valve stem seals and guides

The other day I had sync the carbs... when I pulled the YICS tool out there was oil on it... so I am replacing the valve stem seals and guides... when I replace the guides do I need to remove the head???

 

Yes.

But I wouldn't yank the head to replace the valve stem seals just because there was some oil in the YICS passage.

Do you have any other signs of leaking valve stem seals?

 

Before you get too far ahead of yourself ... why not CLEAN the YICS Passage and keep an eye on it for a month.

The YICS Passage is basically one straight hole from one side to the other.
Use a Dowel.
Push Carb Cleaner soaked Patches through the Passage.
Give it a good Cleaning.

Close one side.
Put your Thumb over the Open side.
Run the Bike.
Sneak a Carb Cleaner red Tube in between your thumb and the Passage.
Shoot Carb Cleaner in there while the Bike is running.

 

I have been fighting a fuel problem with it and got that fixed... which i think the fuel problem covered up the oil problem... now the spark plugs showed signs of oil... Exhaust shows blue smoke which if I am right is an oil problem...

However, I have been reusing the same spark plugs... Taking a fine grit sand paper and cleaning them off... Is it possible for spark plugs to absorb oil/fuel and when they heat up to be drawn out???

Also, I recently found out that if you pull the head there are 2 nuts that need to be replaced... I wonder if the previous owner had the head off and did not replace those... could that also be a possible oil problem...

I'm going to get new plugs and shot some carb cleaner in YICS passage...

So I know.. what are signs of bad valve stem seals???

One last thing... my friend is like MacGyver and I'm more MacGruber... But he was wondering if you could use a vacuum cleaner to sync carbs...

 

If the Bike "Smokes" for a moment; right after you start it up, then quits smoking, ... that's one sign of bad Valve Seals.

Disappearing Oil is another.

The Oil Level creeps down, ever so slowly, ... and there's no sign of a drip or leak.

 

you could pull the carbs and look in the intake with a flashlight. If there would be oil there if it was THAT guide seal. if it smokes and goes away it could be exhaust guide seal or rings. looking at the sparkplug and what you can see of the piston through the plug hole should give a better idea of whether it's rings or not.
My thinking is that there are all sorts of tests and investigation you can do for nothing more than your own time but the moment you undo those nuts on the top end you just bought yourself a new head gasket and a bunch of work. Likely for something that didn't need it.

Fitz tells a good story though about using the bucket hold down tool of never really being able to seat it right until once taking the cams away so he could SEE what's going on and then being able to easily use the tool with cams in situ from there on forever more.
I can definitely understand the perceived need to pull the top off and have a look but man would I kick myself if I did so needlessly, as in if there were any possible work around or trick of the trade to avoid doing so.

 

Have somebody follow you.
Go to where you have road going downhill for a ways.

Accelerate down the hill.
Close the Throttles and coast.

When you open the Throttles after coasting, ...
If the Engine chuffs-out a blue-colored exhaust cloud, ... your Valve Seals and Guides are leaking.