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Discussion Starter · #1 ·
I know nothing about motors but my mechanic went under so I have no choice but to learn for myself. I have another motor related question? Is there a specific order to do a proper valve adjustment. I have a Clymer's repair/service handbook but it seems to explains things to someone who knows what they're doing. I need a repair manual for dummies right now.

Thanks, Matt
 

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NE350 said:
I know nothing about motors but my mechanic went under so I have no choice but to learn for myself. I have another motor related question? Is there a specific order to do a proper valve adjustment. I have a Clymer's repair/service handbook but it seems to explains things to someone who knows what they're doing. I need a repair manual for dummies right now.

Thanks, Matt
The sequence of which one is done first doesn't matter but they should be done cold. Now, with that said, Bill has documented some very nice instructions on how to do the 350 valves with the motor running. I recently tried the technique and it works great! You have to know what you're listening for and you have to understand what the motor is doing when you make the adjustment but it's so much faster and easier than messing around with the feeler guages.

If you were uncertain you could always adjusts them while the motor is running then shut things down and verify the accuracy with a feeler guage. If it was my first rodeo, I'd probably do that as part of the learning experience. The ex valves on the 350 are easy enough with the feeler guage but the intakes can be a little difficult to get to if you're inexperienced. I've done tons of valve adjustments on Chevy, Ford and Mopars and we always did them with the engine running. We always used a feeler guage during that process but the 'listening to the motor' technique works just as well.
 

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Discussion Starter · #3 ·
Thanks again Mike. Since the motor is not in the bike yet, maybe I'll wait for Bill to chime in with his detailed instructions.
I'm busy with work for the next two weeks, then i'm off to enjoy some of your FLORIDA sun. My parents retired to Venice.

Matt
 

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NE350 said:
Thanks again Mike. Since the motor is not in the bike yet, maybe I'll wait for Bill to chime in with his detailed instructions.
I'm busy with work for the next two weeks, then i'm off to enjoy some of your FLORIDA sun. My parents retired to Venice.

Matt
I was just searching around for the instructions but I didn't find them.

Since the motor is out of the bike it would be very easy to use the feeler guage and you should do that. You want to have the valve adjustment pretty close before you first start the bike and it's easy to do with the motor out of the bike. Just follow the instructions in the manual and ask some questions here if necessary.
 

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Discussion Starter · #6 ·
OK, the inlet valves were dead on at .002. The exhaust valves are a different story though. It says they should be .004, however there is .000 between the two. I loosened the lock nut and turned the adjusting screw. As I did the valve stem went up but at the apex it did not lift from the tapet. What next?????

Matt
 

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Matt, it doesnt sound like you had the piston in the right position and it was on the exhaust stroke which would have been opening the valve.
No harm done. But you will need to make sure you have the piston of the valves that you are adjusting at top dead center ( TDC ) so that both valves are closed ( rocker arms loose ) before you adjust them. You also need to set one cylinders valves at TDC and then rotate the engine to put the other at TDC before adjusting that one.
Do you think that is what might have happened?
Don
 

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Discussion Starter · #8 ·
Don,

I may have. I was a little confussed about which side was left or right, since my motor is out of the bike. I rotated the generator to the LT mark, removed the tappet covers and stuck my feeler gauge in and got the .000. I'll give it another shot, it was late when I was trying to figure it all out.

Matt
 

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Matt -

It needs to be done at TDC on compression stroke.
Stick your finger in the spark plug hole and turn the alternator counter-clockwise.
As the piston comes up on compression stroke, you'll feel/hear the air being forced out through the spark plug hole.
Bring it up to the "LT" mark, figure out how to keep it there, set your left valves and left ignition timing (with a little bulb). The "F" marks are here anyway, time it now.
Then rotate the alternator 180 degrees (CCW) - half a full turn.
Line up the "T" mark, set the right side tappets, right side point/timing.

Tappets should always be adjusted when the engine is stone-cold.

Then adjust the cam chain, as outlined in the manual.

Here are the two Honda manuals I have - both contain certain errors or omissions, but way better than the Clymer.

http://home.comcast.net/~tbpmusic3/CB_CL_SL_250_350.pdf

http://home.comcast.net/~tbpmusic3/CB_CL250_350RepairManual.pdf
 

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Discussion Starter · #10 ·
dlslick said:
Matt, it doesnt sound like you had the piston in the right position and it was on the exhaust stroke which would have been opening the valve.
No harm done. But you will need to make sure you have the piston of the valves that you are adjusting at top dead center ( TDC ) so that both valves are closed ( rocker arms loose ) before you adjust them. You also need to set one cylinders valves at TDC and then rotate the engine to put the other at TDC before adjusting that one.
Do you think that is what might have happened?
Don
Don, That is exactly what happened. Thanks to Bill I read through the manual a few times before it sunk in. I even checked points and ignition timing. I think I did it fairly accurately, well see when I fire it up :)

Thanks, Matt
 

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I think i may have removed or deleted the post on adjusting 350 tappets with the engine running.

It's really something I would only recommend to very experienced mechanics who've done a lot of 350's......
 

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I'm pretty new to this and trying to figure it out on my '72 350. A few kinda dumb questions here, so bear with me..

In order to adjust the intake valves, I'll need to remove the gas tank, correct? The intake valves are towards the rear by the carbs, and the exhaust valves are at the front of the engine by the headers?

Thanks!
 
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