Author Topic: Taking apart engines - order of operations - cb750  (Read 1495 times)

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Offline SKTP

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Taking apart engines - order of operations - cb750
« on: April 26, 2010, 12:14:25 pm »
So what order do you all disassemble your engine? Or is there a wrong way?
1978k rebuild thread http://forums.sohc4.net/index.php?topic=68423.0
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2004 Honda CR-V
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Offline Hannibal Smith

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Re: Taking apart engines - order of operations - cb750
« Reply #1 on: April 26, 2010, 02:22:19 pm »
I wish I had been warned profusely, so I will start the favor!

DO NOT SMACK YOUR CYLINDER HEAD WITH ANYTHING!

No rubber mallets, no wood, NOTHING!!!!!!!!!!!!!!!!!!!!!!!!!

There are 2 little recesses left/right between the cylinder head and the head (part with the valves) get a small prybar or wood wedge etc. and pry these two asssemblies apart. If you even kiss the fins with a rubber mallet you will break fins.

I just busted open my first Honda SOHC motor, and broke 2 fins and had to have them welded. I just love tapped it with a soft rubber mallet, and pieces went flying.

Those fins are brittle and thin. I am used to water-cooled mills, and didn't realize just how sensitive those fins are.
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Offline cookindaddy

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Re: Taking apart engines - order of operations - cb750
« Reply #2 on: April 26, 2010, 02:38:52 pm »
Get yourself the factory manual for the 78K (it's here in the Manuals thread) and read that. Honda gives you a pretty good step by step (and reassembly).
George with a black 78 CB750K (in Lion's Head, Ontario, Canada)

Offline SKTP

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Re: Taking apart engines - order of operations - cb750
« Reply #3 on: April 26, 2010, 03:13:59 pm »
Oh yes, I've got manuals...at least 4 now...I'm trying to score some tips from people who have actually done it before I take the plunge. Like Hannibal's seems like a good one. I love it when a plan comes together...
1978k rebuild thread http://forums.sohc4.net/index.php?topic=68423.0
BIKE OF THE MONTH - OCTOBER 2017
2003 Ducati M800ie
1997 Honda CR-V
2004 Honda CR-V
1966 Honda S90

Offline cookindaddy

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Re: Taking apart engines - order of operations - cb750
« Reply #4 on: April 26, 2010, 04:51:33 pm »
Sorry I misunderstood, you had asked about order of operations, not about tips. There are lots and lots of tips here.

I looked at your rebuild thread. I am just finishing doing mine, of the same bike. It was a great project for me and I hope that yours will be also.

Tips:

Lots of baggies and clear labels for where the parts came from.

I checked the length of the bolts as they came out of the holes, just to make sure, and made pictures in my notepad. Turns out that the PO hadn't put the right bolts in the right holes in all cases but I figured that out when I came to put the thing back together by checking how much free length there was before threading them home.

Look at the posts about modifying a Harbour Freight engine support to hold both ends of the motor both top and bottom. I didn't do this, but I wish that I had.

I am sure that you will get lots of other tips here.

Good luck


« Last Edit: April 26, 2010, 04:56:01 pm by cookindaddy »
George with a black 78 CB750K (in Lion's Head, Ontario, Canada)

Offline SKTP

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Re: Taking apart engines - order of operations - cb750
« Reply #5 on: April 26, 2010, 05:41:03 pm »
thanks...cookindaddy

I search your profile and you have many threads...

I'll be going over this engine removal tips thread for sure:
http://forums.sohc4.net/index.php?topic=39702.msg409010#msg409010

is there a main build thread somewhere also? I'll search some more later...but if you know where it is off-hand, it'd be greatly appreciated.

In other random news, I lived in Toronto for 32 years, but I am now in Orange County California.
1978k rebuild thread http://forums.sohc4.net/index.php?topic=68423.0
BIKE OF THE MONTH - OCTOBER 2017
2003 Ducati M800ie
1997 Honda CR-V
2004 Honda CR-V
1966 Honda S90

Offline Hannibal Smith

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Re: Taking apart engines - order of operations - cb750
« Reply #6 on: April 26, 2010, 06:02:06 pm »
Putting motors back together, there are a lot of good tips in that department.

You can see the green paint on the shift drum fastener- I mark every internal fastener after they get torqued when I assemble, don't want to miss that kind of stuff!

When you put your cases back together, do a "dry build" with all the fasteners so that you have every stinkin' one laid out-

Make sure that you have the 2 flanged crank gaskets on the crank before you put the cases back together, in fact, have every gasket and seal accounted for and there when you re-assemble

Follow my build "P38 Racer" in Project section