Author Topic: Not sure what this is do I remove it?  (Read 256 times)

Offline Macabethiele (Ted)

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Not sure what this is do I remove it?
« on: March 29, 2021, 11:10:18 PM »
Whilst cleaning my lower crankcase yesterday I noticed this bolt/cap/plug not sure what it is as I see no reference to it in my manual.

The photo is upside down it is underneath where the points cover sits. Should I remove it ?


.what is this cap-bolt by Macabe Thiele, on Flickr
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Offline philward

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Re: Not sure what this is do I remove it?
« Reply #1 on: March 29, 2021, 11:22:07 PM »
Not a 400 expert but on 500/750, its the oil gallery plug - oil travels along this to mains/big ends/etc. I always remove to clean oil ways properly - you can blow through to each main bearing oil feed for example
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Offline Bryanj

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Re: Not sure what this is do I remove it?
« Reply #2 on: March 30, 2021, 12:51:27 AM »
On the other end is a little push in plug held in by the alternator cover and if you leave the cover of whilst starting the engine it will dissapear into a dim and distant corner plus large black puddle under bike

Offline Oddjob

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Re: Not sure what this is do I remove it?
« Reply #3 on: March 30, 2021, 04:15:52 AM »
Make sure you use a decent spanner/socket when removing it as they tend to round off easily.
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Offline Trigger

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Re: Not sure what this is do I remove it?
« Reply #4 on: March 30, 2021, 07:53:56 AM »
Heat it up with a blow torch until you can smell the rubber getting hot and as has already been said, use a good socket or clamp it in a vice and turn the case to get it moving  ;)

Once off, you can use a long bar to push the plug out the opposite end. A good clean out and replace the O' rings.

Offline Macabethiele (Ted)

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Re: Not sure what this is do I remove it?
« Reply #5 on: March 30, 2021, 09:31:03 AM »
Make sure you use a decent spanner/socket when removing it as they tend to round off easily.
Although the nut looks unmarked a 14mm socket seems  a poor fit as the head looks almost as though its an angled top, 9/16 AF no better. I used my impact driver - straight off no issues. The other end is solid so I will put a bar through & tap it out.
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Online Rozabikes Tim

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Re: Not sure what this is do I remove it?
« Reply #6 on: March 30, 2021, 10:53:26 AM »
On the other end is a little push in plug held in by the alternator cover and if you leave the cover of whilst starting the engine it will dissapear into a dim and distant corner plus large black puddle under bike
Embarrassed to say I actually did that many years ago. Hard way to learn!!
One day I'll have the time to restore it, not just talk and dream....

Offline mike the bike

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Re: Not sure what this is do I remove it?
« Reply #7 on: March 30, 2021, 11:01:18 AM »
Don't remove it if you don't have to.
Where's that 10mm socket got to?

Offline SumpMagnet

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Re: Not sure what this is do I remove it?
« Reply #8 on: March 30, 2021, 12:08:58 PM »
I am considering whether or not to remove the one on my 750 while I have the cases apart, but am really concerned about chewing it up....as it's probably never been undone in the bikes 40+ year life. I can see the benefit of flushing out anything that would accumulate sludge and muck, but...can also see a nightmare of chewed ally and a plug that still didn't come out after I toasted the o-rings
Are they obtainable? I had a quick look and couldn;t see anyone selling them.
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Offline Nurse Julie

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Re: Not sure what this is do I remove it?
« Reply #9 on: March 30, 2021, 02:51:59 PM »
I am considering whether or not to remove the one on my 750 while I have the cases apart, but am really concerned about chewing it up....as it's probably never been undone in the bikes 40+ year life. I can see the benefit of flushing out anything that would accumulate sludge and muck, but...can also see a nightmare of chewed ally and a plug that still didn't come out after I toasted the o-rings
Are they obtainable? I had a quick look and couldn;t see anyone selling them.
Clean the oil gallery, it's where most of the shite collects. I have the bungs in stock.
Im a Nurse, trust me, this won't hurt.....much !!!

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Offline philward

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Re: Not sure what this is do I remove it?
« Reply #10 on: March 30, 2021, 03:14:18 PM »
I am considering whether or not to remove the one on my 750 while I have the cases apart, but am really concerned about chewing it up....as it's probably never been undone in the bikes 40+ year life. I can see the benefit of flushing out anything that would accumulate sludge and muck, but...can also see a nightmare of chewed ally and a plug that still didn't come out after I toasted the o-rings
Are they obtainable? I had a quick look and couldn;t see anyone selling them.

I've had no trouble removing with 6 point socket
Current Bikes:-
Honda CB750K2 (1975)
Honda CB500K2 (1973)
Honda CR750 Replica (1972)
Kawasaki ZZR1100D3 (1995)
Kawasaki ZZR250 (1990) Project (Not started)

Offline SumpMagnet

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Re: Not sure what this is do I remove it?
« Reply #11 on: March 30, 2021, 05:57:15 PM »
Thanks @Nurse Julie   .... feel a bit happier trying to take out something when I know I can replace it.
CB750F2 - in pieces
CB900F Hornet - the daily transport

 

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