new guys 79 woes


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scotty
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new guys 79 woes

Post by scotty »

Hi guys, hope you can help, i have a 79 abandonded project, the head was off and i could see 6 new pistons and crosshatching in the cyl, the head had all new valves and seals and i adjusted the valves on the bench, but when i went to set the engine to TDC it wouldnt turn, i ended up with a steel plate on top off the studs and outer bolts being tightened down to draw the cylinders up, the bottom ring of all 6 oil rings had been wedged down between the cylinders and the pistons, i replaced the rings and bored another set of cylinders the assembled the engine, upon starting it it sounds like a bag of hammers in there, i only ran it for a minute or two, it wont idle, i saw reference on the net about the cam positioning and wrong info in the manual, when i pulled the valve cover at TDC ALL the cam lobes on cyl 1 and 6 point in toward the plugs, i believe this is wrong? if so
1. what is the best way to rectify this, the left cams are easier to move are they not? should i rotate 360o and then move the left cams?
2. i found a piece of semi round metal in the pan that looks like a piece of the inner cage from a bearing, can the lower case be removed without dismantling the whole engine
3, thanks so much

daves79x
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Re: new guys 79 woes

Post by daves79x »

First of all - welcome! A couple pieces of advice - use some punctuation so we can decipher what you are asking - then get a proper shop manual. Yes, your cams are wrong and need installed EXACTLY as the proper shop manual shows. You'll need to remove them all and start over. Lots of things can be causing your noise - everything from plugged carbs to clutch rattle to a rod about to grenade to something else amiss deep in the engine. Since it was apart that far, who knows what else is screwed up. I'd personally split the cases and investigate everything in the bottom end. That's the only way you'll know what's what and otherwise you'll be chasing noises forever. These are not the quietest engines around when totally right, so an experienced ear might be needed to differentiate between a normal noise and something else.

The cams for sure need corrected and the carbs need completely gone through first, before you try running it again. After that, ask away!

Dave

PS to all: There can't possibly be that many incorrect shop manuals out there showing incorrect cam installation. Only the very earliest ones did. Where do all these engines turn up with cams installed wrong? Somebody just guessing? Awfully expensive guesswork.

EMS
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Re: new guys 79 woes

Post by EMS »

daves79x wrote:
PS to all: There can't possibly be that many incorrect shop manuals out there showing incorrect cam installation. Only the very earliest ones did. Where do all these engines turn up with cams installed wrong? Somebody just guessing? Awfully expensive guesswork.
There are a lot of 4-cylinder experts who are not shy applying their experience to a CBX motor. It always amuses me, when I surf other motorcycle forums, how many people are out there, who feel they are competent to talk CBX.
I am not saying it is rocket science and you need to devote your life to the CBX in order to be proficient with it, it's just a little different than the other Hondas and you need to know about it. :think:

Rick Pope
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Re: new guys 79 woes

Post by Rick Pope »

My shop manual was ordered through my local dealer in early 1992, and it has the in-correct cam installation shown. Old stock? Not dealer stock, as I had to wait for it.
Rick Pope
Either garage is too small or we have too many bikes. Or Momma's car needs to go outside.

scotty
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Re: new guys 79 woes

Post by scotty »

good news is today i figured it out and swapped the left cams now runs great.
thought i did ok by numbering my questions, no answers to #2 yet though

EMS
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Re: new guys 79 woes

Post by EMS »

When you turn the engine upside down, the lower case can be removed with all internals remaining. Haven't split cases in a while, but I seem to remember that's how it is.

daves79x
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Re: new guys 79 woes

Post by daves79x »

A photo of the foreign metal piece would be helpful. Something could have been dropped while the engine was apart before, but you'll want to know for sure. Yes, just turn the engine upside down and the lower case half can be removed. Of course, the starter, alternator, clutch assembly need to come off. I'd strongly advise a shop manual to do this. I've done it dozens of times and still like to have the manual right there.

Glad it sounds better, but just swapping the cams should not have quieted the engine down. They run and sound pretty normal (for a brief time) with the cams 180 out. But anyway, glad it sounds better to you.

Dave

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