valvetrain knock

[rice_eater]

Well, this just isnt a good week for my car. I've recently been noticing a ticking coming from the engine, and its not the normal ticking at startup that goes away in a couple of minutes. It seems to tick under light-moderate throttle, or when the engine is dropping revs (think pushing in the clutch before a stop sign). Its not very loud at all, and i wouldnt even be able to hear it in the car if I wasnt listening for it. I found it by listening under the hood, I was actually checking for exhaust leaks. Anyway, I went over to my uncles house and we got out the big listening stick (old shovel handle, great for finding noises) and went to work tracking down the noise. We couldnt pin it down exactly, since its not an ever present thing, it comes and goes. But we coaxed it out of the engine enough to find it seems to be coming from the valvetrain, possibly cylinders 1 and 4, and it is quite noticeable on the exhaust side of the engine. That is, when we stuck the stick on the header tubes, we could hear it pretty loud and clear, it was much fainter/barely noticable on listening through the intake manifold or the valvecover itself.

Now, my question for you guys is, what would be the likely culprit, and is this something i could possibly fix with an oil additive or will i need to rip apart the top of the engine and replace things? The first thought that came to our minds was lifters. Are the lifters adjustable or not? I really hope this isnt something major, like worn cams.... or worse, worn valves. Please help me out here guys!

[HoodooGuru]

Get the tapets adjusted. Id say its that. Easy and quick to fix.
The tapets need adjusting quite often on older higher mileage engines. Nothin to worry about at all.

[rice_eater]

Ok, please bear with me here. As far as the valvetrain goes i have an IQ of like -5. I know the cam spins and the valves go up and down but my knowledge of the parts in between is quite limited. Could you explain to me what tapets are and how i go about adjusting them? Thanks a bunch for the reply Hoodoo.

[HoodooGuru]

Tappets ride on the camshaft and actuate the valves. On a flathead, they directly open the valves, on an overhead valve engine they push rocker arms via the push rods to perform the same function.

[rice_eater]

Are we talking about the lash adjusters or whatever they are called? How do i go about adjusting these tapets or whatever? What is involved as far as tools and what do i need to take off the engine? Can i just pull of the valve cover and get at them, or do i need to pull out the cams? Thanks for the info.

[rice_eater]

Alright guys, time for an update. Did some more listening diagnostics the other night, a reliable source with good ears tells me it sounds like something in the valvetrain above cylinder #2, either gummed lash adjusters (lifters) or sticky valves. I've talked to a few people and it doesnt sound like there is anything to manually adjust in the valvetrain. Maybe someone whose had a DOHC head apart could tell me for sure? (Radar, ACR98, TX???) I think I'm going to try adding some Marvels Mystery Oil and see if that helps. I just dont see how anything could be that gummed up, I've run Castrol Syntec since I got the car. You'd think if there was any gum or varnish sticking to parts I would've noticed the ticking when i first got the car, not a year later. Is there anyway I can check my oil pressure since I dont have a gauge?

Here's the basic low-down on my car right now:
2.0L DOHC; 111,700 miles; spiritedly driven, but NOT BEAT; 95% city driving, MANY short trips; Last oil change was last week (9months/3,000miles), switched from 10w30 Castrol Syntec (full synthetic) to 5w50 Castrol Syntec.

Will update after Marvels Mystery Oil is added.

IF ANYONE HAS ANY IDEA ABOUT WHAT IS UP WITH MY CAR, PLEASE HELP!!!!

[sleeperrt]

well Im going to put my 2 cents in here and say it might be from the oil change. you was running 10/30 now your running 5/50 and if im right (i might not) but that would mean you went to a leaner oil and with a high mile engine it might be too thin of oil, and now you have valve noise because the valve train is not getting enough lubrication.

[n-gin]

HMMM sounds like you havw your hands full with this.
Back to the exhaust, Check for any black soot around the head were the exhaust manifold meets the head if there is then you have a leaking exhaust manifold gasket. Some things that might help find a leak is partially restrict the exhaust with a rag or banana like in Beverlly hills cop LOL. The increased back presure will make the "tick" louder id=f it is due to a exhaust leak. Instead of using a handle try to use a 3/8 fuel hose, hold it up to your ear while you probe the engine compartment. Also check for broken off exhaust manifold bolts.
One question here is it more of a blunt tick or is it like a sharp tick??
Buy a quart of lucas engine treatment. It comes in a white bottle that looks like the bottle for rear end lube. It is really thick oil for hard running engines, $8 a quart but really good stuff. Drian one quart of oil out before putting this in. If it the tick goes away then it is internally in your engine. To my knoledge there is not adjustment on these engines for valve lash.
Good luck and happy wrenching.

[rice_eater]

Thanks for the reply n-gin. I thought exhaust leak as well at first, but after listening i'm nearly positive it is coming from the head, specifically the intake side (highest point in engine, keep in mind for later). Header just installed about 1000-1500 miles ago, new bolts, thick flange, dont think its leaking. It is a sharp metallic tick, not blunt at all. I tried adding a quart of Marvels Mystery Oil, but it didnt seem to do anything after putting 20 miles on (i know thats not enough to be sure, but i think i have a different problem, I'll explain below)

well Im going to put my 2 cents in here and say it might be from the oil change. you was running 10/30 now your running 5/50 and if im right (i might not) but that would mean you went to a leaner oil and with a high mile engine it might be too thin of oil, and now you have valve noise because the valve train is not getting enough lubrication.
I think it is from the oil change as well. However, just the opposite of what you suggest. 5w50 is thicker than 10w30 when the engine is warm. After doing some digging on the .org I ran across a thread describing how thicker oil is not always good, and in most cases bad, since the stock oil pump is not ment to push the higher weight oil. I think the higher weight oil is stressing the oil pump, lowering oil pressure just enough to produce a mild tick in the valvetrain. After all, you'd notice low oil pressure at the top of the engine first. (I really wish i had purchased the oil pressure gauge i planned on last fall...) The first clue was the tick started right after the oil change, the second clue was that it seems to get WORSE as the engine heats up (and oil weight changes from 5 to 50), instead of better. So tomorrow I will be draining $22 worth of two week old synthetic oil, to replace it with the correct weight. Man I feel stupid. Live and learn I guess, I hope I did not permanently damage the oil pump at all. I will post again to let you know if the correct oil solves the problem. (i sure hope it does)

[n-gin]

Before you do that just drain 1 quart and put the lucas oil treatment in.
I under stand what you are saying and yes it makes sense, BUT you have how many miles. Dont forget that the oil pump is powder metal which is stronger than aluminum and doesnt wear much, but they do wear. Get your self that oil gauge and a mounting pod for your pillar or steering column-you know you want too :thatfunny .
I work with the state and they have old and brand new cars wich require 5w20 oil,and guess what they all get 15w40. The new 2004 cars and mini vans allready have over 60,000, and the older ones have over 250,000. I know because I'm the one who takes care of them. Non absolutly non of them ever had engine failerues or tick or knocks.One of them did blew but that was operator error :) .
I'm sure what ever you do youll tell us. Good luck and happy wrenching.

[rice_eater]

Well, heres the scoop. Switched back to 5w30 and the tick seemed to dissapear. then it was back but so faint i could only hear it with the hood up and my ear next to the engine. Then it seemed to come back almost as noticable as it first was, but still quieter than just recently with the 5w50 (got slightly louder over time with the 5w50 oil).

But here is the kicker. took my car out for a drive today, pulled over and put it in neutral. Then i proceeded to slowly rev the engine, eventually taking it all the way up to the revlimiter. It sounded awesome above 3000, just like it should (a little vibration, but nothing not normal). when i came back down from 7200rpm, THE TICK WAS GONE!!!!!!!!!!! didnt come back the entire time the engine was running, i even tried to bring it out! Then i shut the car down at a friends house, and when i started it back up the tick was back.

Is this a coincidence? I'm baffled. The only conclusions i can think of are: 1) the tick is actually a mild exhaust leak and slow rev to redline generated enought exhaust heat to seal it momentarily (flange expanded). or 2) the revving it to 7000 wouldve increase oil pressure, meaning the ticking is due to slightly low oil pressure? but that doesnt explain why the tick was still gone 10 minutes after i had revved it up. I plan to look for exhaust leaks this evening. Maybe i'm just way too anal about little noises, LOL. If anyone has any ideas let me know.