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Mokeylock
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Discussion Starter · #1 ·
A year ago my Engine Transmission Mount broke because I loosened one of the two bolts and messed the thread up when putting it back together (no comments please [:p]). I then changed it to another OEM part but this summer the Engine Lower Pendulum Mount broke; one of the bolts broke off (not my fault this time.. just hard driving i guess!). I decided then to change all 3 mounts to the VF Engineering ones... they're beautiful, no complaints.

My question is, when the mounts broke both time, I didn't really get the engine/gearbox checked because I didn't know what parts of it might of gotten damaged. I'm glad to say that it seems like there's no damage since it's been ok till now but there's a weird vibration that's appeared recently. The car was at VW this weekend and they said it could be the flywheel mis-alligned. Could this have been caused when the mounts broke and the engine dropped to the side? what else could have happened that I should look into.

I know this is a lot but I really need some help

thanx
 

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when my dogbone mount snapped it made joint between turbo and manifold blow! and then month later my clutch presure plate seized up!
 

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Mokeylock
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Discussion Starter · #4 ·
It doesn't seem i have the same problem... but do you know if the flywheel can be affected by an engine mount snapping and the engine dropping a few cm ?
 

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Mokeylock
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Discussion Starter · #6 ·
yeah i was thinking of getting the EIP one at some point but i can't afford fixing the problem and upgrading the flywheel both at the moment. So if it'll mean  killing 2 birds with 1 stone by upgrading the flywheel, i'll go for it, if not i might leave it till another time.
 

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hi,

tbh. for the fly wheel to move it would take a great deal of movment and a big hammer. It may be that the balance is slightly off and the new engine mounts are exagerating the effect of this.

to set the imbalance correct i would sugest that the fly wheel is not the only thing youget checed as it is attached to the crank i would be more likely to have that looked at.

as it is a vibration i would firstly check the mounts are on propper. loosen the bolt hold the engine to the mount and run the motor. then re-tighten the bolts and see if thus helps.

good luck

dav
 

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Mokeylock
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Discussion Starter · #8 ·
thanx for that,

I've made sure the engine mounts are on ok and after getting a mechanic to check the car out it looks like it could have been the drive shaft that bent under the engine weight when it dropped... does this sound about right? i've booked the car in next week for a compleat checkup.
 

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hi,

yeah that seem more plausable than the crank.

note this would only cause the vibration during drive though.

it is quite easy to check if it is bent, just ask it if it want to go to a ghey bar :) seriously though just jack it up and run it in gear. use an axle stand if it goes it will go!!!!
 

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Mokeylock
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Discussion Starter · #10 ·
..note this would only cause the vibration during drive though...
lol I had to read that a few times to get it.

Ok about the vibration, if the problem is the drive shaft, should the vibration come on also when i let go of the gas ? at the moment it does; more noticable at certain rpms. To stop it i either step on the brake to slow the car down (and lower the rpm) or step on the gas and get the car off the rpm band that i get virbations on.
 

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Usually driveshafts show problems when under load and at certain RPM's/Speeds, kind if like an out of balance wheel.

Hard to tell without taking them off the car and inspecting if its only slightly bent.
 

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Mokeylock
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Discussion Starter · #12 ·
Ok, my best two guesses have been

1) miss alligned Fly wheel - from VW

2) Bent drive shaft - from v6 specialist/garage owner/racer/good friend

I'm taking the car in for a full diagnostic soon but what would you guys recommend i check out first? so far i think its sound like i should check the driveshaft and then the flywheel, sound about right?

p.s. what else is under the engine that might have been affected, thought if i come up with a list i can go through it and ellimenate what isn't a problem for sure.
 

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Mokeylock
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Discussion Starter · #13 ·
...to set the imbalance correct i would sugest that the fly wheel is not the only thing youget checed as it is attached to the crank i would be more likely to have that looked at....
What's the crank?

is it the prop shaft/driveshaft? the bar below ?

(ps this is off an audi A6)
 

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The crank is at the bottom of your engine. Its what the 6 (in your case) conrods attach to, which in turn attach to the pistons. So as your pistons move down the barrel, they push the conrod down, which turns your crank, which turns the flywheel, which turns the gears, which turn the driveshafts, which turn the wheels [:p]

Hope that makes sense. However it is very unlikely this is knackered. Driveshaft gets my vote
 

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Mokeylock
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Discussion Starter · #15 ·
The crank is at the bottom of your engine. Its what the 6 (in your case) conrods attach to, which in turn attach to the pistons. So as your pistons move down the barrel, they push the conrod down, which turns your crank, which turns the flywheel, which turns the gears, which turn the driveshafts, which turn the wheels [:p]

Hope that makes sense. However it is very unlikely this is knackered. Driveshaft gets my vote
so crank = camshaft?



(I get the rest, thanx [Y])
 

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Mokeylock
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Discussion Starter · #16 ·
btw, where in this process does the rear diff engage if u have 4wd? lets say if car is on snow and esp off (i.e. 4wd on all the time)
 

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Mokeylock
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Discussion Starter · #18 ·
<-- Crank?

btw, were does the propshaft connect to on the front side ? (not the haldex side... on 4wd)
 
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