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-   -   Top end clatter / lifter tick? (http://zr1.net/forum/showthread.php?t=24725)

cmb 02-28-2015 06:57 PM

Top end clatter / lifter tick?
 
Hi all,

I'm a new owner of a stock '95 car with 26K miles. I took delivery in early January, and I've tried to start and run the car every few weeks to circulate fluids, etc.

The last time I started it, I noticed a loud tick from under the passenger's side cam cover, toward the front of the engine. It's definitely a mechanical sound, i.e. not a noisy injector or exhaust leak. It seems to match cam timing, as the noise occurs about 5 times/sec at idle. Oil pressure has always been fine. There are no alarming sounds from any other part of the engine. I changed the oil and filter and have let the engine run until it's warm, but the noise persists.

For what it's worth, the car is in an unheated garage, and we have had some very cold nights here in New England.

Here's some cell phone video of the problem - pardon the rotated video, but the audio is the main point:
https://drive.google.com/file/d/0B83...ew?usp=sharing
(Note that you can still hear it when the camera is on the LH side of the engine, but that's only because the noise is loud enough to always be audible in the background.)

Any ideas on how I should approach this? I'm preparing myself for the possibility that I'll need to remove the cams on that side to replace the lifters. Is there anything else that I should try before this?

Assuming that I do need to replace lifters, can this be done with the engine in the car?

--Colin

KILLSHOTS 02-28-2015 07:23 PM

Re: Top end clatter / lifter tick?
 
Does it tick more quickly when you rev the engine? Seems like sort of a silly question but if it's something external, maybe the tick speed and engine speed would be unrelated? Figured it couldn't hurt to ask since you didn't mention it.

efnfast 02-28-2015 07:47 PM

Re: Top end clatter / lifter tick?
 
Dual mass flywheel? Or lack there of? Where in NH are you?

LGAFF 02-28-2015 07:50 PM

Re: Top end clatter / lifter tick?
 
Check for exhaust leaks....I have a ticking lifter, but not that loud. Does it idle smooth? Dual Mass Flywheel? belt tensioner?

Jagdpanzer 02-28-2015 08:31 PM

Re: Top end clatter / lifter tick?
 
Video sounds nasty.
You might try slacking the belt tensioner with the engine running to see if it makes any difference.

cmb 02-28-2015 08:55 PM

Re: Top end clatter / lifter tick?
 
Yes, the tick follows the engine speed. It will increase in rate if I bring the revs up past idle. The idle is smooth. Engine never stumbles, and doesn't sound like it's missing.

A couple of you have asked about the flywheel. How might this contribute to the noise? I don't have any particular reason to believe that it's ever been replaced -- does that mean it's the dual-mass part?

It's difficult to tell from the video, but the sound certainly seems to come from under the cam cover (at cyl #2) rather than from something external at the front of the engine.

I'll check out the belt tensioner. Is the thought that the tensioner itself might be bad, or that the belt tension is causing some other problem?

I'm in Merrimack, NH.

XfireZ51 02-28-2015 09:06 PM

Re: Top end clatter / lifter tick?
 
Throw some Marvel Mystery oil into oil. Let it run through. See if lifter quiets down.

We Gone 02-28-2015 09:09 PM

Re: Top end clatter / lifter tick?
 
Lifter or maybe a bad valve spring?

KILLSHOTS 02-28-2015 09:31 PM

Re: Top end clatter / lifter tick?
 
Quote:

Originally Posted by cmb (Post 220927)
Yes, the tick follows the engine speed. It will increase in rate if I bring the revs up past idle. The idle is smooth. Engine never stumbles, and doesn't sound like it's missing.

A couple of you have asked about the flywheel. How might this contribute to the noise? I don't have any particular reason to believe that it's ever been replaced -- does that mean it's the dual-mass part?

It's difficult to tell from the video, but the sound certainly seems to come from under the cam cover (at cyl #2) rather than from something external at the front of the engine.

I'll check out the belt tensioner. Is the thought that the tensioner itself might be bad, or that the belt tension is causing some other problem?

I'm in Merrimack, NH.

When I bought my car, it had bad injectors, which caused a misfire and a slightly rough idle, which in turn caused the dual mass flywheel to rattle...all very common on early cars which still have the original injectors. It sounded like a rod knock or a spun main bearing. That rattle was completely inconsistent with engine speed; revving it a bit made the rattle stop. From both the sound I hear in your video and your description, I'd say there's no chance that it's the DMF.

KILLSHOTS 02-28-2015 09:35 PM

Re: Top end clatter / lifter tick?
 
Also, that is not the belt tensioner. Mine was bad and I had Marc rebuild it. It does not tick like that...mine made a high-pitched whining/squealing sound.


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