Author Topic: Inspection window in front of the engine  (Read 1382 times)

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Offline _mark

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Inspection window in front of the engine
« on: June 29, 2021, 02:58:10 AM »
HI guys. Anyone has under his hands the 750 crankcase's naked (or open) halves ?
Reason is because i'm unsure if I placed or not the 18 mm oil gallery; after rebuilding the engine I found it in my remaining parts....
I can borrow a professional borescope but I need to know If I can access to the oil gallery thorugh the window in the front of the engine.
Hope someone that has a naked crankcase can contact me.
I need some close up pictures of the oil gallery seat and of the inspection window.
Thanks in advance.

« Last Edit: June 29, 2021, 03:05:50 AM by _mark »

Offline newday777

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Re: Inspection window in front of the engine
« Reply #1 on: June 29, 2021, 04:25:53 AM »
'Inspection window'????? Where did you get that term from for that?
Stu
Honda Parts manager in the mid 1970s Nashua Honda
My current rides
1975 K5 Planet Blue my summer ride, it was a friend's bike I worked with at the Honda shop in 76, lots of fun to be on it again
1976 K6 Anteres Red rebuilding project, was originally my brother's that I set up from the crate, it'll breath again soon!
Project 750s, 2 K4, 2 K6, 1 K8
2008 GL1800 my daily ride and cross country runner

Prior bikes....
1972 Suzuki GT380 I had charge of it for a year in 1973 while my friend was deployed and learned to love street riding....
New CB450 K7 after my friend returned...
New CB750 K5 Planet Blue, demise by ex cousin in law at 9,000 miles...
New CB750 K6 Anteres Red, to replace the totaled K5, I sold this K6 at 45k in 1983, I had heavily modified it, many great memories on it and have missed it greatly.....
1983 GL1100A, 1999 GL1500 SE, 1999 GL1500A

Offline _mark

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Re: Inspection window in front of the engine
« Reply #2 on: June 29, 2021, 04:27:50 AM »
'Inspection window'????? Where did you get that term from for that?
well ... what is the name and the pourpose of the hole in the first picture? thx

Offline 69cb750

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Re: Inspection window in front of the engine
« Reply #3 on: June 29, 2021, 04:48:39 AM »
The dowel and Oring is the oil feed between cases to galley and engine, important.
Cannot see it from plug.

Offline _mark

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Re: Inspection window in front of the engine
« Reply #4 on: June 29, 2021, 05:24:07 AM »
The dowel and Oring is the oil feed between cases to galley and engine, important.
Cannot see it from plug.
I know very well is important.
My original question is if someone has now the two halves splitted crankcase to check if I can reach the oil gallery with a professional borescope (6 mm head with straight and 90° camera)  that I can borrow . I need some close up pics. Thanks.
« Last Edit: June 29, 2021, 05:28:05 AM by _mark »

Offline 69cb750

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Re: Inspection window in front of the engine
« Reply #5 on: June 29, 2021, 06:21:51 AM »
Quote
My original question is if someone has now the two halves splitt crankcase to check if I can reach the oil gallery with a professional bore scope
I do, it won't work.

If you want a scientific test start the engine and watch oil spay out.

Offline _mark

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Re: Inspection window in front of the engine
« Reply #6 on: June 29, 2021, 06:29:58 AM »
Quote
My original question is if someone has now the two halves splitt crankcase to check if I can reach the oil gallery with a professional bore scope
I do, it won't work.

If you want a scientific test start the engine and watch oil spay out.
won't work what?  I'm not trying to start an engine without the oil gallery.
I need to check the possibility to reach the oil gallery with a borescope and check if such oil gallery ring is present or not. I don't remmeber if I placed or not and I don't want to re open again the halves for nothing.

Offline _mark

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Re: Inspection window in front of the engine
« Reply #7 on: June 29, 2021, 07:00:48 AM »
I finally got a pic from a guy.
I need to know if the channel that goes from the frontal window to the steel sleeve, is straight to be checked with a borescope. Thanks.

Offline flybackwards

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Re: Inspection window in front of the engine
« Reply #8 on: June 29, 2021, 07:27:15 AM »
That is an interesting question. I'm not sure that "window" is aligned with the centre bore of the filter - as far as I know its the machining access for the passage to the main gallery in the top case behind the cylinders. A suggestion is that you may be better off going in through the centre bore of the oil filter - there is one 90 degree turn and the knock pin should be right there. A straight scope with a 90 deg end fitting or a small (like dental) mirror and bright light may give enough visibility to see if the joint pin is in place. Otherwise chow down and open the cases while thinking about how you will upgrade your assembly process for next time!

Offline PeWe

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Re: Inspection window in front of the engine
« Reply #9 on: June 29, 2021, 08:51:40 AM »
Those plugs are for me "do not touch" plugs.
Probably hole needed when Honda machined the case and sealed with a plug or two.
Same with head inlet spigot, do not remove.

It is a good idea to not dissamble more than needed.

I bought a naked CB750 K2 case where everything was plundered except for those 2 plugs at front with a groove for a fat screw driver and rubber plug blocking oil channel at left close to gear mechanism.

Not much to see in there. Take engine apart and blow all oil channels after pump is removed with a pressure washer. Block or remove the rubber plug first.
CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
CB750 K2-75 Parts assembled to a stock K2

Updates of the CB750 K6 -1976
http://forums.sohc4.net/index.php/topic,180468.msg2092136.html#msg2092136
The billet block build thread
http://forums.sohc4.net/index.php/topic,49438.msg1863571.html#msg1863571
CB750 K2 -1975  build thread
http://forums.sohc4.net/index.php/topic,168243.msg1948381.html#msg1948381
K2 engine build thread. For a complete CB750 -75
http://forums.sohc4.net/index.php/topic,180088.msg2088008.html#msg2088008
Carb jetting, a long story Mikuni TMR32
http://forums.sohc4.net/index.php/topic,179479.msg2104967.html#msg2104967

Offline 69cb750

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Re: Inspection window in front of the engine
« Reply #10 on: June 29, 2021, 10:47:07 AM »
Quote
won't work?
Correct, you need to go in .500" inch, turn right for .500", turn right for 1", if you can do that post some photos.

Quote
I'm not trying to start an engine without the oil gallery.
99% of the oil will go through the tube, engine will be fine, 1% of the oil will leak or spray out the front (I am guessing), then it will be obvious.
« Last Edit: June 29, 2021, 10:48:52 AM by 69cb750 »

Offline _mark

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Re: Inspection window in front of the engine
« Reply #11 on: July 09, 2021, 04:00:11 AM »
HI guys. Finally I was able to find a professional borescope from GE/baker hughes.
The oil gallery is easy reachable but unfortunatley I forgot to put the sleeve and I put the o-ring only.
See the pictures.

Offline RAFster122s

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Re: Inspection window in front of the engine
« Reply #12 on: July 09, 2021, 07:09:54 AM »
That is a bummer!
How far do you need to tear it back down to access this to install the sleeve that is missing? Is the sleeve still available or is the original reusable?
Best of luck...
David
David- back in the desert SW!

Offline david 750f

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Re: Inspection window in front of the engine
« Reply #13 on: July 09, 2021, 08:33:34 AM »
That borescope is excellent!! I need to get one of those.
1976 CB 750F

Offline Don R

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Re: Inspection window in front of the engine
« Reply #14 on: July 09, 2021, 11:52:45 AM »
 Sorry to see the part is missing but thanks for the education on the problem and showing us the borescope. I admit to being a doubter about seeing in there. WoW.
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Offline PeWe

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Re: Inspection window in front of the engine
« Reply #15 on: July 11, 2021, 12:56:03 AM »
That borescope is excellent!! I need to get one of those.
You can get some project bikes or almost a new for what that borescope cost :)
Search GE XL Flex+

I'm sure Industrial inspections of expensive parts or safety inspections on aircrafts do not mind to pay $20.000US and more for a good borescope.

I have a chinese wifi endoscope to my phone for max 20 bucks! ;D

CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
CB750 K2-75 Parts assembled to a stock K2

Updates of the CB750 K6 -1976
http://forums.sohc4.net/index.php/topic,180468.msg2092136.html#msg2092136
The billet block build thread
http://forums.sohc4.net/index.php/topic,49438.msg1863571.html#msg1863571
CB750 K2 -1975  build thread
http://forums.sohc4.net/index.php/topic,168243.msg1948381.html#msg1948381
K2 engine build thread. For a complete CB750 -75
http://forums.sohc4.net/index.php/topic,180088.msg2088008.html#msg2088008
Carb jetting, a long story Mikuni TMR32
http://forums.sohc4.net/index.php/topic,179479.msg2104967.html#msg2104967