Author Topic: New to building. Like really new. Like moron new.  (Read 7692 times)

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Offline MoMo

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Re: New to building. Like really new. Like moron new.
« Reply #25 on: June 30, 2013, 12:36:46 PM »
Yes. You most likely will need the head off to remove the broken plug as it will have to be drilled and removed with an easyout.  Not encouraging is it?...Larry

Offline Stev-o

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Re: New to building. Like really new. Like moron new.
« Reply #26 on: June 30, 2013, 01:02:52 PM »
Oh #$%*e!   +1 easy out.
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline Jeff750

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Re: New to building. Like really new. Like moron new.
« Reply #27 on: July 01, 2013, 09:37:43 AM »
Is there any threads on removing cam/rocker? Little intimidated at this point
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Offline Bankerdanny

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Re: New to building. Like really new. Like moron new.
« Reply #28 on: July 01, 2013, 01:29:56 PM »
The rockers are attached to the valve cover. Once you remove the cam chain the cam should just lift out.
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Offline mrrch

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Re: New to building. Like really new. Like moron new.
« Reply #29 on: July 02, 2013, 02:26:22 PM »
The threaded portion is still in the head and it does already have a hole thru it so you MIGHT get lucky with an easy out. But I do think there will be some head removal upcoming. I had one break off like that on a spare head and the machine shop still had a tough time getting it out.
my build

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Offline Jeff750

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Re: New to building. Like really new. Like moron new.
« Reply #30 on: July 02, 2013, 04:17:18 PM »
Ya. I've decided to take the top end apart to figure out why it's not turning all the way over.

We shall see
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Offline Jeff750

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Re: New to building. Like really new. Like moron new.
« Reply #31 on: July 13, 2013, 03:55:14 PM »
Damn near killed myself and my back trying to get it apart but I did and this was my reward. I believe we have a problem.
But the good news is that the crank will turn freely now.
Time to regroup with a beer and figure out the next move tomorrow.
With enough ignorance and enthusiasm I can do anything!

Offline edhaeuser

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Re: New to building. Like really new. Like moron new.
« Reply #32 on: July 13, 2013, 04:23:29 PM »
Looks like a lot of crud on that #2 piston.  How does the cylinder look?  Looks like it may be a good thing that you took it apart.

Offline Jeff750

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Re: New to building. Like really new. Like moron new.
« Reply #33 on: July 13, 2013, 04:39:24 PM »
Full of crud. Tried to up load a pic but file was too big.

So what's the word? Can one simply clean up something that looks like this with scotch bright? Or am I buying one or four new piston heads?
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Offline edhaeuser

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Re: New to building. Like really new. Like moron new.
« Reply #34 on: July 13, 2013, 04:49:03 PM »
Full of crud. Tried to up load a pic but file was too big.

So what's the word? Can one simply clean up something that looks like this with scotch bright? Or am I buying one or four new piston heads?

I'm no expert, but I think a lot will depend upon how the cyclinders look.  If they need to be rebored, (because of pitting or scoring) then new pistons are probably needed to match the new bore size.  If you can just get by with a cylinder honing, then new rings and you should be good to go.  I would think that the pistons could be cleaned up.  I use a soda blaster...I don't recommend bead blasting though.  They can also be carefully scraped clean.  I would think that scotchbright would be OK.  I will leave other more experienced builders guide you on that.

Offline Jeff750

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Re: New to building. Like really new. Like moron new.
« Reply #35 on: July 14, 2013, 08:40:33 AM »
FUBAR?
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Offline edhaeuser

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Re: New to building. Like really new. Like moron new.
« Reply #36 on: July 14, 2013, 09:44:18 AM »
FUBAR?

The head will probably be repairable.  The valves may be shot though.  I would bead blast the combustion chamber to clean it up, and have the seats recut.  If you have no experience, a reputable engine shop can do this for you.  They can get that broken spark plug out too.  They will check the valves, valve guides, and cyclinders and let you know what needs to be done.

Offline 70CB750

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Re: New to building. Like really new. Like moron new.
« Reply #37 on: July 14, 2013, 10:08:07 AM »
What Ed says, disassemble it, have the chamber blasted - I paid $35 to get mine done - and examine and measure what you got.  It may still be usable.
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Offline Stev-o

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Re: New to building. Like really new. Like moron new.
« Reply #38 on: July 14, 2013, 10:33:10 AM »
It may be repairable but not worth it if you can find a good replacement at a fair price.
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Offline iron_worker

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Re: New to building. Like really new. Like moron new.
« Reply #39 on: July 14, 2013, 10:47:17 AM »
Like was said, it might be easier to find a serviceable head used. Although its hard to say how much work that head may need also.

IW

Offline edhaeuser

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Re: New to building. Like really new. Like moron new.
« Reply #40 on: July 14, 2013, 11:24:37 AM »
Like was said, it might be easier to find a serviceable head used. Although its hard to say how much work that head may need also.

IW

Yeah,  I am so bent on using what I have that I forget that sometimes is easier and cheaper to find a replacement ;-)

Offline Stev-o

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Re: New to building. Like really new. Like moron new.
« Reply #41 on: July 14, 2013, 11:28:48 AM »
Like was said, it might be easier to find a serviceable head used. Although its hard to say how much work that head may need also.

IW

Yeah,  I am so bent on using what I have that I forget that sometimes is easier and cheaper to find a replacement ;-)

I'm just the opposite since I have quite a large spare parts collection.
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline Jeff750

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Re: New to building. Like really new. Like moron new.
« Reply #42 on: September 13, 2013, 06:36:51 AM »
Question on hones.
There's still a bit of rust and garbage in my jugs. Called a local garage and they said about $50 per hole.

Is this something i can do myself? with say this tool?
http://www.princessauto.com/pal/en/Engine-And-Transmission/4-in-Engine-Cylinder-Hone/8243537.p

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Offline 70CB750

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Re: New to building. Like really new. Like moron new.
« Reply #43 on: September 13, 2013, 06:47:20 AM »
Not that one, it is easy to take too much with it.  You want flex hone:

http://www.brushresearch.com/brushes.php?c1=1

There is also thread here where somebody used sand paper to cross hatch his cylinders.  Myself, I found flexhone on ebay for good price/shipping when I had to make sure new rings will set in correctly.

Flex hone with cordless drill at low and plenty of oil and you will make nice pattern in the cylinder.

Check out pictures on my page, post #58:

http://forums.sohc4.net/index.php?topic=115305.50
« Last Edit: September 13, 2013, 06:49:46 AM by 70CB750 »
Prokop
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Offline Jeff750

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Re: New to building. Like really new. Like moron new.
« Reply #44 on: September 13, 2013, 06:50:51 AM »
Very cool thank you. Really appreciate all the advice I can get off of you guys
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Offline Jeff750

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Re: New to building. Like really new. Like moron new.
« Reply #45 on: September 13, 2013, 07:27:43 AM »
Do you remember what diameter flex hone you bought? Thanks
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Offline 70CB750

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Re: New to building. Like really new. Like moron new.
« Reply #46 on: September 13, 2013, 08:03:50 AM »
Do you remember what diameter flex hone you bought? Thanks

I am pretty sure it was 2 1/2"  but I can check tonight.
Prokop
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Offline 70CB750

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Re: New to building. Like really new. Like moron new.
« Reply #47 on: September 13, 2013, 05:11:39 PM »
Yes, I was right, 2.5"  flex hone, 320 grit.
Prokop
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Offline HondaMan

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Re: New to building. Like really new. Like moron new.
« Reply #48 on: September 13, 2013, 08:58:41 PM »
FUBAR?

Wow, that's about as bad a head as I've seen! I have a K0 head that started out like that, ended up having big holes eaten into the chamber from the water damage. It's scrap now, use it for various 'experiments'.
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Offline jojo

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Re: New to building. Like really new. Like moron new.
« Reply #49 on: September 13, 2013, 09:11:46 PM »
$300!

Wow, a steal! You can get a whole new wiring harness from PartsNmore.com in Canada for $75, or from CB750Supply for about that, American.

If my wiring is very old and crusty and im going to need to rewire anyways is a new harness the way to go?