The International CBX Owners Association

Kool_Biker wrote: .....so I will hone my valve lapping skills
Aris

Man do I love a good pun!

Thank you Aris for posting all of your pain and (soon to be) glory. Your attention to detail and meticulous thought process is inspiring.

Steve

PS - May my 82 last 100,000 miles before a teardown. (Here is where the nonexistent fingers crossed emoticon is placed)

Steve

What a splendid idea , we can all do with a 'fingers crossed' emoticon.

Come on Nils, surely there must be a way to add one, we will all be grateful for this with me leading the way

Aris

MODERATOR EDIT! Aris, I am keeping for you.

All
Cam assessment day today ... The way I see it ...
1. Exhaust cams, PASS
2. Inlet-R cam on the limit but still (sort of) PASS
3. Inlet-L cam on the limit for most lobes (green underlines), with one slightly below the limit (red underline), so FAIL
But I would hugely value your inputs. Do I (really) need to discard the Inlet-L cam?
Cheers, Aris

Is that the dreaded #1 again? ;)

I wouldn't replace it - You have several 37.20's there and the difference between those and the one 37.17 is infinitesimally small

I'd put it together and try my best to wear it out . . . . but you'll never get there

Don

Aris:
Most used cams that I've actually measured seem to run near the lower limit. If the lobe otherwise looks good, I'd use it and not worry.

Dave

Don, Dave

Fantastic news from both of you guys; I had a look at the price for an NOS cam, and its not a joke.
The lobes seem perfect so now I will proceed to platigauge all cam journals (again, after having completed a bit of very fine journal polishing).

Assuming these pass as well, the cams stay

P.S. I see Nils got my input for a 'fingers crossed' emoticon pretty seriously

Thanks everybody for your speedy and encouraging replies.

Aris

MODERATOR EDIT! Aris, I am keeping for you.



Thanks for this most important emoticon!!!
Aris

Kool_Biker wrote:MODERATOR EDIT! Aris, I am keeping for you.



Thanks for this most important emoticon!!!
Aris

Aris,

Personally, I imagine you wanted to right after you were by the sight of the inside of your motor. I would be a little to tear that far into it, so many parts to get . We are all for you, and as soon as you are again, we will all


Best,

N.

SteveG wrote:
Thank you Aris for posting all of your pain and (soon to be) glory. Your attention to detail and meticulous thought process is inspiring.

Best thread by far. It's a keeper. I'm sure this will become a reference for the future, especially with all of the well detailed photos.
Don't keep us waiting too long, Aris. I was starting to get withdrawals when you hadn't posted in a few days....

Barry

With my new found confidence re the state of the cam lobes and everyone's support, it is time to assess the head cam journal tolerances. In preparation, the cam journals were lightly polished by hand (this is otherwise known as 'elbow grease') Then the cam cap mating surfaces were lightly 'cleaned' with wet & dry 1200 paper Everything was meticulously cleaned (brake cleaner spray for ever ) , the left - exhaust cam was put on the head, Platigauge was applied and then the caps were put on, torqued down with their cam bolts, lightly oiled and to the recommended torque.
Good news . Everything seemed to be well inside Honda tolerances! When the above process was repeated for the left exhaust cam, the results were equally promising! A good day overall!

Next I will proceed to do same for my two inlet cams. Assuming things continue going well , a big part of my head 'refurbishment / measurements' work will have been over. Then I can focus on the other side of the head - VALVES!

Aris

Well, the inlet cams have not let me down, as lately, I seem to be getting a bit of luck I could do with . All clearances were well within limits.
Over and above, all 4 cams seemed to rotate freely when, liberally lubricated, they were put on the head with their caps, and correctly torqued down. Very satisfying to apply and observe!

The only thing left, I guess, is check the cams for runout, as recommended in the shop manual. Although I know I will not have a problem in this area, I will perform this easy test in any way. Only issue, I do not yet have the equipment to do at home, so will perform when I visit my friend Dimitris machine shop in the next few days.

Notwithstanding the above runout test, this is the end - a happy end - of the cams side of the head .

Next I will focus on its other side, where the valves and all of their paraphernalia reside. Wish me luck.

Best, Aris

Nice to see you getting some good luck Aris. Lets hope it lasts
As others have said, this thread is definately a keeper, because of the incredibly detailed photos.

Cheers
Chris J.

Still with the cylinder head today, BUT opening a new chapter at last: VALVES.

This chapter begins with a good clean, to remove what ever debris was created during the cams operations and any remaining glass (paranoid ). The head was dried with lots of compressed air and next the cylinder head domes and valve seats were cleaned from carbon buildup, ever so lightly, using the softest 3M abrasive on the Dremel. Then all 24 valves were cleaned using my Bosh drill at high speed and a rotary brass brush. They were subsequently carefully inspected for any sort of visible damage.
Happy to report, other than the small cracks in exhaust valves in cylinder no 1 (reported extensively earlier on), there was none . I then went on to lap one (inlet) valve to create a gas-tight seal between the valve and the head, using fine grinding paste and a small hand lapping stick.
All very easy, satisfying and looks great.
BUT, I have stopped here to ensure I do not get overenthusiastic with anything. In fact, I have a question for you chaps; below is a pic of an inlet valve BEFORE cleaning.
There's clearly a little bit of carbon buildup (red surround), exactly where the valve/seat seal should be.
How can this be explained, considering that the seats and valves were professionally cut (and I guess lapped) only 110 miles ago? I would like to understand this before I get on with lapping all remaining valves. Any suggestions extremely welcome. I am also happy to be told I am splitting hair Cheers, Aris

Aris:
I think the dirty little secret is that most pro shops just cut/reface the seats and install new valves. They do not hand-lap each valve. I've been told to just run them and they'll seat themselves. I hand lap them anyway. It's actually kind of fun once you get the hang of it. I'd continue doing what you are doing for peace of mind. You seem to be getting a nice wide sealing surface.

I just buttoned up the lower end of the engine that had the cracked crankcase. Everything is finally ready to bolt back on. Installed the pistons with the intention of getting the cylinder on, but found out I didn't have a base gasket. Oh well, worked on a set of carbs the rest of the day.

Carry on - looks like you are well on your way.

Dave

Don wrote:

Kool_Biker wrote:I am still puzzled at how I could have missed something so gross. After all, its not rocket science; all galleys are logically sculpted and to date, I have not managed to find any little 'crypts' where the glass residue was hidden, waiting ...
But of course, we all know, it did, and it was ....

Dave is probably every bit as sanitary and meticulous when rebuilding these things as you are Aris and he warned me about possibly finding 'junk' in the oil screen after he put my engine together - He's seen it many times and has redoubled his efforts to make sure everything is sparkling clean before buttoning them up, but you still find trash afterwards. He strongly advised me to drop the pan and clean out the screen everytime I changed the oil until it eventually turns up clean. There was a good bit of residue in the screen the first oil change and maybe a little less than half as much the second time and relatively none the third time I removed it

It does make you scratch your head and wonder . . . .

Don

What sort of debis did you find in the screen ? Since these screens are quite coarse.....this suprises me.

Did you take pics ?

Thanks........ Mike