Klacking from the enigine

[SirSilvia]

Been away too long from NICO but been busier than IDK what. Moving and working lost my job and been hunting for a new one.

Recent work: replaced cat gasket for a bad exhaust leak.

So anyway, I was coming back from Pittsburgh from a job interview and I hear this noise which didn't seem to be an issue since I know I have a slight noise in the bay from after I replaced the timing chain guides and everything. Stopped to get gas and heard the sound louder idling. Couldn't see anything loose or out of place, double checked the fluids etc.

So I decided I might as well limp as far as I can to cut down the distance the tow truck would cost.
It just got worse from there, I was trying to dignose it while driving to see what it might be. I didn't feel any real noticeable loss in power or anything.

But I did notice something, while accelerating, it was fine and sounded "ok".
While decelerating, letting the engine/trans slow it down, it was fine and sounded "ok".
But in between accelerating to 2900 RPMs, where I was then going speed limit and let off the gas. It started this nerve grinding clacking. So I gassed it a little, going over 3500 RPMs to see if it would go away and it did, till the engine caught up with the load. Like I said decelerating sounded fine.

I figured I didn't want a mobile eruption of searing hot metal on the highway and pulled over. Got stuck 20 miles South of Evans City on I-79 waiting for a tow.




So in summary:
When the engine didn't have as much pressure in it, it was clacking. When it had greater pressure in it, then it sounded fine. I don't think the gasket I replaced did much of anything to cause it. It did however restore the back pressure that it was lacking for a while, which IDK if that was enough to cause any sort of harm.

Best guess:
-First thought it was a broken valve stem, but figured I'd blow something up by then and there would be a great deal of power loss probably.
-Brainstormed with a buddy and came up with it might be just a broken valve spring. since that would best describe the issue with the sound going away when there was more pressure and the clacking of it flopping up and down when less pressure was in the cylinder.


soo... any other ideas?

[CRyan]

Meh, I deal with this in my 93 Celica. Do you have anything to measure oil pressure? If so, get to reading. You may not be making enough pressure to get to all your feeds in the head.

Thats only my first guess, though. Does it sound like "valve chatter"?, or is it more so a clacking like something loose slapping something else?

That sounded dirty.

[SirSilvia]

It kinda bogs a little when it's making the noise, and I don't have anything to measure the oil pressure yet.

It seriously sounds horrid and haven't started it in about 3 weeks. I dare not till I at least crack open the valve cover to take a peek.

[breadbox]

Maybe time for an oil pump and a new pickup. My friend's was pretty caked up. and my spare motor had pine straw and crap gunking up the pickup.

[Dattebayo]

Your timing chain tensioner is probably malfunctioning. The tensioner is actuated by oil pressure. Remove the front cover and check it. I have a spare if you need one.

[SirSilvia]

ah man if it's that i'll be even more jacked. I just replaced all that and made sure the pump was primed the pump. Things replaced: both timing sprockets, chain, both guides, oil seal, front main seal, stat housing seal, oil pan seal, valve cover seal.

I should finally have some time this weekend to take a look.

:edit: and the tensioner

[Dattebayo]

Maybe you just need to clean out the hole that the oil pressure goes through to actuate the tensioner. I've heard from some that it gets clogged occasionally.

[SirSilvia]

Maybe you just need to clean out the hole that the oil pressure goes through to actuate the tensioner. I've heard from some that it gets clogged occasionally.

could be, I shreaded the old plastic guide at drift practice.

...didn't know it was made of plastic -insert the "more you know" pic-

[Yesitisi]

Small attack gnomes. Just throw some ground up Psilocybin in the gas tank...

You should be good.

[breadbox]

lol, no it turns them into demons. That only getting worse.

I will say that I noticed these specific things about my spare KAe.

Plastic chain guides can suck it.

Improperly fitting guide bolts and tensioner bolts will back out and just drop down into the oil pan, but not before fighting the lower chain sprocket.

I took off the oil pan of that motor and found the entire plastic chain guide chewed up and in pieces. Two chain guide bolts, flawless looking. One tensioner bolt that got F'd up hard. and a good amount of dirt and pine straw. When I took off the head, I just pulled the tensioner out. and the front cover had chain saw marks and a small crack into the water jacket, which i guess is all it takes.

Moral: Use OEM bolts. OR make sure those buggers fit great! Use the OEM metal guide with plastic plate not the ebay all plastic ones.

[SirSilvia]

I did, that's all taken care of now, we removed the oil pan and repaineted even after getting all the pieces out of it. I like that the new guide is made of metal and plastic, but something tells be that the plastic is gonna shear off in no time. Not that I'm too worried about it but w/e.

[breadbox]

I was thinking the same thing holding the bracket. but at least it has the metal bracket not all brittle plastic.

[SirSilvia]

yeah, today we'll see. I have to do a little yardwork and ship a package then will take a look inside

[Klits562]

why dont aftermarket timing chain kits come with metal guides? WHY!!!!!!!!!????????

[SirSilvia]

why dont aftermarket timing chain kits come with metal guides? WHY!!!!!!!!!????????

what? Where did I say that? Lol here's the kit I got.

[SirSilvia]

::in the above pic, the plastic/metal guide on the right did exactly what I though it would.
The plastic piece is gone, probably shredded off::

Popped the cover and looked, here's a vid http://www.youtube.com/watch?v=2yqveZks2GQ

Thought it was a broken valve spring, it wasn't.

Everything looks fine, nothing broken, no pieces strewn about, rockers look fine.

Chain and guide is fine, tensioner guide and tensioner is fine.

No oil in the rad so the hole that was welded in the coolant port of the timing cover held up.

I'm going to look in the spark plug holes tomorrow see if I can find anything. I have a small camera that should fit.

[Razi]

The plastic breaking off the guide was probably why you had that clacking noise.
Hopefully that's your only problem!

[SirSilvia]

omg I hope, but something tells me it's not. I'm talking the clacking sounded bad enough that I didn't want to start it again. Plastic would disintegrate if that's what I was hearing.

[SirSilvia]

void - double post

[SirSilvia]

well...
http://www.youtube.com/watch?v=YqKhn1sa ... tube_gdata
it runs but doesn't seem like it's gonna go far since it seems to wanna die if I gas it

[SirSilvia]

someone commented saying it sounds like rod knock.
-sadface time- looked around and this sounds pretty much like what i'm hearing.

Rod knocks are loudest at higher speeds (over 2500 RPM) Feathering the gas pedal may result in a distinctive back rattle between 2500 and 3500 RPMs.

[Lonismos14]

I'm sorry my friend it is rod knock. O well time for a de swap .