Never seen this happen before

[renagade281]

So I had to adjust the timing on a 50cc Schwinn valo scooter the other day and when I went to put the rocker arm assembly back on, u know the 4 nuts that go on the studs, well as I was tightening one of the nuts, instead of tightening it started pulling the stud out of the motor. It never tightened all the way. I thought the nut was stripped at first because it just kept turning but then I noticed that all the other studs were only sticking about 1/8 past the nut but this one was about half an inch. It has pulled it out so far that the valve cover won't even go on because the stud is too far out. What is the solution to this

[acvw74]

Seen this happen on the AirCooled VW engines....an overtight head bolt will pull the stud out of the case after the engine gets warm and the "jugs" grow from the heat...pulls the stud right out.  Use to have something called "case savers" - essentially a "helicoil" but it let you use a larger stud.

You might be able to use a "Helicoil"...but to use the same size stud you will need to drill out the old an put in the proper size coil.

[renagade281]

Sounds like more work than I feel like doing

[Deleted]

You might check to see if it's actually pulling the stud out of the case, or whether you're twisting and stretching the stud itself, that's exactly what happened with my 50cc GY6, only ultimately I didn't notice and it snapped, luckily it snapped outside the case so all I had to do was unscrew the stub and screw the new stud back in.

[renagade281]

Aug 14, 2016 21:14:16 GMT -5 peascreek said:

You might check to see if it's actually pulling the stud out of the case, or whether you're twisting and stretching the stud itself, that's exactly what happened with my 50cc GY6, only ultimately I didn't notice and it snapped, luckily it snapped outside the case so all I had to do was unscrew the stub and screw the new stud back in.

Yeah I'm gonna pull it all off today and see what's going on. That would be a good thing if that's all it did

[humanshield]

Or maybe when you unbolted it it unscrewed to the last thread or two.

Try screwing it back in. Maybe you'll get lucky.

[renagade281]

Off topic but is top dead center when the piston is at its farthest point away from the back of the motor? Like pushed all the way towards the front

[90GTVert]

Yes. Top dead center is the closest the piston gets to the cylinder head or top of cylinder. Bottom dead center is the opposite, when it's as close to the crank/case as it can be.

[renagade281]

OK I put the piston at top dead center and then put the cam back on with the holes lined up like they should but the compression is still way off. I'm gonna have to pull everything back off tomorrow and check again. I think it has something to do with that stuff not going back in right

[Deleted]

[acvw74]

Aug 15, 2016 16:26:02 GMT -5 peascreek said:

That sucks

[Deleted]

$1.19 part, lesson learned, lady luck was on my side.