urgent, loose crank sprocket on my 81 rabbit

[RabbitJockey]

so i have this 1981 rabbit and today after i changed the oil i noticed it was making a weird squeaking noise especially when i revved it a little, i figured it was the alternator and took off down the road, so it sounded terrible and i pulled over to check it out, and it thought it was just the vbelt pulley so i drove home to tighten the allen bolts, i was horrified when i saw that it was the 17mm bolt in the center of the crank, so i tightened it up to i think 120 foot pounds.  and my car ran better afterwards haha.

question is, do i need to be worried about this happening again?  Is my car sesceptible to the wearing crank nose like an AAZ?  It's an 81 ls with ac, and the ac works and i do use it.  considering its an 81 it could be an 11mm motor, but i don't know if it is or not.

thanks for any help

the ***

[Luckypabst]

I can't help you but I wanted to say - that thing is pure class! I love it...

Chris

[RabbitJockey]

haha thanks!  i emphasize it too, its getting polished le castellettes and it already has a cadillac hood ornament

[Vincent Waldon]

The early engines were not particularly "susceptible" to damaged crank keyways but they do use an older, non-stretch bolt that can work loose, like any other bolt.  VW introduced a new bolt (12-point) to help address this tendency.

The really safe thing to do is to pull the sprocket and see what's going on... replenishing the sprocket and bolt.

If you can't do that, the next best thing would be to get a new bolt, torque it down to spec, and keep an eye on it until the next time you change the timing belt, at which point you pull the sprocket.

[RabbitJockey]

i'm just going to keep an eye on it until timing belt time, which shouldn't take long since i drive alot haha.  but this also solved a mystery problem i was having with smokey start ups that kept getting worse and worse, even when the engine was warm and it was hot outside it out smoke white until i drove a  little bit.  also since i tightened it the power increased a lot.  i'd compare this car to a stock td now, its so smooth and quiet also.  idles a little rough tho, but thats just how these motors are when the fuels turned up

[RabbitJockey]

[jtanguay]

did these cars come with the reuseable crank bolt? my polish mechanic friend said he re-used them all the time, and they didn't rust like the new ones did.

if they dont have a reusable bolt, you might want to either change the crank bolt, or driving style. remember its the reverse thrusting on the crank when the engine goes from 5k rpm down to idle.

[thedeezel]

Take the bolt back out and use a dab of BLUE lock-tite and retighten it, dont use th RED or you will never get it off again without heating the wee out of it.  I had the same trouble on my 80 rabbit with a 1.5na, I used the blue and kept rechecking every time I rotated the tires and never found it loose again.

[RabbitJockey]

thanks i'll do that!  haha have u ever used green loctite?

[fatmobile]

If that was the later sprocket, the bolt loosening that much would have caused the key to let loose.
 There is a key in your crank, wearing back and forth on it probably wasn't good for it.
 I'd suggest removing the sprocket and taking a look at the key,... and replace it if it got too worn.
 If it did wear and the sprocket is allowed to move back and forth, it could loosen the bolt right up.
 I think the torque on that bolt might be 148 ft lbs. ... at least it was on the JK block I just did.

[thedeezel]

I haven't used the green before, I keep the red and blue on hand.

By the way, looks awesome with the polished wheels, but whats up with the graveyard pics?  Reserving a spot for the Rabbit when it succombs to the rust demons? Which looks like it will be awhile  

[RabbitJockey]

haha i just wanted fancy stuff in the pic so i went to a church and then decided the cemetary would be cooler.  i was looking and the crank actually wobbles a small amount, less than a mm, but very noticable.  this week end i will remove the sprocket and see whats going on.  hopefully i won't need a crank other wise i guess i will need another car until i have time to fix this thang, i guess i could put a clutch in and at the same time put a crank in wiht the engine still in the car.. how ghetto, but as long as the crank i have here is in good shape, i don't see a reason not to do it this way since this engine runs extremely well.  it honestly feels as fast as my dads 85 td, i bet i could keep up with him until 50-60 mph

the green loctite is supposed to be permanent, we use at my work sometimes.. i dunno why tho haha, i broken alot of brass fittings not knowing they had green loctite on them.  but heat makes them come right out

[RabbitJockey]

the torque spec is 137 foot pounds btw

[burn_your_money]

I have a sprocket with your name on it if you need one.

[RabbitJockey]

nah i got one here on a spare short block that has been handle multiple times haha