Valve shim adjustment turns into desperate search

[Dragonslayer]

Out of all of the maintenance/repair/mods that I've done to my MK11 (which includes just about all of them) I've always dreaded the Valve Shim adjustment Task. And now I know for good reason. To me this maintenance task requirement is one on the biggest negatives of the Yamaha V-4 engines.

 

I've read all of the articles and manuals written about this task and had a good general understanding of the process. But, having studied up on the subject, the task really struck me as a major PITA for several reasons.

 

My first reservations were about work space access to do tedious micro measurement task in a confined area with my ageing eyesight and fat clumsy arthretic fingers. (And my seemingly constant lack of suitable and locatable lighting source issues.) Visualizing the task, I just could not imagine it being physically possible to actually do.

 

But, of course it is. In fact, as RandyR (who graciously agreed to help me) and I discovered my fears were unfounded and the factors I feared the most were actually quite easy.

 

Thats not to say that the job was without it's obstacles and did in fact turn into a major PITA, as I first suspected but, for very different and unforeseeable reasons that I never would have imagined.

 

The first problem that presented itself was a tool issue. The feeler gauges needed for the measurement of the valve/shim clearences needed to be within certain ranges for the intake and exhaust shim specs. We discovered early that the offset or bent gauges made access easier than the flat ones. Then of course the set I had on hand was not that type and had the measurement markings rubbed off...... Of Course. :doh:So we jumped on the bikes:7_6_3[1]: to ride around the corner to the nearest Advance auto parts store to remedy that situation.

 

Four Hours, fifty miles and multiple stops at every,Auto Zone, Napa, Pep Boys and Northern Handyman retail locations we could find we eventually discovered that each of them sells several different type sets but no one set contained all of the gauges we needed in the exact sizes we needed..... Of Course.:doh: We finally settled for having to buy multiple sets which we adapted to satisfy our needs. At least it was a nice day for a ride.

 

That problem solved, the next wrestling match was mental due to a counterintuative issue resulting from the tightening of the valve from wear rather than loosening (as Randy explained it to me and one might imagine). Or more specifically how that translates mathmatically (Not my long suit) for the proper replacement shim selection.

 

Being somewhat mathmatically challenged at that stage of the day, I left all the mathmatical calculations, converstions and contemplations to Randy who seemed to be good at it and really getting into it.

 

But evidently, it was a long day for both of us because after completing the clearence measurement for each valve, the out of spec shim removal and installation of the "correct" replacement shims we remeasured the valve/shim clearence on the replace shims to check our work.

 

To our dismay the "corrected" clearences were ten times more out of spec then they were before we "Fixed" them. Apparently, when doing math calculations decimal point placement is critical. Who would have thunked it? After all, who really spends a lot of time mentally dealing with decimal points and metric converstions unless your like ah counting money. :mo money:There are probably a lot of people like Randy that are good at and get into that sort of thing. I myself, am more of a generalist. I know it, I admit it.

 

Upon that realization, we decided to call it a day and regroup for the next. The next day, being armed with the mathematical truth of the error of our ways we jump into the appropiate corrective action with fresh minds and energy.

 

Note to self: When things appear to be going smoothly, it would be prudent to pay extra special focused attention and proceed with extreme caution.

 

I'm not sure if the foregoing concept is one of the reconized "Murphy's Laws" or not, but, if not it should be.

 

Half way through the secondary corrective-corrective action shim replacement, we find for no explicable reason, a stubborn valve shim that refused to be removed from it's shim bucket....Of Course.

After repeated failed attempts Randy gives up in frustration so that I get a chance take my shot at it.

 

Being the adaptive,suedo-mechanical engineering master mind that I think that I am, I immediately decide that it is another tool issue and decide to apply a jeweler's screw driver to the problem. Finding the smaller blade more accessable to take purchase on the shim it apparently lacked the tinsel strength necessary to be used as a pry bar. As I soon found out.

Suddenly there was a barely audible snap sound as I noticed the end of the screwdrive bit had broken off. But, where did it go?

 

Could it have fallen down the open spark plug hole into the cylinder directly below? If so it has proven to be unretreavable thus far using a telescopic magnet. Or could it have flipped over and fallen down the space along side of the timing chain down into the dark oiley bowels of the engine inevitably destined to be the perverbal "monkey wrench in the machinery". If I ignore it's disappearence and relocation.

 

So far it is nowhere visually or magnetically apparent within a six foot radius in all directions that I can tell.:bang head: The only recourse I can think of after days of searching is to start a disassembly process on the bike until I either find it or hear it hit the floor.

 

Any suggestions?

[Yammer Dan]

No suggestions but good luck.

[Sling]

The first thing I would do is sweep the floor. You may think it went into the engine, but sweeping around the area and picking up the junk you swept up and look through it. You might get lucky!

Just a thought:

Did you look really close to see if it was stuck in with the shim?

Sorry i have no more ideas

[painterman67]

ok I posted on the other thread there is two so Im confused

 

 

 

david

[Flyinfool]

How big of a piece are we talking about?

If it is just a tip of a jewelers screwdriver, you could do a complete engine teardown and not find a piece that tiny.

Not saying that you should not be concerned about it.

I would do a bunch more looking around the spot it broke, It might be wedged in tight enough that a magnet cant pull it out.

 

Tough decision.

 

Good luck

[dingy]

This thread may help with those pesky math calculations. It is an Excel spreadsheet to calculate required shims based on existing clearance and existing shim in motor.

 

Would work best if you had a laptop in garage while you are adjusting valves.

 

http://www.venturerider.org/forum/showthread.php?t=43410

 

Also attached is a form that can be used to record the valve clearances as you take the readings. Open the attached picture & print it out.

 

Gary

[Dragonslayer]

How big of a piece are we talking about?

If it is just a tip of a jewelers screwdriver, you could do a complete engine teardown and not find a piece that tiny.

Not saying that you should not be concerned about it.

I would do a bunch more looking around the spot it broke, It might be wedged in tight enough that a magnet cant pull it out.

 

Tough decision.

 

Good luck

The piece I'm looking for is about 1/8" in diameter about 1 1/2" long. It's not wedged in at the place I was using it I think it was more likely to flip up and land somewhere... out of sight.

[wes0778]

Think Harbor Freight has a relatively inexpensive Boroscope type tool to look in the spark plug hole...

 

Found it!!!

http://www.harborfreight.com/wireless-inspection-camera-with-24-inch-color-lcd-monitor-66550.html

Edited November 7, 2010 by wes0778
add URL

[Dragonslayer]

This thread may help with those pesky math calculations. It is an Excel spreadsheet to calculate required shims based on existing clearance and existing shim in motor.

 

Would work best if you had a laptop in garage while you are adjusting valves.

 

http://www.venturerider.org/forum/showthread.php?t=43410

 

Also attached is a form that can be used to record the valve clearances as you take the readings. Open the attached picture & print it out.

 

Gary

I had the laptop set up in the work area like you suggest and read that thread the only problem was this is a new laptop and I didn't pony up for microsoft office/excel. I use the freebe Open Office suite which is supposed to be compatable with excel but it would not open the attached file. So we did it the old fashioned way.

[Dragonslayer]

Well the search ended. Just as I thought might happen as I was disconnecting and nudging the radiator out of the way to get a good frontal view, I heard a ping and there it was on the floor. On to the next step.

[RandyR]

OK. the next problem is the stuck valve shim.

 

Its the outer intake shim on cylinder #2.

 

This shim was already replaced once with a new shim where I used the incorrect decimel point to compute the replacement shim size (along with about 10 other shims).

 

Used Dingy's churchkey custom shim remover on it, but can't seem to get a good angle with it. So was using small screwdrivers. That combination seemed to work ok the first time around.

 

Engine was spun about a dozen times with the 1st replacement shims and then we came back thru to measure the resulting clearance.

 

had correctly replaced 3 shims on cyl #1 and another on cyl #2 before we got to this one that won't budge.

 

had lightly lubed the shims with engine oil before inserting them on the buckets.

[MikesBike]

What about a shot of compressed air between the shim and bucket? Just enough to loosen the suction caused by the oil...

[dingy]

Attached is the valve shim sheet in a different format.

 

Try and see if it will open in your software.

 

I had to put it in a zip file, software on this site would not allow an upload of an XML format file.

 

Gary

[RandyR]

What about a shot of compressed air between the shim and bucket? Just enough to loosen the suction caused by the oil...

 

We can try it. I'll take my compressor when we work on the engine again. probably a couple days from now.

 

I was also thinking along the lines of some WD40 since the engine oil will be changed anyway.

 

Keep those ideas coming in....

[RandyR]

Attached is the valve shim sheet in a different format.

 

Try and see if it will open in your software.

 

I had to put it in a zip file, software on this site would not allow an upload of an XML format file.

 

Gary

 

Gary,

 

Thanks. I can't get either version running at my laptop also using Open Office. If anyone running OpenOffice can run these sheets, please let me know how?

[Grisolm1]

If I read the thread right the offending valve had the wrong shim installed. Is the new shim too thick? What is the clearance for this valve now? This might be preventing it from snapping out..... In this case loosening the cam caps may be the logical next step.

 

I did mine last year and not looking forward to doing it again for a long while. Main PITA is taking everything off so you can get to them. Once you have access, not so bad.

 

When the shims came out there was a definite SNAP to each one when they were pried out of their snug resting spot.

[Guest Swifty]

To our dismay the "corrected" clearences were ten times more out of spec then they were before we "Fixed" them. Apparently, when doing math calculations decimal point placement is critical. Who would have thunked it? After all, who really spends a lot of time mentally dealing with decimal points and metric converstions unless your like ah counting money. :mo money:There are probably a lot of people like Randy that are good at and get into that sort of thing. I myself, am more of a generalist. I know it, I admit it.

LOL...and just previous to reading this post I read one about a father labeling his son as "brainiac, not mechanically inclined"...I guess they aren't mutually exclusive after all...

Thanks for making me feel like a mechanic...mine went much smoother...for not being a brainiac that is...

[kbran]

Right click on the file and select open with and use open office calc. Both files opened with Open Office for me. The zip file had to be extracted before I could select open with.

[Snaggletooth]

Well.....I just opened both files with Open Office. Save the valve shim file form Dingys post to a file on your computer. Then go to your Open Office and select "Open" from the drop down menu and select the valve shim file from where you stored it. Should pop right open.

 

If that don't work PM me with your e-mail and I'll send you copy of the file to try that way.

 

Mike

[Dragonslayer]

We can try it. I'll take my compressor when we work on the engine again. probably a couple days from now.

 

I was also thinking along the lines of some WD40 since the engine oil will be changed anyway.

 

Keep those ideas coming in....

Randy,

 

I have a compressor we just didnt have it set up yet since our move . I'll have Clint do that this week. Read the Pm i sent you about slightly distorted shim bucket.

[RandyR]

If I read the thread right the offending valve had the wrong shim installed. Is the new shim too thick? What is the clearance for this valve now? This might be preventing it from snapping out..... In this case loosening the cam caps may be the logical next step.

 

I did mine last year and not looking forward to doing it again for a long while. Main PITA is taking everything off so you can get to them. Once you have access, not so bad.

 

When the shims came out there was a definite SNAP to each one when they were pried out of their snug resting spot.

 

Actually the incorrect shim we're trying to get out is too small, not too large. thanks for the idea though.

[Dragonslayer]

If I read the thread right the offending valve had the wrong shim installed. Is the new shim too thick? What is the clearance for this valve now? This might be preventing it from snapping out..... In this case loosening the cam caps may be the logical next step.

 

I did mine last year and not looking forward to doing it again for a long while. Main PITA is taking everything off so you can get to them. Once you have access, not so bad.

 

When the shims came out there was a definite SNAP to each one when they were pried out of their snug resting spot.

Yes you read the post correctly. However, the problem with the "too fat a shim theory" is that it went into place easily when we installed the wrong one. I'm kinda thinking a "slightly distorted shim bucket theory" due to a miss alignment of the shim tool.

[RandyR]

I was able to load and run Dingy's calc file. Thanks. yep. needed to extract it from the zip file first.

 

Thanks all

[RandyR]

Yes you read the post correctly. However, the problem with the "too fat a shim theory" is that it went into place easily when we installed the wrong one. I'm kinda thinking a "slightly distorted shim bucket theory" due to a miss alignment of the shim tool.

 

Now that you've found the screwdriver blade, we won't be afraid to turn the engine. so can remove and re-insert the shim tool.

[Dragonslayer]

What about a shot of compressed air between the shim and bucket? Just enough to loosen the suction caused by the oil...

I thought of that too.