Did valve clearances, new noise. Normal, not normal?

[photojournalyst]

Valve clearances on a 52k '96 R1100R. About 6k from the last valve job. Did that, turned the bike over since it's in storage and a little running is not a bad thing, and now I get a sound like an air compressor from the right hand jug.

 

Valves done poorly (first for me, but it happens) or something new?

 

Any thoughts?

[redryder]

Is the spark plug in? And have you inspected it to make sure the porcelain center isn't leaking? Only time I ever heard an engine make an air compressor sound was one time when a spark plug broke in my dad's pickup. Could be something else, but that's just my input.

[RightSpin]

If your intake valves are set too tight, I would imagine they would make a similar sound. It would be worth having another look (preferably with someone who has done valves before) to make sure. Tight valves will overheat during the normal operation of the motor.

[Stan Walker]

I hate to even ask this......but.......

 

You didn't adjust both sides of the engine at the same TDC......

 

Another stupid question. The sight glass (for oil checking) is still there? Sometimes they blow out and make a funny sound like you describe. Of course they also make a big mess. About the same noise if you forget to install the oil fill plug.......

 

I'll crawl back into my hole now......

 

Stan

[Jim Moore]

Make sure your rubber donut is seated correctly in the spark plug hole. You can check it by pulling the plug wire and looking in the hole. It will be obvious if it is lopsided.

[Joe Frickin' Friday]

I hate to even ask this......but.......

 

You didn't adjust both sides of the engine at the same TDC......

 

I would not expect this to sound like an air compressor. Instead of sub-millimeter valve lash, you'd have clearances on the order of 8 or 9 mm on the side that was adjusted at TDC-ignition; the valves on that side of the engine simply wouldn't open at all.

[Stan Walker]

I would not expect this to sound like an air compressor.

 

I suspect you may be right. But I've never done it to find out and it is the last area the original poster worked on.

 

Stan

[Wooster]

I would not expect this to sound like an air compressor. Instead of sub-millimeter valve lash, you'd have clearances on the order of 8 or 9 mm on the side that was adjusted at TDC-ignition; the valves on that side of the engine simply wouldn't open at all.

 

Gee Mitch,

Now I'm confused. Top Dead Center happens twice, at compression (which might also be called ignition) and exhaust. Valve clearance adjusted when cylinder's at TDC compression should be fine; after all, that's SOP. Valve clearance adjusted when cylinder's at TDC exhaust should produce excessive clearance yet not at the 8 mm level you suggest. Lastly, I made this mistake, i.e., adjusted both cylinders' valve clearance when one was @ TDC compression (fine) yet other was at TDC exhaust (not so fine). I ended up with a loud, clattering airhead (R75/5) which took me a hundred miles to the dealer w/o any power loss.

I may be missing something here; if so, what's up ?

Wooster

[Joe Frickin' Friday]

Now I'm confused. Top Dead Center happens twice, at compression (which might also be called ignition) and exhaust. Valve clearance adjusted when cylinder's at TDC compression should be fine; after all, that's SOP. Valve clearance adjusted when cylinder's at TDC exhaust should produce excessive clearance yet not at the 8 mm level you suggest. Lastly, I made this mistake, i.e., adjusted both cylinders' valve clearance when one was @ TDC compression (fine) yet other was at TDC exhaust (not so fine). I ended up with a loud, clattering airhead (R75/5) which took me a hundred miles to the dealer w/o any power loss.

I may be missing something here; if so, what's up ?

Wooster

 

You're right; my brain's going soft. Valves are indeed supposed to be adjusted at TDC-ignition. Attempting to adjust them at TDC-intake (when they are all partially open, rather than fully-closed) will result in significantly larger-than-normal valve clearances. Valves will open late and close early, and I suppose this could affect the breathing sounds. Seems to me you'd expect a lot of clatter from that side of the engine though.

[strat]

so what is the normal way to designate compression TDC. On my Harley I just looked for the intake lifters to close then I knew I was on the compression stroke. I'll be doing all this service stuff soon as the riding season nears and I really don't want to blow it.

 

Thanks

strat

[photojournalyst]

It was the rubber seal in the sparkplug hole. Not only was crank compression getting out, but oil was everywhere too.

 

I cleaned all the oil off of all mating surfaces carefully, and re-applied to cover.

 

Happy tapping sounds all around.

 

Once again, the board rules!

[Wooster]

strat,

 

That's it; simply look for intake valve to close then you know next TDC mark will have that cylinder on TDC compression (where you need to be to correctly set valve clearance). Given the 180 degreeness of our boxers, we can then assume the opposite cylinder is at TDC exhaust: this last fact is useful only if you're using the little opening (covered by that pesky rubber plug) to ID TDC. If so, you're stuck on the right side of bike looking in that opening for marks on the flywheel and knowing that right cylinder's exhaust valve closes then you see TDC mark, you've got left cylinder at TDC compression.

I suppose Mitch's term (TDC ignition) is as appropriate as TDC compression (means same thing) though I'm more familiar with the latter.

Two additional valve adjust points, namely, you don't need to mess with pesky rubber plug (pia to re-insert); you can look for small arrow on cam chain gear; when arrow is parallel to ground and pointing out, you've got TDC; then by using your sound method (looking for intake valve closing prior to arrow rotating to parallel, pointing out) to ID TDC compression. Second point is that R1100 motors have a small brass colored thimble/cap between rocker arm and valve stem's end; this cap needs to be wiggled (by you) prior to inserting feeler gauge. Sometimes this cap is stuck (needs wiggling) which impedes accurate clearance measurement. Oh yah, a third point is that you needn't go thru hassle of removing alternator cover to rotate crankshaft; getting bike in top gear, you can rotate shaft by turning rear wheel (with spark plugs out). This last "dance" is contorsionistic, i.e., lying on ground using foot to turn rear wheel while eyeballing valve gear and that small cam gear's arrow.

 

And congratulation to Quelich for solving the problem. I used to wish for a life free from problems then wised up to the fact that problems are always with us. Now I wish for competence in responding to ever present problems.

 

Philisophical Wooster