What cause that engine noise?

[megadan]

Since i'm new with DSM, I don't really know those engine. I just bought a 95 Talon tsi AWD and the engine is doing a knocking sound. If I rev it a bit (2500rpm) the sound does NOT stop as many post I read. The sound is just faster. I though it maybe was a valve but the compression is 165 150 165 150. I also found on the windshield a oil change "vignette" (dont know in english). On it it show 162000km and the car is 180000km. Could no oil change during that time could have cause this problem: carbon or valve lifter to go bad? Im so happy to have a new car but I dont want to nmake it worst or blow the engine.

WHAT COULD IT BE PLEASE!?!

thanks

 

[realhp=turbo]

Napa most likely has it but if you absolutly cant find it, try ordering it online. And yes, you could've gotten away with 0 damage to your valves but thats hard to say.
mike

 

[flytalon93]

Just to make sure everything is perfect for you, I would remove all accessories and ensure everything is up to snuff.

 

[megadan]

Ok guys update.

I removed the timing cover.... the balance shaft belt was broken .
Lucky that my timing belt has survive.

But the question is: Could a balance shaft not working could cause vibration and a tocking noise also no power impossible to go after 3000 rpm

At NAPA the freaking timing belt cost 150$ CAN and balance shaft belt 50$ pretty expensive.

 

[flytalon93]

Yes, if the belt is broken then the whole rotating mass is out of balance. I'm glad you found it. Make sure you buy the quality belts because you were lucky that the balance shaft belt didn't shred your timing belt. I guess the individual who did you timing belt job before, didn't really know what he was doing.

 

[megadan]

Now I woder why my belt is broken. Could it be possible that my balance shaft has seize.

am I suppose to be able to trun the balance shaft by hand.

Can I bypass the balance shaft.

 

[megadan]

For balance shaft bypass, is it the same way as for 1Gs

Do we have 2 balance shaft and if yes where is the sproket located

 

[megadan]

Ok I've decided to keep the balance shaft on and buy a balancer belt and a Timing belt. Today they are on but didn't have time to start the car.

Is it possible to make a mistake and bent valve if all pulley are align with their respective mark or do I have to check for piston #1 to be on top or something like that... I'm confused and dont want to do any mistake.

Thanks

 

[megadan]

Ok now I've started the engine and the tocking noise is still there. The engine seems to vibrate less however.

How to get rid of that noise!?!

 

[Defiant]

You probably have a failed balance shaft bearing.

 

[megadan]

But with the balancer belt off, I had the noise anyway.

 

[megadan]

I'm not arguing but just trying to put you on a track because I have no more clue and I want to drive the car so bad.

 

[Strm Trpr]

You have 2 balance shafts in your engine.
The front balance shaft is driven by the belt that you found broke.
The rear balance shaft is driven by the main timing belt that turns the oil pump sprocket.
Inside the oil pump are a couple of involute gears that create the oil pressure for your engine, and also drive the rear balance shaft.
The noise you are hearing is because the previous owner drove the car around with the front balance shaft belt broken which in turn thru the engine out of balance.
The balance shafts spin at almost twice the rpm as the engine. That noise you hear is the rear inner most bearing failing, and when it does,
you can forget about oil pressure and the rest of your engine. Do yourself a favor and remove both balance shafts by doing this procedure. <a href = http://www.vfaq.com/mods/balance-shafts.html>Balance Shaft Elimination</a>

Also, I hope you followed this:<a href = http://www.vfaq.com/mods/timingbelt-2G.html>2g Timing Belt Replacement</a>

 

[megadan]

I washed with gas all the lifter and when I started the car there was a "tick" sound. I know it is normal has there were empty but now I know what a lifter tick sound is.

My noise is more like a "tock" accompagned with a lost of power.

So my guess was a spun rod bearing and I was going to swap the motor as the spun bearing surely jerk the crank and need to unbolt the tranny to repair the crank.

Thanks for your post Strm Trpr. It gave me hope that maybe the swap will not be necessary. If it is a balance shaft bearing, you can be sure they will be thrown in garbage!!!

If you have any other info on what the car might have let me know.

Im learning a lot on the car by reading by how can tell it is a bad balance bearing once the oil pan is down?

 

[Strm Trpr]

If there is any significant damage, you'll more than likely find metal in the lowest portion of the oil pan.
This won't necessarily tell you it's a B-Shaft bearing, but at least you'll know if you have to tear the engine apart, or replace it.
Did you try to turn the front b-shaft sprocket with your hand?
Did it spin freely?
It should have.
Also, with your T-belt off, you can spin the oil pump sprocket with your hand, and that too should spin freely.
If it feels notchy at all, then more than likely your b-shafts are hurting your engine.
If both shafts spin freely with no hang ups, then your problems lie elsewhere.

 

[megadan]

Both could spin freely but for the oil pump one, I dont remember if it was notchy.

Dammit! I guess I'll have to desinstall the timing belt again.

Thanks for your help

 

[megadan]

It is weird tough because my sound seems coming from the head. My oncle keep saying it is coming from my valve but I've some good compression numbers.

 

[RyanTSi]

So my guess was a spun rod bearing and I was going to swap the motor as the spun bearing surely jerk the crank and need to unbolt the tranny to repair the crank.

QUOTE]

Just as a heads up, I just recently had to replace the connecting rod bearings on my
1g TSi and trust me dude, If you spun a rod bearing (at least in my case) it will sound a heck of a lot worse than a tock. But for future reference, and I wish I knew this beforehand, no swap necessary, pull the oil pan and rotate the crank till you can get to it. Good Luck Bud.

 

[megadan]

Ok now the pan is out and it is a connecting rod bearing.

I can move one with my hand. Is the bearing only a little metal plate? I know nothing to motors and I never opened one before today. I though it was ball bearings.

There is also a big frame (protector maybe) that seems to support the crank with 17mm bolt. There are bearing (metal plate) too and they are all scratch.

And the part on the crank where the connecting rod bearing is connected seems to be scratch too.

What to do next to repair all that.

Before repairing, do I have to find the cause of that or it is just normal wear.

I don't know what the past owner did to the car; maybe It missed oil.. I dunno.

 

[megadan]

I'll keep you updated till the end... even if it is not a good one

 

[megadan]

Now I've pinpoint the origin of the tock noise.

It was a completely missing upper connecting rod bearing.

So, to do a little summary:

MISSING A FREAKING BEARING IN THE THIRD CONNECTING ROD. SAINT-TABARNAK!!!

3 journals seems scratch and where the rod connect the crank.

Can I just replace all bearing with new and go!!!

 

[flytalon93]

You could replace the bearings but they will only probably last about 30mins or so. The scratches will eat the bearings up. You could get the shaft re-polished.

 

[Spyder FX]

It depends the extent of the damage really... For instance I'm getting a new shortblock because of spun rod bearings... Steve and I talked to Wes Hess about this and it's not a good idea to just replace the bearing and calling it good. Your damage sounds as bad as mine actually

 

[megadan]

At NAPA, a connecting rod bearing is 60$ CAN. Well I need for of them plus all main bearing plus a new crank or polish the old so I'am going to change the engine in the car.

Can I just put a 1G non turbo motor in it and take my 2g turbo to complete the swap?

 

[RyanTSi]

You said the connecting rod bearing was missing, are you sure its actually missing our did it spin, thats what happenend to mine. Fortunately My guides and journals werent scarred so i replaced all the connecting rod bearings, plastigauged it put it back together and called it good and it runs fine, othere than the problems you get with breaking in a reinstalled motor. Not calling you stupid, i just couldnt see my bearing when i pulled the journal off and i had to pull it out of the side of the guide on the copnnecting ro in with a scribe because it spun all the way around. Id try that, $60 CAN is a lot cheaper than a new motor, btw my car is a 93 tsi AWD.

 

[megadan]

As I am new with internal motor names (and i'm french)

Journal= Place where the main bearing sits on the crank?

Because It was missing a bearing on the Connecting rod and I looked with a flashlight and it wasn't there all the way around.

By the way, What is the cheapest place to order a crank on the net?

I heard of Roadrace Engineering, AMS, Slowboy, e-bay... any others?

Is replacing the crank a big challenge?
Because the oil pan is already off, transfert case too, downpipe, crank sproket (started the car with a breaker bar in the hole of the sproket by accident No problem to unscrew it now )

What is left to do?

Thanks guys your saving me a lot of time and helping me much