter with the valve cover off. I tried a hose and the screw driver to here and feel but I could not hone in on the bad lifter. I may still have just a dirty lifter this is a work in progress.

 

No disrespect but is there a chance either of your problems is a ticking injector? if injected of course.

 

Mine has a POS Edelbrock 1411 (for the moment).

Plus, I verified the noisey rocker, tightened it which eliminated the noise, but now the noise is back.

Since Bgoetsc can't find a noisey lifter, maybe that's his issue? -Again if injected.

 

The rocker isn't hitting the valve cover is it?

 

I looked at the valve cover and there is no marks on it . I have tall valve covers. Why would it be just one rocker??? I will try it reversed it is wirth a try.

 

That is possible but you would think it would have eaten a hole in the VC by now. It only took 10 minutes to destroy one of my VC's and the chorme ones are supposed to be universal.

 

Maybe the lock nut on the rocker is coming lose? Or you have a lifter going bad.

 

It was a dirty lifter!!!! I cleared it by rapping hard twice with a piece of wood and a hammer on the rocker at the place were the push rod is. That forces the junk out of the lifter. Thanks for evetyones help. Bill

 

Hmmm, good to hear you "fixed" it. I'd still wonder about what was in it that caused it to stick, and where'd it go?

Hope that's the end of your problems!

 

It makes sense a week back I removed my intake manifold and replced the gaskets for an oil leak. I had to scrape off the old gasket. I thought i was carefull but a small piece of something got in there.

 

You can also take them apart to clean them.

 

That would be the logical thing to do. Lets just hit it w/ a hammer instead!

 

See this link! Whats the dif. If it was bad I would have had to replace the whole thing anyway!!!

http://www.buicks.net/shop/reference...e_lifters.html

Noisy Valve Lifters
When checking hydraulic valve lifters, remember that grit, sludge, varnish or other foreign matter will seriously affect operation of these lifters. If any foreign substance is found in the lifters or engine where it may be circulated by the lubrication system, a thorough cleaning job must be done to avoid a repetition of lifter trouble.
To help prevent lifter trouble, the engine oil and oil filter must be changed as recommended in the service manual. The engine oil must be heavy-duty type (MS marked on container) and must also conform to GM Specification 6041-M to avoid detrimental formation of sludge and varnish. A car owner should be specifically advised of these requirements when the car is delivered. Faulty valve lifter operation usually appears under one of the following conditions:

Rapping noise only when the engine is started. When engine is stopped, any lifter on a camshaft lobe is under pressure of the valve spring; therefore, leak down or escape of oil from the lower chamber can occur. When the engine is started a few seconds may be required to fill the lifter, particularly in cold weather. If noise occurs only occasionally, it may be considered normal requiring no correction. If noise occurs daily, however, check for (a) oil too heavy for prevailing temperatures, (b) excessive varnish in lifter.
Intermittent Rapping Noise. An intermittent rapping noise that appears and disappears every few seconds indicates leakage at check ball seat due to foreign particles, varnish, or defective surface of check ball or seat. Recondition, clean, and/or replace lifters as necessary.
Noise at idle and low speed. If one or more valve lifters are noisy on idle at up to approximately 25 mph but quiet at higher speeds, it indicates excessive leak down or faulty check ball seat on plunger. With engine idling, lifters with excessive leak down rate may be spotted by pressing down on each rocker arm above the push rod with equal pressure. Recondition or replace noisy lifters.
Generally noisy at all speeds. Check for high oil level in crankcase. See subparagraph (1) above. With engine idling, strike each rocker arm above push rod several sharp blows with a mallet; if noise disappears, it indicates that foreign material was keeping check ball from seating. Stop engine and place lifters on camshaft base circle. If there is lash clearance in any valve train, it indicates a stuck lifter plunger, worn lifter body lower end, or worn camshaft lobe.
Loud noise at normal operating temperature only. If a lifter develops a loud noise when engine is at normal operating temperature, but is quiet when engine is below normal temperature, it indicates an excessively fast leak down rate or scored lifter plunger. Recondition or replace lifter.

 

You meant sledge hammer right?

One last resort before digging into the engine of my 85 was Risol. You just pour it in the oil and let it idle for 10 minutes. I did it, changed the oil and I'll be dammed but it cured the sticky lifter. I was happier than a pig in shat!

 

I FINALLY got around to checking the above. (been traveling a ton)

No caved in rocker cups, no bad fulcrum bearings, and no broken pushrods.

I re-assembled everything, set the lash 1/2 turn, and it's still ticking the same as ever.

I also noticed another issue;
The number 8 exhaust push rod seems to be too long. It sticks up past the pushrod guide plate about 1". I pulled the rocker off #2 exhaust and it was sticking up about 1/2". Both push rods are exactly the same lenth. (?) WTF?

-Tom

 

Here are the Rockers. Anyone know what kind they are? They're about 12 years old. The one I'm pointing at is the noisy one.

 

No Broken Pushrods...

 

No caved in rockers...

 

Now onto the Cyl #8 "too long pushrod" issue...

Notice the orientation of the "locking allen" in the nut on #8 compared to the other tow in the pic...

 

Cylinder #2 Exhaust. This one is "correct"...or at least like the other 7...

 

Number 8. A whole 1/2" higher...

 

The pushrods are not different lenghts. Notice the wear marks from the guide plates though. (?) The rod on the top is the #8 one, the bottom is from #2...

 

Were the #2 and #8 pushrod pictures both taken on the base circle?

 

Yes. On the base circle. I knew I'd get asked that question.

Both on the base cirlce for the pics.

It's like the #8 exhaust lifter is too tall. (?)

Any ID of the rockers?

Also keep in mind that #8 Exh isn't the one making the noise. I just noticed the set screw orientation so I started investigating while I was in there. The noisy one is #6 Intake, as seen in the pic w/me pointing.

-Tom

 

Anyone? Any ideas on the tick, the rocker brand, or the too-tall lifter?

 

Are the rocker mounting studs all the same length?

 

They appear to be, yes.

If you notice the markings on the two pushrods, you can clearly see that the number 8 (top one) is getting marked further down on it's shaft than the #2 I used for comparisons. That means the pushrod itself is higher up. Plus my measurement of the two in teh above pics. So the stud hight si kind of irrelivent; the push rod is just too high.

Plus, when it's all together and you look down the row of rockers you can clearly see the #8 exh rocker is clearly higher up, or further away form the head than all the other exhaust rockers. This makes the rocker tilt much further forward to reach the valve. All I can think of is that the #8 exh lifter is taller, but that really makes no sense.

-Tom

 

It does if the lifters came in individual boxes when they were replaced.

Someone could have either could have either mis-boxed one or some cretin swapped the wrong one into the box. You wouldn't be the first one to report that on here.....

 

I've actually had one case where they were shrink wrapped in groups of 4 individual boxes and one box had the wrong part number inside a correctly marked box.

 

Huh. Well, I guess in order to get to the bottom of this, I'll need to pull the intake. I thought all SBC lifters were the same height (or close to it) since they all GENERALLY use the same lenght pushrod. This one is a solid 1/2" taller.

 

Yep, Im suprised you havent pulled the intake already.

That is just wrong.

 

Just thought of one other thing I did one time that can cause what you're seeing --- any chance the rocker nut on the "long" valve is turned upside down? In other words, flat side down instead of up for the nut to rest against? I ruined a nut that way one time where it ate up the center post and it was sitting higher than the rest....

 

Huh? what is "just wrong", that I haven't pulled the intake?

I have many other interests that consume my time besides 3rdgens. I just got back from two weeks vacation in Maine and then water skiing at LaHonton Reservoir in NV with Glen Plake. So there's two weeks that I haven't been around to touch the car. And so it goes... The car is low on the priority list -it's a hobby/sunny Sunday car, and it actually runs perfectly fine.

VERNW, Great thought about the upside down fulcrum, but I thought about that before I took it apart and that was the first thing I checked when I pulled it off. And it was on correctly. Again if the problem were w/the rocker or the stud the wear marks on the push rods would be in the same relative place. The push rod is just too high.

Also, I'm still looking for ideas on the #6 intake that is ticking, and the brand of rockers I've got here. Thanks for all the input though.

-Tom

 

No, I meant the pictures you posted.


That #8 lifter, if you put a push rod back in it do you feel any give (lash)? It's possible the lifter is different but you would think the person who assembled this engine would have noticed.

 

Gotcha. No, when I put the push rod in and tighten the rocker down peroperly, there is no lash. Is that what you were talking about?

Has anyone ever seen these rocker arms? Brand?

-Tom

 

Well the cam wasn't "wiping a lobe", cause it continued to run great, and I've now sold the car. The new owner drove it about 2000+ miles to it's new home (achieving OVER 22mpg), and there were no valve related issues. I still can't believe I never figured out:

*The #6 tick
*The #8 wacky geometry
*The BRAND OF ROCKERS! I mean...has no one on here seen these before??

Oh well. That chapter in my car-life history is now closed. On to a Corvette....

-Tom

 

Always makes me want to cry when someone sells their third gen, I know I would if I sold mine....