valves too tight?

[doubleextramayo]

So I have a 1979 xs400 sohc that needs some valves adjusted. Trouble is, I can't seem to jam a single feeler gauge in there at any point of the sequence, and most definitely not at TDC. Am I just worrying too much and my valves are just that far out of spec, or could it be something else?

 

[arfstrom]

some people will use a pencil, others will use large plastic tie. Of coarse you can see the lines for LT (left Top Dead Center) or RT Right cylinder TDC. The manual has a special line, that I can not remember about the valve open/close, and something or other.

Its my way of saying check the manual. Always double check the manual.

 

[doubleextramayo]

OK after a bit of reading other peoples threads with similar issues, I believe I've done the left side correctly. Now my issue lies with the right cylinder. I only have one mark that I can see. There's a LT and an LF for the left that I can see but I only have one R_. There's a lot of scuff marks and I can't make out if its a T or an F. It feels as though when I get this mystery mark on the indicator, the cylinder is done the cycle and not at TDC but at RF instead. Could I just assume that my TDC mark for my right cylinder looks the same as my left cylinder marks, but obviously just for the right cylinder?

 

[xschris]

RT is after the RF marks. Just make sure you don't move the flywheel back at all to catch it or it will put slack in the cam chain throwing the adjustment off. I think it is two revolutions of the motor at TDC left to get TDC right.

 

[doubleextramayo]

Would I be able to assume that its EXACTLY two revolutions past TDC left?

 

[xschris]

I have not done it in a while, but I think it's two revolutions. Shine a light down the plug hole or use a wooden dowel to make sure the piston is at the top.

 

[doubleextramayo]

NEW PROBLEM! the bolt used to crank the engine started backing out... What did I mess up and how do I reverse it!?

 

[xschris]

You will need to re-torque it into place. Make sure the bike is out of gear and the spark plug are out of the motor when you set the valves next time. This will give little resistance on that bolt.

 

[doubleextramayo]

I didn't completely KO anything though, right? Would you know the torque spec on that bolt of the top of your head?

 

[doubleextramayo]

When I try and turn it back to re-tighten the bolt it seems like the motor just wants to spin backwards, and I read somewhere that that's not a good idea to do. How do I keep it from rotating so I can tighten this SOB back on?

 

[xschris]

22-25lbs. As long as the wheel stayed on and key for it didn't move.

 

[xschris]

When I try and turn it back to re-tighten the bolt it seems like the motor just wants to spin backwards, and I read somewhere that that's not a good idea to do. How do I keep it from rotating so I can tighten this SOB back on?

Put it in gear and set the rear wheel on the ground.

 

[doubleextramayo]

OK. Drop the valves entirely. Maybe even shut this thread down. I broke one of my screwdrivers off inside the valve trying to feel around for TDC. Valves just got put on the back burner for a while... Xschris, you seem to have taken pity on me. What's my next step for extracting the screwdriver tip? The screwdriver was in the spark plug hole.

 

[xschris]

I have not done it in a while, but I think it's two revolutions. Shine a light down the plug hole or use a wooden dowel to make sure the piston is at the top.

Never use metal Don't turn the motor over!!! Use a magnetic wand to try and fish it out. If you can't get it the head will need to come off.

 

[arfstrom]

some people will use a pencil, others will use large plastic tie. Of coarse you can see the lines for LT (left Top Dead Center) or RT Right cylinder TDC. The manual has a special line, that I can not remember about the valve open/close, and something or other.

Its my way of saying check the manual. Always double check the manual.

Those plastic zip ties are alot better, and dont fall apart. Now, you going to try a magnet. Magnatize a screwdriver, or see if you get a very narrow circumference magnet wand. My IKEA kitchen knife holder is made up of 10 to 16 long thin strong magnets that would be awesome for what you need to to.

I suppose a vacuum might be easy to do as well. get a shop vac, and reduce down to the size od = smaller than the sparkplug hole, (not sealed)

My assumptions are that the screwdriver tip is of iron ore, and you didn't inadvertently punctured your piston.

 

[doubleextramayo]

There's a good chance it's sitting on top of the cylinder right? I haven't touched the engine at all since then.

 

[xschris]

It should be. How did it break off? Was it pinched by a valve of smacked by a piston?

 

[doubleextramayo]

Smacked by a piston. PSA: Don't buy fuller screwdrivers!

 

[doubleextramayo]

Haha! I got it out!

 

[xschris]

Awesome