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Discussion Starter #1
Does anyone have any idea of how much clearance there should be between the valve cover and the camshaft chain on any of the kawi 4 cylinder engines?
The reason I ask is because I have a 1984 ZN-1100 and if I install the valve cover WITHOUT the gasket, the cover will hit the camshaft chain. I will of course use a gasket when it comes time for final assembly, but I am concerned that maybe my bike has the wrong valve cover. What actually touches is the rubbing block that is bonded to the valve cover. It does not touch by much, but the cover rocks back and forth and given that the gasket is probably only 1/8 of an inch thick, the clearances are very tight. Is this intentional?
 

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If the top camchain guide is in the valve cover, then you would have to loosen the camchain tensioner, pull hard the chain on top to force the intake camshaft to turn a bit, and create a sag between the sprockets. When you place the valve cover over the head, it should rest flat on the head, not on the chain....even the factory manual would not tell about these basics.

This is what happens; I believe you have a crosswedge camchain automatic tensioner. The tensioner moves forward to takeup the slack, the cross wedge prevents it from retracting. If you took off the valve cover, there would have been a sag between sprocket. If you move the cranshaft by hand, the automatic tensioner would take up the slack vacated by the guide and chain would get taut.

If you bolt down the valve cover back under these circumstances, the camchain would get overtensioned.
loosen the tensioner, create the sag, place the valve cover and bolt it down, reinstall the tensioner back. It takes some to understand removal of the cross wedge tensioner, but that's another history.

Once everything is back, turn by hand the crankshaft at least two revolutions before running engine.

V
 

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Discussion Starter #3
Thanks Hugojose! This makes perfect sense and I noticed the chain was extremely tight and wondered why. I was setting the valve clearance so of course the crankshaft had to be turned by hand.
 

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Just to clarify, do NOT loosen the tensioner body bolts that attach the tensioner to the cylinder block. Remove the cross-wedge cap & cross-wedge; then reinstall the valve cover; the pushrod should then kind of reset itself; then reinstall the cross-wedge & cap. On my 81 KZ650-CSR I turn the crankshaft 1 full turn before re-installing the cross-wedge.
 

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Discussion Starter #6
I was just thinking about this major omission from the factory service manual. Since an overly tight camchain can lead to premature camchain failure, this is a pretty serious omission. This omission was probably dealt with by way of a Technical Service Bulletin, which got me to thinking....are these bulletins available to us? Does anyone know of a source for these bulletins?
 

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A parts list micro-fische sometimes will have supplemental data.
You can find the micro fische cards on EB & the library may have a fische reader.
The Kawasaki micro fische cards usually have the diagrams at the top & supplemental data at the bottom. Sometimes there are only 3 or 4 supplement pages, sometimes quite a few. I'd guess that some of the supplement stuff may be in later versions of a manual.

The 81 KZ650 Kawasaki FSM has a warning about loosening then re-tightening the tensioner body bolts. I'm not an expert on the automatic tensioners, but I have completely removed it & looked at it carefully. The two bugaboos as I see it is that (#1) you don't want the pushrod to over-extend itself which can then stretch the cam chain; and (#2) you don't want the pushrod to fall down into the engine >> my tensioner has a dog bolt that should keep the pushrod from doing that as the pushrod has a groove where the tip of the dog bolt fits. I still don't want to chance it, so with the cross-wedge removed AND the valve cover off, I will NOT turn the crankshaft. I remove the wedge, then reinstall the valve cover, then turn the crankshaft. I use Permatex ultra disk brake grease to lubricate the cross-wedge.
 

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Discussion Starter #8
In the 1970's I worked at a Kawasaki dealership and we would get Technical Service Bulletins in the mail printed on looseleaf and we would insert these into a binder. It sure would be nice if Kawi made all of these available, but my guess is they won't.

It sounds like my ZN has a similar tensioner to yours Martin. See below for what mine looks like.
41419
 

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You do.....all Kawasaki crosswedge automatic tensioners are same. It is only a plunger, two springs, and a crosswedge…..and a set bolt to keep the main plunger from springing out..

.. and in my opinion it works quite well in spite of what some people say, if one does not trash the bike. The problem is with the confine spaces, and working against a spring, is very tedious and slow to unscrew it out, and screw it back in, as one is working against a spring.

,,,precisely, because of ease of maintenance, I have changed to a manual one. This makes it a breeze doing the valves, and also reaching under carb #3 where I've been known to change jets without removing carbs from bike.
 

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There are at least 2 types of Kawasaki automatic tensioners: the cross-wedge type discussed here in this topic & the earlier ball-lock type. I don't know anything about the ball-lock tensioners.

WFO-KZ, since it has a cross-wedge, the ZN1100 tensioner is pretty much the same as the 81 KZ650-CSR. Physically it looks different, but it still operates on the same principle >> the cross-wedge allows the pushrod to move forward as the chain stretches from normal use, but it prevents the pushrod from moving backwards. So when the valve cover is off & you turn the crankshaft, the pushrod may move forward to take up the excess slack from turning the crankshaft with the valve cover off. Then when you reinstall the valve cover before removing the cross-wedge, tightening down the valve cover bolts causes the valve cover cam guide to push against the cam chain & it could get stretched.
 

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Discussion Starter #11
Understood and thanks to you Martin and Hugojose for your help. On a related topic do you guys use OEM gaskets for the valve cover? If not do you have any recommendations? I tried to buy OEM but after receiving two different, damaged gaskets I am not sure what to do. My Kawi dealer has ordered a third gasket but based on how they are packaged I am afraid it will also be damaged.

The Kawi packaging is not good in my opinion. Picture one layer of thin carboard (like cereal box thin). The gasket is placed on top of the thin cardboard and is then covered with an ultra-thin layer of clear plastic that looks and feels like a shopping store bag. This offers no protection and the gaskets have arrived with deep dents, gashes, scratches etc.
When paying almost $50 for a gasket, I would like it to be undamaged but to get that I may have to buy from a third party and am looking for an supplier.
 

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Does anyone have any idea of how much clearance there should be between the valve cover and the camshaft chain on any of the kawi 4 cylinder engines?
The reason I ask is because I have a 1984 ZN-1100 and if I install the valve cover WITHOUT the gasket, the cover will hit the camshaft chain. I will of course use a gasket when it comes time for final assembly, but I am concerned that maybe my bike has the wrong valve cover. What actually touches is the rubbing block that is bonded to the valve cover. It does not touch by much, but the cover rocks back and forth and given that the gasket is probably only 1/8 of an inch thick, the clearances are very tight. Is this intentional?
I dont think you can get a valve cover to fit a motor it is not made for
 

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WFO, I don't know exactly about your bike. I own a '90 Zephyr, which was continuation of the '78 KZ750, same engine. In general the OEM parts are best and they tend to be best quality. Am surprised you are getting those from the dealer. I quit getting things from dealer many years ago, and get part like from Partzilla, RonAyers, and BikeBandit, they sell OEM or aftermarket. Z1 Enterprises is more specialized about old bikes and has good quality aftermarket parts.

About the valve cover. Mine uses a OEM mostly graphite. It is very good sealing, and expensive about $40.00, but after a few years opening valve cover, it tends to disintegrate and is not reusable. I since switched to a cover from the UK on Ebay., aftermarket, and it is less than 1/2 price and reusable. I applied graphite on it. But even though our engines are similar, they are not exactly same arquitecture and heads are different.

I would redirect you to a more specialized forums for KZ, your bike is a KZ in spite of the name; KZriders.com...other riders with same bike of yours would know better than I.

Valve cover gaskets are not really big deal, as there is not pressure there, they are merely splash covers.
 

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I was responding to a question about if incorrect valve cover may have been installed. But there is pressure in the motor. The 650 liked to blow out the gaskets if torque was not very correct. My Z1 and KZ it dont matter.
 
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