UNKNOWN tapping (with Video)

[digeronimo34]

Ok here is what happened. In December i heard a knock on the way to work, this was durring the worst snow storm that we had up here last year. I stoped and called a tow truck but none were avalible due to the storm. I drove it home at about 30 mph for 38 miles. If i did not get above 4 grand in any gear you could not here it. I parked it and was not able to get to it for a few weeks after the storm.
Andrew came over and listened to it and we concluded that it was a chain tentioner. I pulled the intake and valve covers and sure enough the chains had eaten threw the tentioner and there was a lot of play in the chains. I got a set from a member on the forum and started to slowly order other parts that i was going to change wile i had it apart.
i painted the intake and valve covers and got the last of the parts. last week we started to put things back together. (Andrew, Hamal, Fonze and me)
These are the parts that we changed:
timing chain Tensioners
valve cover gaskets
cam seals
Valve Cover Bolt Grommets
re shimmed intake and exhaust cams to factory specks
timing belt
MTX Timing Belt Tensioner
water pump
cps
starter
battery cables
battery
dp plugs
spark plug wires
intake couplers hoses
silicone vacuum lines
intake gaskets
throtle body gasket
water pump


When we got finished it was like one in the morning. We started it up for a min without the acc belts just to see if every thing was ok. It started fine and seemed ok we shut it down for the night.
The next day i finished up, put the belt tentioners and belts back on and fired it back up so it could run for a wile, it had been 6 mounts since it was running.
Now i am having this knock that comes and goes it. I called andrew to see what he thought since we did not hear it that night.
We pulled the intake and valve covers back off and checked that we had done everything correctly and that every thing was tightened to speck. Every thing looked good.. I turned the engine over by had a couple of times and put it back together.
Still the same problem.
Here is what it sounds like.

[YOUTUBE]<object width="425" height="344"><param name="movie" value="http://www.youtube.com/v/z6nnr0kZHbA?hl=en&fs=1"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/z6nnr0kZHbA?hl=en&fs=1" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="425" height="344"></embed></object>[/YOUTUBE]

[YOUTUBE]<object style="height: 390px; width: 640px"><param name="movie" value="http://www.youtube.com/v/z6nnr0kZHbA?version=3"><param name="allowFullScreen" value="true"><param name="allowScriptAccess" value="always"><embed src="http://www.youtube.com/v/z6nnr0kZHbA?version=3" type="application/x-shockwave-flash" allowfullscreen="true" allowScriptAccess="always" width="640" height="390"></object>[/YOUTUBE]
The first one is short and the second video is about two min.
As the car gets to operating temp it becomes more frequent.

What do you think it is?

Here are the links if i did that wrong
http://www.youtube.com/watch?v=z6nnr0kZHbA
http://www.youtube.com/watch?v=ZACBbRO8gYM

 

[Bob Gervais]

A few things come to mind. A valve shim partially ejected or not fully seated, rod bearings (because it gets worse as the car gets to operating temp), accessories/tensioners (because it seems, from your description, that it didn't make this noise without the belts on).

I'd start by taking the accessory belts off and see if the noise is still there.

 

[digeronimo34]

Hey bob. It does the same with the belts on or off. When we first started it it was for only a min or less. Yesterday we tried it with them on and off and rechecked the caps and shim gap.

 

[Bob Gervais]

When you rechecked the shims, did you happen to look at the underside of the valve covers? Perhaps you got a bad chain tensioner that's allowing slack and causing the chain to hit the valve cover?

Other things that come to mind, off the top of my head: Timing belt sprockets tight? Crank bolt tight?

Any oil light flickering at idle? Possible to get a temporary oil pressure gauge on the engine to confirm oil pressure?

 

[digeronimo34]

Yep looked at the underside of the covers no marks, replaced tensioners crank bolt tightened to 125fl lb timing sprockets tight and no oil light . I'll get a tool for the oil presure . What do you think about the chains being streached ?

 

[FREAK_SHO]

Check the tension on the timing belt. Sounds like the belt is slapping around a bit.

 

[Bob Gervais]

Yep looked at the underside of the covers no marks, replaced tensioners crank bolt tightened to 125fl lb timing sprockets tight and no oil light . I'll get a tool for the oil presure . What do you think about the chains being streached ?

Crank bolt should be tighter than 125. I don't think that's your issue, just for reference.

I suppose it is possible for the chains to stretch, however I haven't had any experience with them stretching enough to cause this. Perhaps someone else with more knowledge will chime in... I hope!

 

[Racer X]

JR, did you guys follow the timing belt retensioning steps after I left? Rotate crank twice, line up the 2nd line or something and torque the tensioner bolt down to 40ft.lbs.?

I left before the crank pulley was back on, and couldn't do that step. And I'm almost certain that I didn't tension the timing tensioner to 40ft.lbs.

Sorry, thought you guys realized that.

 

[Bob Gervais]

ABM strikes again.

 

[Racer X]

ABM strikes again.

What's this again shit? :angelnot:

 

[Bob Gervais]

What's this again shit? :angelnot:

It's because I'm white, isn't it?

 

[Racer X]

It's because I'm white, isn't it?

I'm not even mad. Angry. Mad.

What were we talking about again?

 

[Bob Gervais]

SHOboom. I think.

 

[iKevin]

I have this same problem it just started today.

 

[digeronimo34]

JR, did you guys follow the timing belt retensioning steps after I left? Rotate crank twice, line up the 2nd line or something and torque the tensioner bolt down to 40ft.lbs.?

I left before the crank pulley was back on, and couldn't do that step. And I'm almost certain that I didn't tension the timing tensioner to 40ft.lbs.

Sorry, thought you guys realized that.

Nope we did not . I will when I get back home. andrew thinks that it sounds like its coming from the front valve cover idk

 

[Racer X]

SHOboom. I think.

Well this car came from Nick, so anything is possible. Though I think we've found and sorted out all of this car's Easter eggs. Or determined that the untouched Easter eggs weren't going to cause any further damage.

 

[digeronimo34]

I do have the top timing cover off don't see any unnatural movement same with the crank pulley

 

[FREAK_SHO]

You may not see any (unnatural) movement across the top of gears. I would re-tension the timing belt and re-torque the tensioner pulley bolt. Not going to hurt anything to do this.

 

[ShadetreeSHOguy]

(Applicable this time)




Crank Cancer......

 

[SHOspazz92]

You may not see any (unnatural) movement across the top of gears. I would re-tension the timing belt and re-torque the tensioner pulley bolt. Not going to hurt anything to do this.

This,

Especially because it was stated that it had not been done.

-Sam