Cam chain tensioner

[puv]

Here's another one for ya. Before I start hitting that power band I feel like I need to make sure the cam chain tensioner is working properly. I just have that stupid Yamaha service manual and I can't find a way to remove it unless the motor is in over-haul state. Can you guys give me a brief walk-through on what I need to do to remove it and make sure it is working. If I'm correct when adjusting it I should hear a little clunk or noise. I hear nothing and remember this bike has "sit-itis and I'm just making sure everything is working right. The engine seams a little noisy especially when cold and at low RMP's I can hear a tick (I think I asked about this before). I seams to be comming from the cam chain area. I appreciate your guy's help. Thanks,

puv

[John]

The tensioner is located on the front of the engine, between #2 and 3 cylinders. It is the thing that is sticking out of the cylinders. It is held in by just two bolts. Very easy to remove.

[randy]

Your 'tick' could be an exhaust leak, same area. There's nothing in the tensioner that could 'tick' unless the lock bolt is loose! Yikes! I hope not.

[puv]

The lock bolt is tight. I have adjusted the tensioner a couple of times and made sure the bolts are tight. I'm not exactly sure where the tick is comming from. It seems to go away after it warms up good though or at least get quieter. I am concerned that the tensioner is not working properly. It's just a thought though. Being more of a parts changer than a trouble shooter I'm just shooting in the dark here. Is there anything special I need to do before removing the tensioner?

puv

[randy]

YES

Turn the crank to the "C" mark, and after you remove the tensioner,

DON'T TURN THE CRANK UNTIL AFTER YOU PUT IT BACK!

If you turn the crank with the tensioner removed, you can jump the chain off of the sprockets, even by a couple of teeth, upset the valve timing and risk valve-piston contact. This is valve death.

[puv]

Thank you. How about reinstalling it. Can I put it back in and then adjust it as usual? I guess I should ask also, do they get gummed up and fail on occasion? Or am I most likely shooting a dead horse here.

[randy]

Yes, just put it back in and re-adjust as usual.

Tehy don't get gummed up, but what can happen to them is the plunger gets a burr in it where the lock bolt contacts it, which can prevent the plunger from moving the way it's designed.

You can file out the burrs and re-assemble. Be careful of the spring it is under mucho tension and will launch the plunger across the room when it's released!

[TopCatGr58]

Hey PUV,

When there's not much slack to take up, when you do the adjustment process you may often NOT hear that click sound. Before taking it off...don't loosen the adjuster bolts/nuts, then when you take it off, make a little score mark across the adjuster shaft next to the adjuster housing, then loosen the lock nut and lock bolt, and see how much farther it slides out towards the engine direction. If it slides ~1/2 inch or so, then you probably haven't run out of adjustment YET! Push it back in way past the scored notch, and lock it in place. THen with a new gasket put it back on the bike. After tightening the mounting bolts, then do the adjustment...unlock ONLY, DON'T ROTATE THE ENGINE, and you will NOW hear the infamous click and the plunger springs into position, taking up all the slack it can. Lock the bolt and lock nut, and DRIVE!

Your tapping sound could also be a valve bucket/lifter tapping against the cam lobe due to slightly excessive clearance, that diminishes as the engine warms up, the parts expand and the clearance decreases!? I just measured my clearances, and 1 intake is at .08 instead of the max .06in but it doesn't bother me, a little tapping noise, was more worried about not enough clearance, more chance to burn valves that way!
T.C.

[puv]

Right on... TC I think you may be right about the valve tapping. It's not major and like I said it does seem to go away after it warms up. I'm still learning this bike and I haven't even ran it past 60mph yet. I'm testing it out this week with short little jounts to work and back increasing the distance each time. I want to get out on the highway ASAP but I have been babying (learning) it after all the crap I've gone through with it so far. I think my nerves are still frazeled having been in the trans. four times and never working on one before. That should say something about all the great advise around here. Thanks for the help guys.

puv