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Discussion Starter · #1 ·
I wanted to re-check my cam chain tensioner bolt last night so I set the engine to TDC left side on the compression stroke. Backed the tensioner bolt out 1.5-2 rotations (probably less) tapped a bit and tightened.



How tight does this bolt need to be? I know 4-6lbs, but damn. Even after rotating 2x it seems too easy to make another rotation. I really don't think the bolt is backed out all the way, but the only way for my to sleep well at night will probably be to pull the damn thing and pop this rear cover off. Shouldn't take me more than 3-4 hours at this point.
 

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Even though you dont tighten it up much, you should feel it come to a definite stop as the flat on the base of the bolt comes into contact with the casing
 

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Discussion Starter · #3 ·
I have a feeling this rear case is coming back off then. It definitely doesn't feel like that. Damn it! I hope I can reuse my rear case gasket. The good part is I need to remove the flywheel/starter clutch to get to that bolt.



Should actually be a pretty easy job.
 

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Phil, why do you need to remove the flywheel? The cam adjuster bolt is above the flywheel. Otherwise it wouldn't be sticking through the back cover.



As for tightening the bolt, I tightened mine years ago when I did my first rebuild for the red CX500. A couple years later I removed the cover to do the mechanical seal again. I found that what I had done by over tightening the cam adjuster bolt was to flatten the soft steel of the adjuster. What it did was to spread the steel out to the point where the slot that the bolt rides in got narrower. By doing this it didn't allow the adjuster to move when I loosened the bolt to do an adjustment. I had to file out the slot again so it would free it up and let it slide freely again. So be careful not to exceed the specs. You'll always think your adjusting the chain when in fact it's just staying in the same spot.
 

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Phil

these bolts can and do strip but can be helicoiled. Knowing honda cam chain tensioners of old theres one addition I always make and thats an extra 7x13 spacer, which I cobble from another old scrap motor. Thats the one that goes in the front post of the tensioner arm. I fit a second one to the open end of the arm (the one secured by the pin). I do this because you notice over time that the thread the tensioner bolt screws into gets looser as the tensioner arm bends around and feeds torque back through the assembly to be a constant niggling little twisting force on the bolt, and this is common to a lot of honda's that use this type of tensioner. If you measure the thread drop ( ie loose bolt in the thread, then "push" it until it takes up the slack in the 3, 6, 9, and 12 oclock positions you see there is more wear at 6 and 12 oclock, not 9 and 3 as it should be because of the way the arm pulls. this also means that the front of the arm can not twist ( most of the cause of sticking so once you loosen the bolt, it pretty much tensions immediately, rarely requiring the otherwise obligatory mallet taps



anyway, hope your fix is simple and that its not stripped
 

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Discussion Starter · #6 ·
Phil, why do you need to remove the flywheel? The cam adjuster bolt is above the flywheel. Otherwise it wouldn't be sticking through the back cover.



As for tightening the bolt, I tightened mine years ago when I did my first rebuild for the red CX500. A couple years later I removed the cover to do the mechanical seal again. I found that what I had done by over tightening the cam adjuster bolt was to flatten the soft steel of the adjuster. What it did was to spread the steel out to the point where the slot that the bolt rides in got narrower. By doing this it didn't allow the adjuster to move when I loosened the bolt to do an adjustment. I had to file out the slot again so it would free it up and let it slide freely again. So be careful not to exceed the specs. You'll always think your adjusting the chain when in fact it's just staying in the same spot.


Sorry, I meant I didnt have to remove. Your experience sounds like what I am experiencing. :/
 

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It will not come out the back cover. There is a wider collar base on the bolt that is bigger than the hole in the case. If you kept turning it out I'm sure it would break the rear cover.
 

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Discussion Starter · #9 ·
It will not come out the back cover. There is a wider collar base on the bolt that is bigger than the hole in the case. If you kept turning it out I'm sure it would break the rear cover.


Right right, I remember a post about that. Either way, I did't back it out more than 2 turns, and when tightening it still SEEMS loose to me, I could be crazy (as stated before
)
 

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It may have been overtightened in the past and partially started to strip the threads out.

You may be able to look into the inspection hole while its idling to see if it's bouncing around. Otherwise I would pull it apart if your that uneasy about it.
 

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Discussion Starter · #14 ·
Replying to my own thread here. I have listened to a few other youtube videos of cx's with bad cam chains, and it seems that my noise is more of a tappet noise, which would make sense because I replaced the chain.



anyone wanna chime in?



Just listened to it again, gotta be tappets.
 

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ChimChimChim....


I have to agree with you. It does sound like tappets. But if you already adjusted them, I have another idea for you. The shaft that the rocker arms ride on wear badly on the push rod side. If your adjusting the valves one valve at a time then your going to end up with 2 different settings on the same side. I'm going to have to explain later though. I'm just about to do some painting and I need to get it done before the sun goes down. So I'll get back to you in an hour or so ok.
 

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OK, I posted about this a long time ago on the old forum. But it didn't seem to sink in to anyone that has not had me do this procedure for them. Then they believe because they can hear the difference.



Now stop and think about the valve train and the rocker assemblies. On ONE side there is a push rod that opens and closes the valves. Imagine if you had a 4' board, and you rested it on a rock 1' from the end and started rocking it up and down for a couple years. Where it is pivoting on the rock it's going to wear out a groove in the board right! Well, that's the same thing that's happening in the rocker arm and the shaft. The end closest to the push rod has to carry the full load of the force. Because of that, it wears the shaft much more on that side.

See the end of the shaft here? It's worn deeper than the other end.





Now, if you adjust each valve separately, then one of them is going to be looser than the other because of the slack. See, when you put the feeler gauge under the valve closest to the push rod, it's going to take up the slop in the shaft first and then you get your adjustment. Then you do the other valve and adjust it. I bet you think you have both valves even now don't you. OK test it! No, don't start it! Test it by using the feller gauge under BOTH valves at the same time.





With it under both valves, use one finger and slide the feeler gauge out. If you were right, and the valves were adjusted properly then it should slide out evenly on both sides right! I'll bet you a dollar it doesn't!

In order to get the adjustment even under both valves you need to adjust the valve farthest away from the push rod first. Get it a bit on the snug side but not so snug that you can't slide the gauge back in when it's been pulled out all the way. Lock it down. Now for the fun part. LEAVE that end under the valve and slide the other end under the other valve and do your adjustment so it matches exactly the resistance of the first valve.

Here is a tip; If you tighten the second valve too much, the other end will slide out with no resistance because you raised it up off the valve by over tightening the second valve. THAT'S HOW YOU GET NOISY VALVES EVEN AFTER YOU DID AN ADJUSTMENT ALREADY!

The trick here is to leave the first valve adjusted and adjust the second valve until it matches perfectly. By that I mean that you should be able to slide the feeler gauge out EVENLY from the center. It may take a few tries to get this down but trust me it's worth it.





NOW if you are going to be taking your heads off at any time remember this tip. Pull both rocker shafts out and swap them to the other side. When you do this it rotates the shaft 180 degrees and gives you a smooth fresh surface to ride on. This will even out your rockers IF the rocker bushings aren't so worn out that it wouldn't make a difference.

The picture below is the same worn out shaft that's pictured above. It's just swapped to the other side and rotated 180 degrees so the rocker rides on the new surface and the notch lines up for the head bolt. This way the adjustments are as even as possible.





I hope this long winded reply makes sense to you. I have used this on several motors including motors for guys from this forum. All of them sound and run a little better as well as put a smile on the owners face.



Larry
 

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Discussion Starter · #18 ·
Larry



Much appreciated, I'll be following these instructions tomorrow along with dressing the tappets via Sheps method. Once complete I will report back. One thing though, Stitch's post on the old forum has a feeler gauge that looks a lot thicker than what I am using:



 

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Phil,

That picture is one that I sent Don. I grabbed any gauge laying in the drawer just to show Don what I was talking about at the time. Yes it's a lot thicker. Sorry!
 
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