Engine Builders please read. Metal to metal tap.

[Nighthawk01]

ok this may be long,, im going to try to exspain what it's doing the best i can,, any opions on this noise would be a great help.

91, tsi fwd turbo, (6 bolt)
144k miles on engine.
the engine runs great,, pulls hard, no operating problems what so ever.
there is a "loud" taping when the engine is first started. when i say "loud" it is louder then your average hydrolic lifter tap.
to the best of my ability, it seems that it's coming from the top/drivers side, or possibly somewhere down in the area of the balancer's (far as i know the engine did not have the balance shafts removed)
here's where things get tricky.
when the engine speed is raised, the speed of the tapping or "metal to metal banging" increases. but once 2400 rpm is reached or higher. the noise is completly gone. untill the engine returns under 2400 rpm. never a different speed, always 2400 or higher when it goes away.
there is no Shaking, or any type of bad running conditions what so ever at any time with this.
here's more:
over time, and once the engine is warmed up, the noise decreases and after being driven for a long period of time will completly go away. untill the engine is cold again and then restarted.
i was thinking myself that this was a lifter bitting the dust.
however i have never worked on a vehical with a lifter this loud, or one that completly left at higher rpm's ect.
(i've worked on alot of cars)
i would be thankful for any input given!


Isaac

 

[Nighthawk01]

all this has gotten louder/longer to go away, recently.
didnt used to do it all as bad.

 

[Nighthawk01]

they are almost certant it's a colapsed lifter.
anyone put new lifters in one of these latly? long long am i looking at , and can it all be done with the motor in the car? (needs a new timing belt anyway )

 

[Max Speed]

I had a bad noise / knock and found it to be the out side of the flywheel the belt runs on had broke free from the flywheel (out side ring on flywheel the the belt runs on). It would still turn the belt but not real fast it would rattle and knock. At first it was tough to find, I had to change the main flywheel to fix it.. Very easy to do... check it out you may find this is the noise.

 

[Nighthawk01]

are you refering to the crank pully?

 

[Defiant]

Check the harmonic balancer.

 

[Max Speed]

yes your right crank pully... sorry ... called it the wrong thing (red faced here) that made me look dumb as a box of rocks.... aaaaaaaaaa well what can I say.. Anyway with the belt tension on it that made it hard to spot at first..

 

[Nighthawk01]

figured thats what ya ment
, did it wooble or make anything odd movment while running on yers?
it doesnt seem to be on mine,, im gonna get it in the air here soon and get the engine cover off and see if i can find anything wrong.
was it just bolted on loosly?

 

[Max Speed]

It did move around from side to side a very little (in to the timing cover and out to the frame) The belt for the most part kept it lined up and the rubber getting hot and sticking helped to keep it turning. It would slip and grab and made it sound very much like a rod knock.... I'm new to the EFI and computer stuff,,, This is the first smaller car I have had that has the potential to be a lot of fun. I do have a few neat toys. A 2000 Hayabusa, a Bandit 1200S (wife's cycle) and a 1970 Mach 1 Stang with a built Big block 475cid that runs 11.80 1/4 mile at New York Int. Dragway...
http://www.dsmtuners.com/forums/attachment.php?s=&postid=826728

 

[Nighthawk01]

ok tore into it a bit today after work,,
firstthing i checked was he harmonic balancer, which is in good shape.
pulled the upper timing belt cover and valve cover, i bout craped myself,,
the timing belt is LOOSE, you can grab the timing belt and move it all around in the sprockets.
if you grab the "front" sprocket, you can rotate it back and forth about the distance of a 1/3rd or 1/2 of a tooth. thats how loose the timing belt is,,
you however cannot move there rear (towards the back of the car) sprocket.
so im guessing the tensioner is maxed out and shot???
of course i am no longer driving or running the car.
untill i get the t-belt changed.

but do you guys think the tensioner is making this noise? thanx again guys.

P.S,, Defiant,, i used one of your ideas from another post (get 5 feet of vac hose and listen to where the noise is coming from ect.)
and it lead me right to the front/left (or ds) of the motor) right near the tensioner, so im guessing i have found the problem.

 

[Jason84]

its your timing belt....... just do a full timing belt balance belt and tensioner and all the pullys(bearings) job.

my car made a REALLY loud racket when i first bought it to... got the tbelt done and it was quiet as could be.

 

[Max Speed]

hope the valves did not make contact with the pistons, I do know that this is a non clearance motor. (If belt timing gets to far out of wack the valves will hit piston tops) I would do the timing belt and balance shaft belt then do a compression test.

 

[Nighthawk01]

Originally posted by Max Speed
hope the valves did not make contact with the pistons, I do know that this is a non clearance motor. (If belt timing gets to far out of wack the valves will hit piston tops) I would do the timing belt and balance shaft belt then do a compression test.

It is a "non clearance" or better known as an "Interference" motor.


Like i said,, the engine runs great (no longer running it till the t-belt job is done).

so it's douwtfull that any of the valves are damidged.