1.8T crank pulley damaged due to improper torque

[dougyfresh]

The four bolts that hold the serpentine belt pulley / harmonic balancer on the crank.... Replace them.

I just found out that my pulley has two of the four bolts on. The other two disappeared. No wonder my serpentine belt wobbles like mad and I thought the tensioner was bad.

Fuck. I think I've been driving like this since November.... A few thousand miles. SCARY

[A4natomical]

I didn't. I just used lock-tite. Time will tell.

When you put the motor back in, were you the one that tightened those four bolts?

[dougyfresh]

When you put the motor back in, were you the one that tightened those four bolts?

Yes, I was.

I've got bolts in my box of misc Audi/VW bolts so I'll use them with blue loc-tite until I can get a new set from the dealer. I hope the crank pulley and timing belt pulley are okay. Otherwise $$$$ for new ones.

[Raus]

I didn't. I just used lock-tite. Time will tell.

Me too last week...I really don't feel like going back in there again. I knew I was supposed to use new bolts too.

The proper tightening spec is 10Nm + 1/4 turn using loctite on the new bolts.

[A4ringedONE8T]

They arent a forged and/or stretch bolt so technically you can reuse them. I reused them, twice, with both of my builds and havent had a problem luckly

[absolutegtr]

I replaced them as well as the bolts used for the TB auto-tensioner. I believe I used loctite, but I did torque them to spec.

Atleast it wasnt the crank pulley bolt that was backing out

[dougyfresh]

The proper tightening spec is 10Nm + 1/4 turn using loctite on the new bolts.

Awesome! Thank You!

I was just about to ask for someone with a Bentley to find me the torque spec. I found four bolts in my 'box-o-parts'. Looks like the four bolts I took off the TT225 motor. Should work fine with some blue loc-tite and proper torque.

I'm heading over to my buddy's place this afternoon to get the car on the lift and pull the front end off and fix this 'ish. Thanks again!

[Wizard-of-OD]

Do not need to replace them....if you have to replace those then you need to replace your intake manifold bolts,oil filter housing bolts,etc etc etc

Just make sure they are on tight (no torque wrench needed there) and you are good to go.

[dougyfresh]

I'm fucked. The aluminum pulley (06B 105 243 F) is damaged really bad. I'll post pictures later tonight.


Jake told me the new part number is 06A 105 243 E. Is this true? I trust him but thought I'd ask you guys. The pulley I pulled off the 2001 TT225 motor I had is an 06A 105 243 E but its all steel whereas my '02 pulley is aluminum and steel. The plan is to send Jake the TT pulley so he can make sure its balanced. I'll then have it back on Thursday and can get the Avant back together so I can spend next weekend in northern Vermont snowboarding rather than wrenching on the Avant...

[317ssayzarc]

Doug, plug the original part # into the link below, you will see a 2nd source confirming

https://www.1stvwparts.com/part_number.html

[dougyfresh]

Doug, plug the original part # into the link below, you will see a 2nd source confirming

https://www.1stvwparts.com/part_number.html

Hmm. Do you have a cross-reference for Audi too? I know they are the same but I just want to confirm. I also know of the refutable sources who also told you this on the phone so I really am not worried about using the TT one. Esp after you check its balance.

[317ssayzarc]

Not sure Doug, lemme check

[317ssayzarc]

Nah man, can't find one

Audi part lookups are harder to find than VW, you could call the dealer tomorrow and they will tell you though

[A4 TSCHUSS]

I have had mine off and on like 4 times. I just zap them in with my Snap On 18volt impact driver. Always been good so far.

[Audi Skate Snow]

ive seen a few of them back out before, just not tight enough.

at least you caught it before anything bad happend

[dirtybrd]

I've never replace them on any timing belt jobs I've done. I just make sure they're good and tight.

[kwimberly]

I just make sure they're good and tight.

good to hear! j/k

chris can torque to 4,000 lb so he knows tight..

[dougyfresh]

Understood guys. Don't really have to replace the bolts when doing a timing belt. The only one I have replace bolts on to this day is Greg's (actlsub9) because he had new bolts.


In my situation, I have to replace the bolts and the crank pulley because I damaged them. Luckly the threads in the timing belt pulley are still perfectly good so I'm safe. MAJOR disaster on the relatively new motor averted.

This picture below was taken immediately after I pulled the core support off the car. Those two bolts are hand tight.


If my math is correct I drove all of December with the car in this condition. My trip to North Carolina included. This also may have manifested itself around the time the T25 flange gasket blew (right before Thanksgiving). So, an easy 2,000miles at a minimum.


Front to back vibration due to lack of torque on the bolts and, later, lack of bolts caused excessive rub/wear on the aluminum pulley. The timing belt pulley is in perfect shape. The timing belt is perfectly fine as well. Max depth of rub is around 1.5-2mm per my dial calipers.



This is entirely my fault. I did not use loc-tite on these previously used bolts (bare, dry threads) and did not torque them down properly. Good news is it is my engine not a customer of mines.




Jake. Check your email!

[F16HTON]

Doug, allthough most mechanics will not replace those bolts, Audi specs say they will be replaced when removed, this is the same for any bolt that has green paint on it.

When I have my motor replaced for oil sludge, I tossed the pully because the bolts had backed out.

I was very fortunate too, as i was in Germany and Tracee was driving the hell out of my car, she had blown a boost hose (silicone 90 behind the headlight) and stopped driving the car.

I cam home from Germany for spring break, went straigh to the garage and fixed the hose, fired up the car and did not evewn make it out of the driveway before the pully had tossed, two of the four bolts had sheared off and the other two were sitting on the driveway.

I had a hell of a time fixing the car too, the tensioner was also fucked too.

Fortunately for me, the boost hose had blown off because when the pully gets tossed, you ruin the risk of tossing the timing belt too, and we all know what that will do.

Torque spec is torque spec, howevwer if you tighten shit as tight as you can get it, 99.9% of the time, it will never fail.

[A4natomical]

Good save Doug, I'll keep an eye out for mine as well.

[AudiA4_20T]

Doug, the timing would still be in check if that thing sheared off, I would imagine the only harm that would be done is you not having your accessories

[Wizard-of-OD]

this is the same for any bolt that has green paint on it.

Greg the green paint is actually a coating.Before the bolts were either black oxide coated or zinc/cadmium plated.Now they are just plated/coated with green #6 zinc if I remember correctly.
Not every green bolt needs changing and the same goes for the OEM crankshaft accessory bolts.
As bad as this may sound for bolts holding manifolds,valve covers and other generic parts I usually do hand tight and I have not had 1 single failure over the 10+ years I have been doing this.You do not need to torque wrench every nut and bolt...

If you need a crankshaft pulley send me a PM.I have a whole bunch...

[illaudiill]

wow...that is scary

[lookaught]

wow! It's great that you found that before it fell off completely and bounced around in front of the motor. THis is why I use blue locktite on pretty much everything... what does it hurt?

I was in Hartford this weekend. Fantastic hike at the resevoir today in the snow with the dogs. HOly crap what a shitty flight home though, I just got back after leaving Hartford at 5. Im so jealous of the snow that you have had there this year.... in Pgh we don't get shite.

[Wizard-of-OD]

Problem solved :)

[Turbo1A4]

damn good thing you caught that before it turned into something bad

[dougyfresh]

Problem solved. The steel pulley I had in my stash-o-parts in my basement is correct so I do not have to buy a new one. That spare motor has saved me yet again . Glad I didn't throw anything out from it.

There is a steel and aluminum version. Funny, ETKA says the steel version is what should be in my car and the aluminum version is what should have been on my spare motor ('01 AMU motor). What I had was the exact opposite.

I sent the steel pulley out to Jake this morning and he is going to confirm that it is balanced properly (and will balance it if it is out). Thanks for your help; Jake, Issam and Greg!

I was in Hartford this weekend. Fantastic hike at the resevoir today in the snow with the dogs. HOly crap what a shitty flight home though, I just got back after leaving Hartford at 5. Im so jealous of the snow that you have had there this year.... in Pgh we don't get shite.

Too tired to go hiking yesterday. Wound up shoveling the driveway (with a sheet of ice underneath the snow), eating nice homemade pizza all afternoon and then finding this problem. Oh, and booking my airfare to Utah.