Timing Advance

On Saturday, I reinstalled the cam cover on my KZ440B1 and started the bike, which ran a bit ragged but ran and responded to throttle. On Sunday, thinking I'd go test it on the street before screwing with carb settings I went through the previous day's work, which included checking the valve adjustments. I've done this numerous times.

I did the right side check, but while rotating the crank to TDC in order to check the left side valves, I heard an odd sort of ratcheting noise and "thought" that I saw the the timing advance slip backward (clockwise) from the corner of my eye (I wasn't actually looking through the window in the breaker plate - but it sure seemed like it moved).

The bike now will not start or even act like it might like to. I've been through all of the usual stuff. The timing is correct as best I can tell with a static check. Everything is plugged in and the coil windings test good with an ohmeter (I don't own a coil tester per se). The engine is receiving fuel and the float levels are pefect using the clear line test. I've tried new plugs.

Now, I know that the engine is heavily carboned, but it was running only 8 hours earlier.

So, did I do something dumb to the timining advance mechanism? Is it possible that whatever happened down there would keep the bike from firing at all? The springs appear to be in place, but I haven't yet pulled the timing plate off to look. I have looked at the timing advance in the last couple of months although I did not remove it and re-grease the cam. Everything moved correctly and, as I said, the bike ran.

If it is possible that the timing advance mechanism is the culprit, I'll go check on it. But, when I do that, what am I looking for that would indicate a problem other than a broken spring?

Long story. Thanks for listening and for any advice that you might have to give.

Hook up a strobe timing light and see if you actually have a spark taking place inside your engine when cranking. The simplest test you can do. If the light flashes, you have spark and can check the timing. No flashes = no spak = dead engine, and you need to find the source.

faffi wrote: Hook up a strobe timing light and see if you actually have a spark taking place inside your engine when cranking. The simplest test you can do. If the light flashes, you have spark and can check the timing. No flashes = no spak = dead engine, and you need to find the source.

OK. Hook the strobe to what, exactly? Like I normally would to check dynamic timing?

When rotating the crank to TDC or whatever, you should use the larger 17 mm. outer bolt rather than the smaller 13 mm. inner bolt. I am talking about the far right side of the crankshaft, which is right above the points plate or electronic pickup? If the inner bolt is used, there is the risk of twisting the bolt off, or perhaps it rotates the part that holds the weights and ignition cam. I am not sure what exactly goes wrong, but the service manuals warn against using the smaller bolt.

Anyway, this is my thought as to what may have happened. I am not sure how to correct this if that is the case. Perhaps someone else can explain it.

WABBMW wrote: When rotating the crank to TDC or whatever, you should use the larger 17 mm. outer bolt rather than the smaller 13 mm. inner bolt. I am talking about the far right side of the crankshaft, which is right above the points plate or electronic pickup? If the inner bolt is used, there is the risk of twisting the bolt off, or perhaps it rotates the part that holds the weights and ignition cam. I am not sure what exactly goes wrong, but the service manuals warn against using the smaller bolt.

Anyway, this is my thought as to what may have happened. I am not sure how to correct this if that is the case. Perhaps someone else can explain it.

I did indeed use a 17mm wrench, as instructed by the sevice manual.

I would confirm correct cam timing first - then re-asses your valve gap settings.
Pull advancer unit and ignition plate. Reinstall everything as per spec and set basic timing.
Afterwards perform a compression check to assure proper operation.
Check for spark while starting and make sure to keep battery topped up 12.6 VDC off.

Go from there...

That ratcheting sound can be cam timing getting altered if you happen to turn the crank the wrong way and the chain tensioner is not tensioned correctly.

Kawasaki shows the 81 440 B is a B2. So your bike is likely a 1980 B1, or 1981 B2. From the parts diagram, it appears to be a manual tensioner. Did you adjust that before doing the valve adjustments? The crank turns in the opposite direction from the wheels on the 400/440/750 twins, so that is the only way you should turn the crank, especially when doing camchain-tensioner work.

As Tek9ine said, I would recheck the valve timing first. Do not force the crank to turn if it seems to get stuck.

(I realize you may already know some of what I'm posting, but just posting it to be sure.)

loudhvx wrote: That ratcheting sound can be cam timing getting altered if you happen to turn the crank the wrong way and the chain tensioner is not tensioned correctly.

Kawasaki shows the 81 440 B is a B2. So your bike is likely a 1980 B1, or 1981 B2. From the parts diagram, it appears to be a manual tensioner. Did you adjust that before doing the valve adjustments? The crank turns in the opposite direction from the wheels on the 400/440/750 twins, so that is the only way you should turn the crank, especially when doing camchain-tensioner work.

As Tek9ine said, I would recheck the valve timing first. Do not force the crank to turn if it seems to get stuck.

(I realize you may already know some of what I'm posting, but just posting it to be sure.)

Yes, it's a 1980 B1 (points and drum brake), and no, I didn't adjust the cam chain tension before checking valve gaps. So, I'm pretty sure that what you describe is EXACTLY what happened. I really tried to be careful with that counterclockwise only rule but was using a ratcheting 17mm wrench. It never dawned on me that the ratcheting mechanism would produce enough torque to actually turn the crank, but it must have. My problem now is that I'm not at all sure how to undo it.

Back to the service manual and thanks to you and Tek9ine for your advice.

You may want to update your signature to reflect that it is a 1980 (I assume that the bike in question is the one in your signature).

It's possible the previous owner has never adjusted the tensioner, which would explain why the chain so easily jumped a tooth.

However, in my experience, cam chains don't easliy jump a tooth unless the cover is off or some other chain guide is missing or broken. If this happened while the valve cover was off, that would explain it.

I'll have to look back at your original post (which I can't see as I type this).

EDIT: So it looks like your valve cover was on when you heard the ratchet noise. But it is possible the cam chain jumped before you put the valve cover on, and then the noise you heard was the slack re-adjusting itself to the tensioner side of the motor (front).

At any rate, you'll have to check the manual to make sure the cam timing is correct.

Another thing you may want to do, is make sure the advancer's T mark is actually at top-dead-center. Take out one spark plug and put a screw driver into the hole so that it goes up and down with the piston. Then rotate the crank so that it is near TDC. Rotate it so the screwdriver just stops moving up. Note where the advance mark is. After the screwdriver starts moving down, reverse the crank until the screwdriver once again stops moving up. Note where the crank is. The center of the two positions should be TDC, and that is when the T mark should line up. You have to do this multiple times to make sure you have it right. You shouldn't have to rock the crank back and forth more than a couple degrees to find the center.

You can rock the crank back and forth a couple degrees near TDC and it should be safe. It is only large swings in the reverse direction than may cause issues with camchain jumping.

loudhvx wrote: You may want to update your signature to reflect that it is a 1980 (I assume that the bike in question is the one in your signature).

It's possible the previous owner has never adjusted the tensioner, which would explain why the chain so easily jumped a tooth.

However, in my experience, cam chains don't easliy jump a tooth unless the cover is off or some other chain guide is missing or broken. If this happened while the valve cover was off, that would explain it.

I'll have to look back at your original post (which I can't see as I type this).

According to the service manual, the cam chain tensioner on this thing is "automatic" and no adjustment is required. However, I've been reading some posts that suggest that removing it and reinstalling it solves apparent cam chain problems. Of course, I'll have to do that if the cam timing is off.

I should be able to adjust the cam timing without actually removing the cam, right? It looks like f I remove the cam chain tensioner as directed by the manual, the chain should be loose enough for me to reallign the cam without actually removing it or the sprocket.

Oh, and I did update my signature. It seems that this bike was titled as a 1981 in Nebraska. It took a while for me to figure out that it was in fact an '80 based on the VIN and I never got around to changing my profile. I'm guessing that it came into the country late in '80 or maybe in '81, even though it was an '80 model.

I was able to locate my factory 440 manual (on pdf). If you want a copy of it for online use, let me know.

Yes, you are correct it seems to be automatic.

You usually don't have to remove the cam shaft to change cam timing, but sometimes you have to remove the sprocket from the cam in order to get enough slack (in addition to removing the tensioner).

On my KZ550's, it is very difficult to walk the chain over the sprockets to alter the timing unless you unbolt the sprocket from the camshaft. On the 550, after you unbolt the sprocket, it will slide off the mounting hub and move to the smaller-diameter portion of the camshaft. This gives a lot more slack and freedom of movement to the chain and sprocket, making it easy to walk the chain to a new position.

But a 550 is a different beast from a 440. I'm not sure how it is on the 440. If you're lucky, simply releasing the tension on the tensioner may get you enough slack to walk the chain (if, in fact, you need to do that).

I read a warning on the tensioner, though, that you should not remove the tensioner partially, then try to re-install it. It must be removed completely before re-installing or you will have too much tension on the chain.

I haven't looked up the process in the manual for the 440 yet. I'll look at it a little later.