Valve Adjustment Pictorial

[BA80]

Interesting......I would like to know what the difference is.

[crazy steve]

Interesting......I would like to know what the difference is.

Greg, these things look to be sand-cast, and all I can figure is their quality control on the molds isn't too good...

[Titans]

Quick questiong guys if I may

I still cant figure out why, as the engine wears, the valve clearance decreases?

[tcoop]

As you run the engine the valve slams against the seat, each time it wears on the seat going in a little more each time. In turn it raises the bucket a little more which closes the gap between the lobe and the shim.

[andylawcc]

i have a question about measuring the gap.

In the beginning, I measured the gap whenever the pointy part of the lobe isn't touching the shim. So, for some valves, the pointy part is facing exactly opposite away from the valve (so, 180 degrees), while some are just facing "90 degrees away." Then I did my calculation and replaced with new shims. Now, after the replacement, i re-measured and found out quite a few valves didn't come out as expected / within spec, i double checked the math and it still didn't make sense.

So, after fiddling a while, I find out the lobe has tighter clearance when it is just pass touching the valve shim, and the clearance/gap increases as i turn the crankcraft and the pointy part is "180 degree away." The gap then reduces as it is pass the 180 degree spot, and getting closer back to touching the valve shim.

So I suppose the fatter side of the lobe is not a perfect circle then?

and I should use the LARGEST clearance number as base right?

[DGXSER]

Correct, the cam lobe is not circular until it gets elongated. And yes, you want to measure the clearance when the gap is the largest, or with the lobe at 180 deg from the valve. You do not need to be overly fussy about being EXACTLY 180. But you do want it to be close.

[andylawcc]

thanks again DGXSER...

[Petersg_99]

If I get a new valve cover gasket, can you remove and reinstall the valve cover multiple times, or is the valve cover gasket only good for 1 or 2 times?

What about the camshaft plugs? Do they need to be replaced when you pull the valve cover?

[natemoen]

Could use rtv and not waste time with the gasket. Cam plugs can just stay there. Don't remove them, if you do put a good layer of rtv on them before reinstal.

[bikerphil]

If you spray the new gasket with Pam cooking spray, you can remove it and use it over again. The cam plugs can be re-used, just put a bead of RTV around all edges when installing. I myself just use RTV and no gasket.

[GLoweVA]

If I get a new valve cover gasket, can you remove and reinstall the valve cover multiple times, or is the valve cover gasket only good for 1 or 2 times?

What about the camshaft plugs? Do they need to be replaced when you pull the valve cover?

The camshaft plugs should be good for years. (as long as they don't get damaged/nicked, etc.)
Some/most don't use a valve cover gasket, they use yamabond or some other RTV that they like.
I've reused my gasket quite a few times, but the hard spot with that is the gasket gets brittle and may break, thus creating a leak at that location.

[mack]

Pam

Pam's the way to go if your not using RTV. You'll probaly never have to buy another gasket as long as your careful about hooking them on something while removing them.

[bikerphil]

Pam's the way to go if your not using RTV

Yep, and the engine smells like a pizza parlor for a few hundred miles, lol.

[LoHo]

Are the little tabs on the sprocket bolt holes mentioned in Clymer's? I noticed them, but didn't know their importance...now I have to go check, dammit!

[old_chopper]

Since we've officially hijacked the thread...I use a doubled over zip tie to slightly hold the valve open then pull the shim. I feed the zip tie thru the spark plug hole between the open valve and seat and rotate the engine to close the valve. Costs about 25 cents and is super easy. I've used this method on Suzuki GS (8 valve) and my XS.