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Discussion Starter #1 (Edited)
Folks,

I'm going to document everything I'm doing here and post a lot of pics. I'll mark questions with a *** before and after the question so that anyone just looking to address issues and not read the rest can easily see when I have a question. I'll try to edit this Original post with answers as I get them so that people doing this in the future can have a point of reference when, like me, they don't know very much. Please chime in at any point, even if it is to say "Hey knucklehead...." and make a very direct point.

As discussed in earlier threads I've got a few spots that are leaking oil (really from the oil plug and one specific place where the cylinders and crank case meet). That's the reason for this work. I have to replace a gasket so I'll replace as many as possible for now.

I started today with starting to take my top end apart. I'm following the instructions verbatim from the Clymer Honda manual for twins, 1978-1987, 400-450cc.

At the point of discussion beginning here, the tank and seat are off, left side crank case cover is off, chain and front sprocket are off, battery disconnected and all electricals were moved under the seat by the PO and the upper brackets that bolt the motor to the frame are off. Bike status is the bike is in neutral, oil drained, oil filter out, and the bike is on the center stand.

I began this day by removing the carbs. 2 pics of importance; one showing that cam breather tube has been replaced with a small filter. I'm not sure where the other end originally connected, but this doesn't match the pic in my book. The second pic shows some grime around where the carb boots connected.

***(1) first question, the book references using a "solvent" several times for cleaning. Is there a recommended product that people love (and will be useful when I get to removing carbon build up)?***

breather tube


carb boot area on back of cylinder head. I put the bolts loosely back in so that I can keep up with them.


I then removed the valve cover. For anyone that has never done this, I lifted it and kind of rolled it forward and down just enough so that i could pull it out of the right side.

Here are a few pics of what was immediately underneath.
Left side:


Right side:


I was a space cadet and had not removed the exhaust, so I did that next. The bolts were actually not tightened down very well, so I'm wondering if there was actually a good seal. At any rate, pics of cylinder head exhaust outlets (again, nuts on the screws to keep up with them for now:
right side

left side


The pipes and the seal rings that fell out, coated in white stuff.


After getting this sorted, I moved on to removing the cylinder head bolts. I followed the ordering of the book. The bolts on the left rocker arm assembly, under the frame, were pretty tough to get out.

***(2) If you look in the picture below, there are plastic/rubber pieces on the bolts that are not on the other 6. What is this, why is it there, should I take it off, is this a concern? (ref: pic below, my bird finger is pointing at the 'thing' in question.)***

Super tight trying to get this out, and not shown/referenced in the book. Only on 2 bolts.



The cylinder head bolts on the right side do not have those pieces:


I then carefully removed the rocker arm assemblies. No idea if everything in there is looking good, since my virgin eyes are seeing this stuff for the first time.

Left:


Right:
***(3) In this pic, the front does not have same round piece that the rocker arm should guide down on to in this pic. It is pretty well stuck in the rocker arm assembly itself, but appears to be in fine shape. I can take a pic if needed, but I don't think this is a problem. Unless someone tells me otherwise I don't want to go pulling this out with novice force.***


And finally, where this thing is as of right now:


I am about to work on the bolts on the chain sprocket/cam connection and remove the cam so I can take the cylinder head off. Any guidance advice at making this a smooth process would be great.
***(4) can I turn this sprocket safely so that I can get to both bolts? Right now I only see one and I don't want to turn anything I shouldn't. This can be seen for reference if you go up 3 pics.***
***(5) The book references the need to tie the chain up to the frame with wire. When I go to actually lifting the cylinder head off am I going to need to have someone else with me to help get the chain through the cylinder head and not drop it down into the case or is there a smart way of doing this?***


My only worry so far (perhaps unjustifiably) is question 2. The rest seems like it might be routine new guy stuff. I know I'll have more questions as I work through this. Thanks in advance for any assistance!
 

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Don't take that rubber seal off the two head bolts that go into the left inner head bolts.
If you want some advice, use the Honda Service Manual instead of the Clymer's picture book.

PM sent for manual.
 

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Yes! You can spin that camshaft however you want to remove the bolts so you can remove the cam shaft gear and cam shaft.

It can be done solo. A helper is, well, helpful. I've removed the head on and off on my own. I used fishing line to tie up the chain. What I did was loop it around a few times the frame mount bolts (I removed the frame mount piece but put the bolts back in like you did on the head so I won't loose track of them).
I wrapped it around that, and then makes it pretty easy to tie up and untie.

Oh, yah, and my rocker arm assembly did the same thing! it pulled one of the round guides out with it. No big deal at all. Just leave and reassemble it as it is when you finish the service. (It also helps you remember what goes where as you got one round peg that goes into one open round hole.)

I just dismantled the whole top end down the crank last month on nearly the exact same model so it's quite fresh in my head. See this post if you like:
http://www.hondatwins.net/forums/62-engine-discussion/39987-pretty-massive-oil-leak-sudden-while-riding-hwy-cylinder-engine-trans-gasket.html
Post any Qs you have, feel free to PM me if you don't get a quick answer (the forum nav is a little hard for me to deal with, I'll at least see the PM alert!).

And by the way... you're not so terribly far away in Monterey. If you get into a real jam, PM, maybe I can ride down as an excuse to see Monterery again.
 

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Hi cato,

Welcome to the wonderful can of worms that is this engineered engine !l

At least your progress so far is going well, ie not broken stuff like a sheared off exhaust stud in the head, solid spark plug and sheared off head bolt....they all seem to feature on here......

Read up on similar threads on here, you will see and learn a lot......you have a manual of some description, Clymer and /or Honda etc.....you know of cmsnl for the excellent exploded views, a wonderful and free resource, print them off for your bike if you can.

Further similar thread reading will show why the left inner head bolts have a built on seal......and that you need a 10mm x 1.25 "tap" ( plug rather than taper or second cut , snap on do a really good one if expensive, still you get what you pay for ) to do a "good job". the head bolt hole threads must be absolutely clean all the way down to the bottom of the hole, as should all threaded holes really, cleanliness is next to godliness.

You have no doubt seen the "r" clipped clevis pin?? as well as the upper and lower "hexagons" on the rear of the cylinder block??

Figure out what they are for and if any need to be removed ????? as working it out for yourself ( via the manual and exploded views ) teaches you more than being "told"......but never be afraid to ask!!!

When the head ( well and truely stuck ????? ) and cylinder block ( well a truely stuck also ?? ) are removed, you will see the fragile pistons and their rings, so protect them from damage.

Do any valve springs look "odd" compared with the majority seen ? Any "yellow paint" on these valve springs ?

You seem to have some missing parts form this engine like the round "dowels" from the rocker arm carriers ?

You should be able to remove these by turning them and pulling them, clean and de burr if any, clean holes and refit, they should turn in their holes for snag free reassembly, that what I like them anyways....

read read and read, look, look and look, take your time and enjoy........pictures are great by the way, any chance of some better pictures of the valve springs ??

I tend to log stuff like compression pressures, breather "chuffing", cam sprocket timing mark "lean back ", cam chain "lift", balance chain shaft "dot" and "quadrant slot left" data, as well as mileage, oil filter cover floor debris, filter paper "trapped debris" and "oil dregs examination" ( metallic bits in the dregs of the drained old engine oil, as well as bits of black rubber, sealer etc. ), not to mention evidence of a prior strip down ( blue sealer, red sealer, stuff missing or fitted incorrectly ) before a strip down, as these are all good indications about engine condition and the carnage that may have taken place.
 

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At least your progress so far is going well, ie not broken stuff like a sheared off exhaust stud in the head, solid spark plug and sheared off head bolt....they all seem to feature on here...
Things like that can happen on ANY vehicle that's 35+ years old, especially if it spent a lot of its life out of doors (motorcycle engines don't have enclosed engine bays), if the last person to change a spark plug (if the plugs were ever changed) overtightened it, et cetera. Back around 1998, it took me all day to get a couple of injectors out of a 12-year old GM car because fuel had sat in the line around the o-rings for over a year. The other four injectors (and everything else that I had to remove) took less than two hours - go figure.

I haven't <KNOCKS ON WOOD> broken a spark plug off in an engine before, but I've seen people do it. Last time was a Toyota pickup. But in that particular case, I think the guy that did it might have gotten things a little cock-eyed, applying the force in the wrong direction.

Regards,
 

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Yes, it took me 10 seconds to remove a spark plug ( a normal time ) from an engine of one of these, took 3 hours for the other one with out shearing the plug off in the hole or trashing the plug thread, that's why you need more skill, experience and darn luck when working on older machines, consider really old machines like a tin lizzy where you cant get parts ( 3d printing these days, even 2 dissimilar metals, mega bucks!! ) .

So far this guy is doing ok, lets hope he keeps it that way.....but he has friends, forums, manuals, exploded views, instant camera's, even a paper pad and pencil !!

So take your time, if you don't know or are not sure, ASK!! A picture equals a thousand words and people can spot things.....

Read similar threads on here and other places, see, look, learn and benefit from others.....we want you to do a "good job" and ride your bike, a picture of your smile when done is all the payment required....but if we meet, then a beer would be fantastic:D
 

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Discussion Starter #8
Here's an update, y'all. After taking a little time to do what the Navy told me for a few days, I was able to get back into the garage and make another few steps. I removed the Cam sprocket, the cam shaft, got the cylinder head off, removed the cylinders, and while I don't have a pic, I got the pistons off. The first pics are everything as I worked my way down, the last two pics showing the cleaned up cylinder head and cylinders. I also loaded a video for good measure. I apologize that it's "horror movie" style. I would like to blame the flashlight on Navy habits of inspecting spaces on ships, but the truth is it was late, the flashlight was on my table, and the light switch was alllll the way on the other side of the garage... ;)

Lots of oil standing in there. I used rags to soak it up so I didn't dump it all the way down the front of the bike when I picked up it.


A word to folks using Clymers and the shop manual (as I now am), I didn't see anything specifically mentioning removing the engine hanger plate (but I may have missed it). If you're standing over your bike and pulling up and can't figure out why you can't remove your cylinder head, I recommend checking if this is still on. My angle didn't allow me to see it was still there 'til I was frustrated and stepped off from over the bike to see it.

Once I got the cylinder head off, I secured the cam chain with part of an old wire hanger. I wrapped it loosely around the chain and made an eye loop at the other end. I was able to hang it on the frame bolts where you mount the engine, and it isn't too hard to get throw the components as you remove them.


Those Pistons look like they've been linexed. Friends that have built few of these say it isn't too bad, but to me it looks horrible. Also, here's the underside of the valves:


Another shot of the pistons after the barrels were off:


I spent almost an hour and a half cleaning one valve, so I decided to call a local machine shop and have everything put in a wash and they glass bead blasted and rewashed everything. I'd love to have the time to put into doing it myself, but I just don't.

Here was the dreaded vid I mentioned before. Play it for your friends on Halloween:

Finally, I picked up the cylinder head and cylinders from the machine shop (no more paint on the cylinder heads!). I just dropped off my pistons and ordered new rings. I also dropped off my exhaust pipes to have a flat black ceramic coating put over all the oxidation on the chrome that will NOT come off.... I think it'll look great.





Making progress. I feel good about it. However, like I said before, if I'm jacking up something critical let me know!

Trav-
 

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I see a cylinder 'o'ring sitting atop the cylinders. Make sure you put a new set in when reassembling.
 

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After taking a little time to do what the Navy told me for a few days
My buddy said, "NAVY stands for Never Again Volunteer Yourself." And also to tell you to stay out of the reactor room unless you're doing something the officers would be calmer not knowing about. (He was on the Nimitz - back in the '80s, IIRC.) And he might have been the originator of the "box vacation" (if you REALLY don't want to do anything for a while, get a box, put a couple of things in it to rattle around when you shift it, and carry it around, displaying a "gee, I wish I didn't have to do this" look on your face whenever someone sees you - if you look more unhappy than their task would make you... they'll give it to someone who doesn't look as miserable (yet)).

I spent almost an hour and a half cleaning one valve, so I decided to call a local machine shop and have everything put in a wash and they glass bead blasted and rewashed everything.
They certainly look cleaner. Does bead blasting preserve the stellite coating on the valves? I've read that it's really, really thin (a couple of thousandths?).

Regards,
 

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Discussion Starter #11
My buddy said, "NAVY stands for Never Again Volunteer Yourself." And also to tell you to stay out of the reactor room unless you're doing something the officers would be calmer not knowing about. (He was on the Nimitz - back in the '80s, IIRC.) And he might have been the originator of the "box vacation" (if you REALLY don't want to do anything for a while, get a box, put a couple of things in it to rattle around when you shift it, and carry it around, displaying a "gee, I wish I didn't have to do this" look on your face whenever someone sees you - if you look more unhappy than their task would make you... they'll give it to someone who doesn't look as miserable (yet)).
I wish I had known that trick when I was enlisted. Now that I'm an officer the trick is to grab a blue folder (the ones you carry with documents that need signed) and walk around quickly between points. Everyone assumes you must be moving some really important document and not to bother you. Of course, it worked much better when I was an Ensign.


They certainly look cleaner. Does bead blasting preserve the stellite coating on the valves? I've read that it's really, really thin (a couple of thousandths?).
I have no idea about the coating at all. I certainly hope that is the case. I asked tons of questions before I dropped it off about maintaining the integrity of every component, and my local mechanic who was doing the work on this bike referred me to them since he uses them a lot. Truthfully however, I'd be guessing.

@dtsmjr8dan, yes you do! I have replacements. I just didn't remove it before I started snapping the photos. I just ordered new rings, so as soon as they get here I have everything in place to start putting it back together. I've probably made this harder than it should be by hitting you guys with pics/info of my progress, but I figured better safe than sorry.
 

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Isn't that stellite lining stuff hard as nails? Thin coating yes, but very very tough I've read I think.

Looks like you're on the right track with the rebuild. Re-assembly should be pretty easy for you I'd reckon. Very nice clean results from the shop.
 
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