Valve adjustment, tappet missing!

[singletrack]

So I mustered up the courage, materials and the tools to try my own valve adjustment on my new-to-me 750T. I get the valve cover off and to my horror one of the tappet adjustment screws is missing! I looked around the cam and found the locknut sitting on the bottom of the chamber, but the screw is no where to be found. I have a call into the local dealer to try to get a new one, but I'm wondering what I should do to try to find the old one? Would it just fall down to the oil pan? The lock nut has a couple of little dings where the cam whacked it, but is mostly in good shape.

It was an exhaust valve on the 4th cylinder. Does it basically mean I was running one cylinder shy? I'm not sure when this might have happened, it has been running about the same since I got it ~1200 miles ago.

The clearances seem to be in range, .004 for the most part. Spec is .004-.005, should I loosen them to .005 or is it OK to leave at .004?



Thanks!

 

[singletrack]

missing tappet

missing tappet

here's a picture

 

[Nessism]

You got lucky. There is another recent thread here where one of those adjusters came loose and got caught in the cam chain causing a lot of damage inside the engine.

I'd drop the sump cover off and look for the adjuster. Tighten all the lock nuts good and tight to make sure none of the others come loose.

Lastly, wasn't the engine making a ton of noise? And why did you ride the bike 4000 miles without checking the valves?

 

[Steve]

You weren't quite "one cylinder shy", but that cylinder was only breathing through one exhaust valve, so its contribution to overall power was diminished a bit.

It is possible that the screw went all the way down to the pan. I would suggest that you drop the oil pan to verify. If it didn't drop all the way down, there is no telling just where it is, possibly ready to drop down into something and cause a bit of damage.

My philosophy on adjusting clearances with threaded adjusters is this: if it's within the range, LEAVE IT ALONE.
I don't have 'the touch' that it takes to do it quickly, and I am more likely to mess up the adjustment even more.

.

 

[singletrack]

Thanks guys

@ nessism: the engine wasn't really making a ton of noise, at least any more than usual. I'm new to motorcycles so I don't have an ear for the subtleties, but there was nothing that sounded obviously off. The bike is new to me and I wasn't sure when the valves were last checked, plus it runs poorly until it warms up, valve adjustment was suggested here. I've only put about 1200 miles on it.

 

[Nessism]

Thanks guys

@ nessism: the engine wasn't really making a ton of noise, at least any more than usual. I'm new to motorcycles so I don't have an ear for the subtleties, but there was nothing that sounded obviously off. The bike is new to me and I wasn't sure when the valves were last checked, plus it runs poorly until it warms up, valve adjustment was suggested here. I've only put about 1200 miles on it.

My bad, not sure where I came up with 4000 miles.

Every new GS bike I get goes straight into the garage for a carb rebuild with new O-rings and a valve adjustment. Trying to avoid situations like yours by doing the work first thing and not leaving things to chance.

 

[Guest]

Drain the oil and it may come out there.
Drop the oil pan and see if it's there.
If not it probably is in the cam chain galley waiting for a rainy day to show its ugly head.

 

[mperryz24]

Lost Valve adjuster

Lost Valve adjuster

You might try going to an auto parts store and getting a small retractable magnetic tool/nut/bolt retreiver and send it down the oil drain holes since the head is aluminum and it won't stick to it!

 

[singletrack]

If not it probably is in the cam chain galley waiting for a rainy day to show its ugly head.

EEK! that is what scares me. I checked around the rest of the cams and couldn't spot it.

I'll drain the oil too. @mperryz2, that's a great idea. I have a magnet from an old hard drive around here someplace, was thinking of running that across the bottom of the pan, but your idea is better.

Thanks again for the ideas and advice.