Valve Shim replacement - XJ900

I wanted to share this info about valve shim replacement.

After looking at the service manual, I saw that the XJ900, and probably other XJ's, use the valve buckets with the replaceable shims of varying thickness. This is exactly the same setup on the '87 Toyota Supra Turbo motor I rebuilt for my step-son's car. I own the Supra valve shim replacement tool which is simply a hand-tool that compresses the valve shim and bucket down, and a tool that you insert between the outer edge of the bucket and the camshaft to "wedge" the valve open so you can pry up the shim. Simple process actually.

So I pulled off the valve cover the other day and did a valve clearance check on my XJ900. Sure enough, Intake #1 was way tight. So I knew I had to replace that shim.

I pulled the Supra's tool out of my box and gave it a try. It works better than on the friggin' supra! I compressed the valve, wedged the bucket and popped up the shim out. Noted it was a 285. The service manual chart cross-reference guide based upon the current clearance cited I needed a 280 to correct the issue.

I have two other motors so after checking motor #1, I had all 280's and one 275. But the second motor had a 280. Sweet.

Again using the Supra's valve tool I inserted the appropriate shim and now it's done.

Pics included. So, if you're short a tool, and I don't know how expensive the actual Yamaha valve tool is, get yourself a 1987 Toyota Supra valve adjustment kit for around $30. It works perfectly.

 

Well halaluya!! Now we have another option. $30 is not bad either. Where'd ya get it? I assume Toyota sells them, but could probably get it for less at an auto parts store maybe?

 

No way at the parts store. I looked into my paypal account history and I got it from ZDMAK tools. Actually, for use on the bike it'd be only around $17 bucks plus shipping. I ordered this one (below) because I wanted the Toyota OE head bolt socket which is a special Allen head:

http://zdmak.com/wbstore/main.asp?actio ... =1&LowCt=0

But all you'd really need is this one:

http://zdmak.com/wbstore/main.asp?actio ... =1&LowCt=0

So my mistake on the price. I forgot about the special Supra head bolt socket. I didn't even need it because this Supra motor already had the ARP style head-stud upgrade which, of course, I replaced with new ARP hardware but wanted the socket just in case another one came across my path.

 

Let me clarify this proceudre after receiving an email question from Chacal:

What this tool compresses against is the camshaft AND the valve shim/bucket itself. It pushes the whole lot down. Then the small dog-legged looking part wedges between the camshaft and the EDGE of the shim bucket. You kinda have to feel that out and try it a couple times to get the feel. I did 24 valves on a Supra motor numerous times so I hit the mark on this bike first try on that. But what you have to do first is have one of those telescopic magnet gizmo's at the ready too, a small flat-bladed screwdriver AND, you have to rotate the shim bucket so the pry slot is visible. But when you insert this tool to compress the valve, it will tend to rotate the valve shim bucket in the direction in which the tool is contacting it. For example, if you crank down on the bucket at the 2 or 3 o'clock position, it'll rotate clockwise. On the 8 to 10 o'clock position, counter-clockwise. So you have to set up the shim pry slot about 30 degrees opposite the anticipated turn direction so after you crank down, the shim slot will be right where you want it.

Yes, you can possibly turn the shim slot after wedging the tool but not always. See, the wedge tool tends to put some pressure on the lateral part of the shim where it sits in the bucket. No so much where it'll dislodge when you pop the shim, but it's usually enough to bind the shim where it won't turn freely at that point. So setting up the angle ahead of time is a wise thing to do.

Like I said, I did a 24-valve motor multiple times while on the engine stand so I have really good muscle memory where this is concerned and it was easy on the Yamaha. For those nay-sayers regarding the in-board valves, I checked the clearances between the #2 and #3 valves and it seems the tool WILL clear the frame tubes so it can be used on the center valves. I didn't try it physically, but based upon my experience with the tool, it'll work, trust me.

Hope this helps explain it.

Tom

 

The Motion Pro Yamaha tool is widely available for cheap and is a proven method, as is the $0 "zip tie" method (not recommended by yours truly.)

Good suggestion, but I suspect an elegant solution to a less than elegant non-issue.

 

You don't need a YICS Tool.
Just a pair of scissors and an old Tee-Shirt.

You don't need an expensive set of 4-Tube Mercury Sticks
You don't need Bottles, tubing and a Certificate in Plumbing.
Just a Vacuum Gauge and a Restricting Union.

Now, another method for servicing out Bikes has been discovered.
As time goes on, ... "The Supra Solution" may get added to the list of every innovation we have discovered for making life easier as an XJ Bike Owner.

If that Tool works on the XJ-750; I'll be getting one soon.

 

Won't a vacuum gauge bounce all over the place because of the pulsing of the vacuum? And what do you mean by a restricting union?

What do you do, shove the tee-shirt into the ports to block each one off? I'm just curious; I already have the tool. If I used a tee-shirt with a picture of my ex-wife on it, will the bike go Demonic on me?

Thanks for the feedback all.

Tom

 

It should, same block.

 

I have a junk motor out back still in a frame. If I get some time today, I'll make a quick video of exactly how this works and post a link for y'all. Gotta put back a camshaft and at least one valve bucket and I'll show ya.

 

I use the zip tie method myself - no trouble finding that tool in my garage :lol:

 

How's that method work to change out valve shims?

 

I posted a short video on YouTube to better explain this if you're interested.

Hey, I'm just trying to help here. If you don't like the technique or if you have a better one, please show us YOUR video.

Thanks for the opportunity to share my findings.

Tom

Youtube Vid - Toyota Supra Valve tool

 

Ziptie method is pretty basic, you let the camshaft open the valve you want the shim out of, then stick a folded over ziptie into the spark plug hole, and turn it so it'sin the way of the vale closing. Then rotate the engine so the cam lobe is off the shim. The ziptie will keep the valve open so you can pull the shim.

Then pick out the shim and record number/replace.

The ziptie should look like a J, bended so it'll reach beside the spark plug hole when inserted.

 

That is clever, I'll admit. However, I'd be worried that this technique would bend a valve. Valves are designed to have linear, not lateral strength. What you're saying is that part of the valve closes on the wire tie, holding it open. Well, if it works, then great. I think for $17 bucks plus shipping this Supra tool is safer and faster and no fishing! lol

But again, very clever. Thanks for the info.

 

One thing Breaker19,
You mention on your video to use a magnetic tooltoremove the shim once you have the bucket down? No, I've read here numerous times NOT to use anything magnetic on the shims, as it could magnitze the bucket and collect metal particles, etc. Just thought I'd throw that in there for ya.

 

A piece of 12/2 wire bent at a 70* (more open than a 90) is more foolproof than zip-tie. The valve stem will be under a sideways load of a fraction of the preload- - maybe 100 pounds?? the metal can take that without bending. That does seem like a cool tool to use Breaker19

 

The YAMAHA Factory Manual actually says:

"Remove the Shim from the Lifter. There is a small slot in the Lifter.
Use a small screwdriver or other blade and tweezers or a Magnetic Rod to remove the pad."

---- Genuine Yamaha Service Manual -- LIT-1116-03-46
---- Sect. 2 Pg.5 Item 5

Restrictor Union:
.........................
A Plastic Connection that joins Vacuum Lines.
Modified.
A Carb Cleaner "Red Tube" is placed through the Union.
The Union is filled with Epoxy.
After the Exoxy cures ... the Red Tube ends are cut flush.
The UNIONS Inside Diameter is REDUCED to the Inside Diameter of the Red Tube.

This Restrictor prevents the Vacuum Gauge from fluctuating wildly while taking Vacuum readings,

 

So your saying magnets won't hurt anything? OK then. I used a fine needlenosed pliers for mine anyways.

 

Let's look at some cool magnetic effects.
Drop a couple magnets in your filter on your next oil change.
Even barely magnetized shims could pose a problem.

http://www.youtube.com/watch?v=ALL1SruAH4Q

http://www.youtube.com/watch?v=me5Zzm2TXh4

 

I saw that too, in the "base 650" book, but one of the OTHER Genuine Yamaha service manuals I have cautions against using a magnet.

 

No.
I'M not saying a Magnet won't hurt anything.
I'm just quoting the Bible.

I've never seen a Caution in a WorkShop Manual that said:
Warning: Do Not Use A Magnet To remove the Shim from the Bucket.

I called YAMAHA ...
"To Magnet. Or, ... Not to Magnet?" This was my question.

OFFICIALLY
After discussion with the Tech.

"Our Service Manuals say to use a Magnet. I'm telling you, Yamaha recommends using a magnet."

 

No way. Impossible. You cannot make a magnet out of a piece of steel by contacting it for a few seconds with another magnet. I'm sorry, no offense, but that's just crazy.

 

Yeah - I agree.

If you leave the magnet in your tool box with your spare shims, however......

 

Oh, I get it... you're creating somewhat of a capillary tube. That is quite clever! I will definitely try that!

Tom

 

Re: magnetic valve shims

OK, this idea of magnetizing the valve shims from a mere few seconds contact with the telescopic magnet had me intrigued. So I decided to do my own unscientific tests.

Taking two valve shims, I cleaned them both with 70% isopropyl alcohol and a paper towel. I took some steel metal shavings from my tool bench. Fresh shavings may have some inherent magnetism from the friction of the tooling making them, so I figured old shavings were better.

Placed all on a piece of cardboard and marked each side. Test done with 10 seconds on the magnet for one shim and no magnet for the other. However, both shims were wiped down with a dry paper towel before and after each test... to get any shavings residue off.

I "dipped" each shim in the shavings each 3 times to make sure I had coverage on each edge.

Here's the pics. Scroll down for the conclusion:


Test setup, ferrous shavings on both sides. Non-magnetic to the left, magnetic to the right.


Magnet to the shim for 10 seconds, which would be way more than you'd have using it to simply pluck a loose shim from atop the bucket.


Magnetic shim, zero minutes. It does pick up some shavings.


Non-Magnetic zero minutes. As you can see, it TOO pics up some shavings.


Magnetic, 15 minutes. Still some shavings but less.


Non-Magnetic at 15 minutes. Likewise, still some shavings but less than the magnetic side.


Magnetic shim, 30 minutes. Yes, still some shavings but again, less.


Non-magnetic shim, 30 minutes. Still see some shavings.

Conclusion:

As you all are probably aware, all metal has magnetic tendencies and the ability to hold a magnetic charge. Just the mere act of rubbing a piece of metal with a towel can "charge" metal in a manner that it will act, at least somewhat, like a magnet. However, in this test, they may actually be some validity in recognizing that 10 seconds on the telescoping magnet did seem to increase the potential of the magnetic shim to pick up stuff. However, it is likewise clear that over time, that amount diminishes. The fact that after rubbing the non-magnetic shim with a paper towel apparently charged it with enough energy to pick up at least some fine metal shavings, shows this magnetic potential under certain circumstances.

I think it's not anything to worry about. Even if the shim is slightly magnetize, once it is put in place against a much larger mass of steel (the bucket itself) AND with an oil bath which will dissipate a static charge, I don't see any particles of any significance sticking to the valve shims for very long, at least.

Interesting stuff!

Tom

 

Which tool? Thanks for your input.

 

Your "Supra" tool sounds cool- - mine's just a scrap of wire.
Somebody's going to use a cheap Chinese zip-tie that will snap off in the intake runner (someday).

Your experiment seems to lack a "control" and can easily be made "scientific", or close enough. . .

If the iron filings were heated to a certain temp, they would be demagnetized and de-greased at the same time.
Or you could just cut up fine steel wool with scissors.

You should have tested the shim before magnetizing it.
But why are both shims magnetized??
I can honestly say this puts a new wrinkle on the theory.

 

I think we should magnetize the oil filter ends. Problem solved and the filter becomes more efficient!

LOL

 

You know, Breaker19 and I live too close to the Bermuda Triangle to do any REAL magnetic experiments. . . :lol: :roll:

 

That's true.. lol...

 

Yea, I was thinking about a control. The steel wool is a GREAT idea!

And what I did forget to include was, I took a third shim without doing anything but cleaning it with alcohol and it didn't pick up any appreciable filings -- except those from simply pressing against the shim. They didn't look to be attracted by magnetism.

As for why would the non-magnetized shim do that? My theory was, and is, static electricity. I rubbed the shim with a dry paper towel before and after each test, plus the initial cleaning and drying. Friction can certainly cause metal to have magnetic tendencies. But that's just my theory.

I ought to try it again with steel wool, if I have two "virgin" shims left.. lol

Thanks.

 

There we have the final answer to our conundrum: do as you please, warm the machine up and ride! The filings will do their bad deed elsewhere! :lol: