Valve adjustment


Valve adjustment

Postby ajs350 » Thu Dec 30, 2010 1:34 pm

I'm about to tackle the next task on my 80 which is valve adjustment and need some help.

First, The manual says that once the valve lifter holder is in place to "Rotate the crankshaft one full turn in the proper direction". The picture on page 3-11 shows arrows going in both directions so what is the "proper" direction?

Second, I've read comments about whether to use the Honda method of measuring valve clearences or a method proposed by Mike Nixon. What is Mike's method and is there really a difference?
Thanks
Ross
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Re: Valve adjustment

Postby SanDogDewey » Thu Dec 30, 2010 1:44 pm

Check CBXPRESS Summer 1990, pg 14 for Mike's method.
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Re: Valve adjustment

Postby ajs350 » Thu Dec 30, 2010 2:09 pm

SanDog. Is there a way to view past CBXPRESS articles on line? I looked through the forum but could not see a link. Thanks.
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Re: Valve adjustment

Postby SanDogDewey » Thu Dec 30, 2010 2:40 pm

Click Board index, under DIRECTORS, MEMBERSHIP QUESTIONS, CLUB NEWS & QUESTIONS go to ICOA CLUB NEWS. You'll see the link.
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Re: Valve adjustment

Postby EMS » Thu Dec 30, 2010 2:48 pm

ajs350 wrote:
"Rotate the crankshaft one full turn in the proper direction". The picture on page 3-11 shows arrows going in both directions so what is the "proper" direction?

Thanks
Ross


You should always rotate the engine the same direction it runs, i.e.: keeping the cam timing chains under tension. When you rotate the engine on the nut on the crankshaft under the right engine cover, it means clockwise. The cams will then rotate forward, towards the front of the engine.
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Re: Valve adjustment

Postby ajs350 » Thu Dec 30, 2010 3:26 pm

SanDogDewey wrote:Click Board index, under DIRECTORS, MEMBERSHIP QUESTIONS, CLUB NEWS & QUESTIONS go to ICOA CLUB NEWS. You'll see the link.


Got it. Thanks. It even has the cam chain adjustment description which was my next question!
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Re: Valve adjustment

Postby ajs350 » Thu Dec 30, 2010 3:28 pm

EMS wrote:
ajs350 wrote:
"Rotate the crankshaft one full turn in the proper direction". The picture on page 3-11 shows arrows going in both directions so what is the "proper" direction?

Thanks
Ross


You should always rotate the engine the same direction it runs, i.e.: keeping the cam timing chains under tension. When you rotate the engine on the nut on the crankshaft under the right engine cover, it means clockwise. The cams will then rotate forward, towards the front of the engine.


Makes sense EMS. Thanks.
Do you think I will need to purchase a new valve cover gasket or will the new one be Ok to use again?
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Re: Valve adjustment

Postby SteveG » Thu Dec 30, 2010 4:46 pm

ajs350 wrote:
Do you think I will need to purchase a new valve cover gasket or will the new one be Ok to use again?


My feelings are if the old one wasn't leaking and doesn't have any rips / tears / gouges about to go through, reuse it. Remember to use Honda Bond or similar in the appropriate spots, and DO NOT OVER TIGHTEN THE CAM COVER BOLTS.

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Re: Valve adjustment

Postby oilheadron » Thu Dec 30, 2010 5:33 pm

When I put my valve cover back on I tightened all of the cover bolts in stages until they just bottomed (like on early Goldwings for example). Is that the correct way??
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Re: Valve adjustment

Postby ajs350 » Thu Dec 30, 2010 5:57 pm

SteveG wrote:
ajs350 wrote:
Do you think I will need to purchase a new valve cover gasket or will the new one be Ok to use again?


My feelings are if the old one wasn't leaking and doesn't have any rips / tears / gouges about to go through, reuse it. Remember to use Honda Bond or similar in the appropriate spots, and DO NOT OVER TIGHTEN THE CAM COVER BOLTS.

Steve


Steve
When I looked up Hondabond I found 2 types; Hondabond 4 and hondabond HT. Which do you recomend?
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Re: Valve adjustment

Postby SteveG » Thu Dec 30, 2010 8:52 pm

Ross -

I like Hondabond HT (hi-temp). It works, works good, lets me take the cover off later without the gasket being "glued" on, and holds the gasket in place while manipulating it back into place while installing it. Other things work for other people, but I like this stuff :D

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Re: Valve adjustment

Postby SteveG » Thu Dec 30, 2010 8:56 pm

oilheadron wrote:When I put my valve cover back on I tightened all of the cover bolts in stages until they just bottomed (like on early Goldwings for example). Is that the correct way??


Sounds like it. The key here is not to over-tighten them. They are "shouldered" bolts, and tightening them more than snug will only pull threads out, not squeeze gaskets tighter.

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Re: Valve adjustment

Postby ajs350 » Thu Dec 30, 2010 9:48 pm

SteveG wrote:Ross -

I like Hondabond HT (hi-temp). It works, works good, lets me take the cover off later without the gasket being "glued" on, and holds the gasket in place while manipulating it back into place while installing it. Other things work for other people, but I like this stuff :D

Steve

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Thanks Steve. HT it is.
I have a good quality Mitutoyo verneer gauge that will measure to 0.01mm but the manual says to use a micrometer. Do you think my verneer gauge will be fine or should I invest in a micrometer?
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Re: Valve adjustment

Postby daves79x » Fri Dec 31, 2010 8:27 am

I assume you are using the one-piece tool for removing shims? I'm not familiar with it - I've always used the 2-piece tool that does not require you to rotate the crankshaft to remove shims. I think it's certainly faster to do the work. But both will work.

You do need to measure shims to within .01 mm. You'll see advertised shims in .05 mm (2.70, 2.75, 2.80 and so on), but you will find lots of them to be in between sizes and those can be used to fine-tune you adjustment to where you want it. Set your valves no tighter than .003 inch. I try to get mine at .004 or .005 inch.

You can reuse a good valve cover gasket for years. My 45,000 mile '79 is only on it's second one and the original one didn't really need replaced.

Dave
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