Crankshaft nut

[staggerwing]

Hey guys, Dan is having a problem with his crankshaft nut working loose. Tightened it up to spec (35-39 lbs) goes for a ride and when he gets back it's loose again. What's the secret? He removed the pulley using two screw drivers as a puller and he thinks the slot in the pullley might be slightly larger than it should be? Gosh, the thing only has about 300 miles on it.

[Jack Duncan]

Removing a pulley with screwdrivers is a big NO NO. It will distort the pulley and cause a sloppy key slot, which in turn allows the pulley to shift under acceleration. That could cause the bolt to loose it's torque. It doesn't take much. This sounds like a good time to go to a serpentine system. (MST) The original pulley is made of mild steel and it's pretty soft. MST serpentine pulley is T6 aluminum and it's tough stuff. If it has to be the original type, then I definitely recommend a gear puller or a crankshaft pulley puller. (Buggy Warehouse sells them)
This is my opinion and it's free.

[staggerwing]

Update -
It already has the serpentine belt system. He said the pulley came off "really" easy, like he pretty much pulled it off without having to use the screwdrivers. Going by there tonight to take a look at it. There's a photo of the back of the car under "General Discussion" - "New Member".

[KIM-P]

Loc-tite. Red is stronger than blue but blue is more rebuild friendly and only use it on the threads if you put it on the shaft it will be more difficult to remove the pulley later in life.

[CoryN]

It's probably bottoming out. I had the same problem. I had to put a washer under the nut. That solved the problem.

[staggerwing]

I need to post a photo. The pulley can be pushed on and taken off without tools, but is a snug fit. The key fits the crank snug and does a pretty good job fitting the pulley as well. There is a large "void" under the "whimpy" washer where the head of the bolt pushes against. Tightening the bolt "concaves" the washer considerably. The bolt threads "slopily" into the crank with considerable ease and can be wobbled if you thread just the bolt by itself into the crank. With the pulley in place and the bolt and washer hand-tightened, about 1/2" of the end of the bolt threads in to the crank, seems like it should be more than that?. It just seems like there should be a spacer under that washer to support the bolt when it's tightened to spec. I wonder if just Locktite itself is enough to do the job. Do these serpentine systems have a shim or collar that sits under the bolt to fill that void? Thanks for the help guys.

[Jack Duncan]

My serpentine system is an MST. The bolt came with the setup and has a shoulder made onto the head and looks like a spacer, but is all in one. I think the bolt is too long on Dan's, as Cory suggested. It could also be the wrong bolt, or the wrong diameter. It shouldn't be a loose fit, I don't think. MST could probably supply the correct one, or at least the one they sell with their kit.

[Vee Dub Nut]

Use one of the big stock wavy washers and blue locktite.

My 2276 kept shucking the pulley bolt until I did the above.

[staggerwing]

Well, he didn't use a "stock wavy washer" but he did get a big fat washer from the local hardware store and threw some bluse Locktite on the bolt threads - so far so good. Ya'll be sure and compliment him on that washer next time you see him. I gave him a hard time about it cause it ain't chrome (like I have any room to talk).