XJ 400 - How to replace and adjust command chain?

BigFitz is fine and happy to help. Luckily we also have Markie, who is more familiar with the later XJ600/Seca II/Diversion and is able to help as well.

And it's not a case of "utter ignorance" or you wouldn't have gotten this far; you're simply "out of your element." Luckily, you fell into our sandbox. You're doing fine, and I'm already a bit bonkers so it's no issue.

 

I still do not have the "special tool" but could not hold the anxiety any longer, so I improvised (see picture). Obviously, I could only access the extremes (valves 1 and 4 exhaust and valves 1 and 4 admission, and that with extreme patience and the help of my wife turning the engine - CCW!.
What I got is this:

front of bike
[0.15 - 270] 0.15 0.15 [0.15 - 270](right side of bike)

[0.12 see note] 0.10 0.05 [0.05 - 270]

Note for admission shim #1 (left side of bike): I suspect foul play here. It has no number, and the whole perimeter of the bottom side of shim shows signs of having been filed out, creating a slight bevel (there are scratches in the middle too). Could it be the "poor man's shim pool", israeli style? Funny is, this is the only valve that comes close to the recommended gap. Did the guy get tired, assembled the rest "as is" and came out with the lousy excuse that "the cylinder must be cracked"?
Please tell me what can be inferred from this information.
Aharon

 

URK. Not the best resolution in the photo, but from the looks of your improvised valve bucket compression tool, I'm naming you an Honorary American. That's some Yankee Ingenuity right there, if ever there was.

You might be onto the source of your noise. A shim needs to be nice and smooth and sharp-edged; they form an "hydraulic lock" with the top of the bucket via the oil film that's squeezed between. A torn-up shim could very well be "bouncing" in and out of its bucket when the motor's running; if that were the case, it would cause a terrible racket. I don't think it could "spit" since the clearance is too tight.

I think you could very well have stumbled upon evidence of "the "poor man's shim pool", israeli style." I too think he simply gave up after butchering that one; let's hope so.

Take a close look at that particular bucket let's be sure it hasn't been torn up too.

You need to check them all. Have you figured out what we generally refer to as the "zip tie trick?" Don't use a zip-tie, use a foot-long piece of insulated #12 house wire (solid wire not stranded.) The wire gets a small "J" bent into one end of it. You slip the wire down the spark plug hole, and "hook" the end of the "J" into the valve seat when the valve is open; as the motor rotates and the cam lifts away from the shim/bucket, the valve is held open by the piece of wire so the shim/bucket doesn't come back up and you can pluck the shim that way.

Is the idea clear, or do I need to explain it better?

Oh, and PS: "Terminology check:" Admission=intake; you have intake valves and exhaust valves.

Once you check them all, we can figure out what size shims you need; I'm reasonably sure your bike takes the same shims as a lot of other Yamahas so finding them shouldn't be too difficult even in your part of the world.

 

Time to start a shim pool in Israel

 

The Yankee Spirit: "where there is a will, there is a way"

URK. …. from the looks of your improvised valve bucket compression tool, I'm naming you an Honorary American. That's some Yankee Ingenuity right there, if ever there was.

>>> I feel honored by the nomination. Thanks, BF!

this concoction however came out of a misunderstanding! After seeing your picture of “the tool” (hidden by the cam), your references to “inserting the tool’s wedge”, and the manual illustration (IOY Markie) of a different model, I got the wrong idea that the 12 gauge wire would be used as a kind of outer rim holding that inverted cup down. Now I see how dead wrong I was.
I think this is the first time you tell me the hook goes into the sparkplug hole. The surgery parallel almost drove me sick – it is like operating prostates… yukkk!!!!
Could you please take a picture of “the tool” so that I can figure out how it works? The drawing shows how I imagined it. Gross...Since the manual says the shims must be checked every 26,000 Km, and I intend to keep this XJ400 AND to be my own mechanic from now on, I guess I should order one right away, perhaps along with the new shims! Oh, and I want to learn how do I fish shims from a shim pool!

 

Aharon. The manual I was looking at was the XJ600 diversion - the same as the XJ400 diversion. The picture of the tool that you has posted is correct for your model.
Check the manual again.
The tool consists of a semi circular hook which has an arm. The hook sits under the camshaft and the bottom of the semi circle presses down onto the valve lifter when you apply pressure to the arm.
By putting pressure on the valve lifter, it allows the shim to be withdrawn.

 

Let me clarify something; it's my fault.

There are two completely different methods of accomplishing basically the same thing; I'm afraid you've misunderstood them to be one and the same.

The proper tool is the one pictured at the top of page 4 of this thread, the pic you posted on Nov. 13. That's what Markie's talking about, and it is the correct and easier way to do it.

-OR-

The improvised solution I was referring to involves sticking something (a piece of wire) in the way of the valve closing all the way, and "holding it open" from below. This is not the "correct" way to do it, but it will work if you don't have the correct tool.

If you can get ahold of the correct tool, I would very much recommend doing it that way.

 

Re: XJ 400 - "The Tool" made in Israel

Only the need to take the missus to the supermarket prevented me from checking if "the tool" israeli-style works! So, tomorrow it is.
For the equivalent to USD39, I had this ready two hours after I ordered it. Arguably cheaper than ordering over, less the wait...
After my "yankee creativity" before, I am sure it will work all right!

 

Wowzas. That does appear to be a pretty darn decent approximation of the real thing (having never seen one in person myself either.)

 

Re: XJ 400 - Shims readout

Well, these are the values of my [gaps - shims]:

front of bike
[0.15 - 270] [0.15 - 265] [0.15 - 270] [0.15 - 270] (right side)

[0.12 - filed out] [0.10 - filed out] [0.05 - 270] [0.05 - 270]

The clearances according to the XJ600 manual are:
admission (intake?) - 0.11 to 0.15
escape (exhaust?) - 0.21 to 0.25

Please let me know which shims I need to purchase, and who is the "shim-pool master" :lol:

"The Tool" - You do NOT want to make your tool out of aluminum. The camsahft surface is rough, and grinds out a lot of material.

 

I have one question for you, and then I'll get after helping you figure out which shims you need.

What DIAMETER are your shims? I suspect they may not be the same as the earlier XJ series (although they are common to a lot of Yamahas if they match the 600 Divvy.)

 

I will check it out, bigfitz. Meanwhile, I want to wish you and all my good friends here a wonderful, merry christmas!

 

The diameter is 25mm, BigFitz.

When guessing the replacement shims, please refer to my previous e-mail from Dec. 24: exhaust shim #2 is 265, while all the others are 270.
The four exhaust gaps are the same: 0.15mm, which baffles me - if all valves have done the same amount of work since the bike sprang to life, how could one seat wear more than the other three? :?
It seems that every time we face up and weepingly cry "why", all we get is a thunderlike "BECAUSE" from above. And consider yourself very very lucky if that is all you hear, and not a demeaning "because, you faggot"! :lol:

 

Thank you. That's what I thought; the older XJs use a 29mm diameter shim. Fret not, apparently the 25mm diameter shim is common even among some current and very recent Yamahas.

You're under a misconception in regard to the shims, their sizes, and wear:

We replace them to compensate for wear, but not the wear of the shims themselves; the valves pound themselves into their seats which causes the clearances to tighten up.

This wear is not always even, and that's not a cause for concern.

They didn't all start out with the same size shims in every cylinder; when I did my '83 550 it had never been touched, the shim sizes varied as much as two sizes each way from their neighbors, right from the factory. (And after 7100 miles, 7 of 8 were tight.)

And I'm not going to "guess" at which shims you need; I'll figure it out and then explain my math.

But it's Christmas and it's after 12:00 noon so I must now consume Holiday beer. I'll do the shim math another time soon.

Cheers!

 

Re: XJ 400 - Carburetor rubber hoses

I know my shims replacement is just the first step on a long journey...
To gain access to the shims, I had to loosen the carburetor set (to give way to the valve cover). And I noticed that the rubber tubings (hoses) are dried out and cracked.
They sell automotive tubings at stores, is it ok if I use it? (it seems that at least one rubber tubing in the XJ has a "Y" format - this would have to be ordered...).
I can only guess what will come later. New brake disks. Fuel pump? The list will be looooong!
Aharon

 

It's certainly OK to use automotive tubing for fuel, vent and vacuum lines, with one caution:

Be sure to use actual vacuum line to replace vacuum line, as conventional tubing may collapse in on itself under vacuum once warm.

 

Re: XJ 400 - Replacement shims sizes

Dear friends, out of pure anxiety, I did some (a lot of) thinking, and came out with the following measurements for the replacement shims for my bike. According to the manual, the gaps must be in the following range:
intake: 0.11 to 0.15
exhaust: 0.21 to 0.25

Exhaust valves 1 to 4:
Present gap: 0.15 (all four)
Target gap: 0.25
Present shim: 270
Replacement shim: 260?

Intake valves 1 and 2:
Present gap: 0.10 (both)
Target gap: 0.15
Present shim: 270
Replacement shim: 265?

Intake valves 3 and 4:
Present gap: 0.05 (both)
Target gap: 0.15
Present shim: 270
Replacement shim: 260?
Am I too far or close?

2- I intend to order (from the US) both the shims and air/ oil filters. I will buy a new battery here in Israel, and perhaps new spark plugs (I have not yet checked whether the existing ones are good or not). Do you recommend anything else to change right away, so I could get it all in one shipment?
Thank you, I hope your holidays season has been “metsuian” (excellent).
Aharon

 

Re: XJ 400 - Replacement shims sizes

[edit] the same post was displayed three times!

 

Re: XJ 400 - Replacement shims sizes

[edit] the same post was displayed three times!

 

Re: Shims-- I do believe you nailed it. Good job.

Re: #2: Remember your shims are the smaller 25mm diameter, not the 29mm like the earlier XJs. You might want a new valve cover gasket and the metal/rubber composite "donuts" that go on the valve cover bolts; otherwise you should be all set with what you listed, at least for now.

 

Thank you, BigFitz.
About this "shim pool" I've read you guys talking about - can you give some pointers as to whom I should address to help me out? "If" I got it right, I mean. Would Lem be that person?
Have a good one, dear friend!
Aharon

 

Anytime my friend; I think we're making good progress and I'm not giving up.

The "shim pool" you've heard referred to is for the 29mm-shim folks; although I'm sure somewhere there's a 25mm shim pool as well.

Myself, I belong to the "Don't Reuse Shims" camp. Why? Shims wear. They "wear in" to their cam lobe (the relationship is slightly angular, to cause the whole thing to randomly rotate; you can see it when you turn the motor over, the buckets rotate (the stupid notch moves on you.) I don't like the idea of putting a worn (slightly, agreed, but still worn) shim under a "strange" cam lobe. I'm in perpetual mid-life crisis mode so I tend to romp on my XJs. I don't even want to begin to contemplate the cost of repairing the damage from a spit shim at 9500rpm compared to the cost of a new shim. Cheap insurance or the old guy being anal? I asked my wallet, it said buy new shims.

Len (not Lem) (XJ4Ever, pm member chacal) carries new (29mm) shims for half of what Yamaha gets for them. You'll have to ask him about the 25mm shims, I don't honestly know if he carries them.

You did a good job on your shim selection.

Happy New Year from the frozen midwestern US.

 

Guys,
moto-services.net supplies for the 25mm diameter shims I need.
Their catalog is vast, and include the air and oil filters that I need (I intend to order the parts intended for the XJ600, of which the XJ400 seems to be a smaller sister:
https://www.moto-services.net/catalog/2 ... atalog.pdf
However, I could not find a set of "VALVE COVER GASKETS, BOLT SEALS" for the XJ600. Only for older 550 and 650...
Can you give me a hint of which to order? Would the XS400 gasket eventually do? Or is it a totally different animal?
Dang, the day I hear my engine roaring (or purring) cannot come any faster...
Aharon

 

Good find. I will peruse their catalog for you and try to help. (When my innanet speed picks back up a tad; it's snowing and we're "lagging.")

The "bolt seals" (donuts) for your bike are going to be different than those for the older XJs, unfortunately.

The valve cover gasket may be the same as the one for the XJ600 SecaII/Diversion of the same year as yours, but I have no way to confirm that.

Unfortunately, the XS400 is COMPLETELY different; it's a 400 twin. The XS400 Seca and Maxims have a "half an XJ" motor, DOHC, shim over bucket, CV carbs, the whole bit-- but only two cylinders. They never sold the 400cc-4 cylinder bikes in the North American market.

 

Thank you as always, BigFreeeend (non-desphikablllle type).
I would e-mail you the catalog... if the dastard did not weight 28MB! But it will be useless, see the reply I just got from Matthew, a nice chap @ moto-services:
"Yes as you noted the XJ400 was not a US model thus it is not listed in out catalog. I will not be able to get the Valve Cover Gasket but I may have the Bolt Seals (doughnuts) if you can provide the OEM Part number and/or direct me to a website that has the Yamaha Parts Fiche online so I can look at Yamaha part numbers for cross reference."
my vin is 4BP00.
But it is cool. I am making progress, and that is what counts.
It is cold here too (about 15C, you do the math to farenheit), there is perhaps 1/2 inch snow falling up in the Golan. Man, I love it in here, life is just fine among my Jewish brothers and sisters!
Have a good one!
Aharon

 

Aharon - follow this link to "Wemoto" - a UK company that stocks spares for the 600 cc version of your bike. http://www.wemoto.com/bikes/Yamaha/XJ_6 ... sket_Seal/

They export spares and you wil pay 20% less than the list price as you are outside Europe.

You will need to find if the 400 and 600 gaskets are the same size.

 

The bolt seals should be the same as the XJ600 Seca II/Diversion. That number is 4BR-1111G-09-00 (Supersede: 5EA-1111G-00-00.)

As for the gasket itself, what we need to find out is if your valve cover is the same/same size as the one for the 600.

How about post a new thread asking '90s XJ600/Seca II or Diversion owners if someone can measure the overall width of their valve cover, and see how it compares to yours off the 400? We know they look alike and are the same shape; if they're the same width it's almost for sure the same.

Unfortunately, since the later 400-4 wasn't sold in Europe either, we're still up against whether things are the same-same as the 600, or just look the same.

One other thing; you might want to go ahead and get a set of exhaust pipe-to-head gaskets, as that will be our next challenge. I'm willing to bet that THOSE at least will be the same as about half the Yamahas on the planet, pn 4H7-14613-00-00 (from the 550 Seca) cross-references to EIGHT PAGES of Yamahas, from 80cc singles to the XJ750 and to a superseded "4BR" number; since the Seca II-600 has "4BR" numbers all over it, I think that one's a safe bet.

 

Thank you BigFitz and Markie.
Nice you remembered my next challenge, the exhaust pipes, I will certainly purchase the gaskets. Speaking of which, you remember the picture showing a deep moss in one pipe. Any ideas about repairing it? Perhaps cut and weld the damaged lenght?

 

Re: XJ 400 - Ordering Parts...

I checked wemoto.com;
To make my question simpler, can you tell me where I find the part numbers for the XJ600? (there are two series - one is 91-92, and the other is 92-95 I guess).
If I have it, I can look for:
- camshaft cover gasket and seals
- air filter
- oil filter
- exhaust pipe-to-head gaskets
- yamaha shim tool (like BigFitz's, see figure).
Thank you!
Aharon

 

The bike that is most similar to yours is the '92-'95 series Seca II-600/Diversion. I've been using the '94 XJ600SF Seca II (USA market) fiche as my reference.

The shim tool for your bike is different, I believe. You posted a pic on Dec 9th (it's on page 4 of this thread) showing "the tool" for your style bike in use. The kind I used in the valve adjustment articles for the earlier bikes won't apply to yours, (I believe there's nowhere to bolt it to.)

Like I said before, I can't be 100% sure the actual valve cover gasket is the same; the valve cover could LOOK the same but be proportionally smaller. The other stuff should "cross" however.

As for the exhaust pipe, the cutting and welding idea probably won't work. These bikes have double-walled pipes; if the inner pipe isn't too badly dented it will be OK, if the inner pipe is smushed (or broken up, which isn't uncommon) then replacement is likely the only option.

Unfortunately, if your bike is the same as the 600, the exhaust head pipes are part of two assemblies, one consisting of pipes #1 and #4, one of pipes #2 and #3.

CLOSELY EXAMINE the exhaust system for me if you would; Yamaha liked to stamp part numbers into their exhaust parts. Usually in an out-of-the-way but relatively accessible spot. I'll bet anything you'll find various part numbers. Report back what you find. We'll explore options.

 

Re: XJ 400 - Ordering Parts...

The 91-92 model IS the bike I owned - called a "Pre-diversion". It is very close to the XJ550. The old XJ600 was sold in the UK until 91-92. You will need the later model. The Early parts WILL NOT FIT. The bike yours is closest to is the XJ600s or n. One had a fairing "S" and one was naked "N".

 

I cannot believe I was finally able to place my order for my shims!
Because my Visa was Brazilian and the delivery address was in Israel, I had to apply for an Israeli one, then add it to paypal, then validate the bugger... and deal with a website in Hebrew! Holy dang!!!
But it's all for the best, right-o? Hopefully I will have my stuff delivered to me quick, 'cause I can't wait to hear my motor running!
Hope to get good news soon, guys!

 

Hi guys, long time no see!
I finally got my shims and camshaft cover gasket from wemoto.co.uk (they call it "rocker cover", he!).
Here is the "question du jour":
before closing the cover, do I apply any kind of "goo" (3M or similar) to the gasket? which brand/ name?
On top and bottom?
How much torque on the cover bolts?
Thank you!
Aharon

 

Gotta love that, this motor has no "rockers."

"Glue" the gasket to the cover with a gasket sealer of your choice. I use a spray type, sprayed into a small cup and applied with a paintbrush. You can use a smear of Permatex or even Elmer's Glue. Let it set up.

Then smear the other side of the gasket with grease (silicone or chassis) or even lightly oil it before installation.

This way it can easily be removed and reinstalled many times over without damage to the gasket.

Examine the bolts closely. If they have a "stop" built into them (and I suspect they probably do) then they only get tightened to 7.2 ft/lb, like any other case/cover bolt. Check your manual to be sure.

(Be sure the front cam chain guide is in its notches before installing the cover.)

 

Come to think of it, it really doesn't! a-ha!
thanks, BigFitz.
But I confess: now that the moment of truth nears, I-Am-Nervous!
Aharon

 

I ordered the Yamaha-suzuki shim tool off e-bay. My "fake" tool (made of aluminum) is too cumbersome for the job.
Guess: $14,80 for the tool and $29 s&h - but it is worthy.
"Let the tool do the job" was the motto of Popular Mechanics back in the 50's and 60's.
I got most of my English vocabulary reading it and Mad Magazine. Don't laugh! Mad used to have some great writers!
Hope to have good news soon, folks!
Aharon

 

Hey I'm a big fan of Popular Mechanics, Popular Science AND Mad Magazine! "What, me worry?"

"Google Books" has back issues of PS and PM; I love the ones from the 40's. Read October 1941 Popular Science for a kick. I found an ad for Vice-Grips in a 1940 issue of Popular Mechanics.

Glad you checked in.