Honda-SOHC

SOHC.co.uk Forums => CB350/400 => Topic started by: Drew400 on October 12, 2014, 06:04:15 PM

Title: Should that hole be there?
Post by: Drew400 on October 12, 2014, 06:04:15 PM: Hello experts,

I'm feeling rather pleased with myself for completing the bottom-end rebuild up to fitting the clutch. However, there's a hole in that there crankcase that I'm wondering if it should have been plugged before I got this far.

The attached photo shows a properly cast feature, but I can't see reference to it in my diagrams/manuals (unless it's some kind of inspection/access hole that I'll get to later in the build). If, in the meantime you can shed light or, better still, put my mind at rest, that would be much appreciated.

Cheers all,

D.
Title: Re: Should that hole be there?
Post by: Trigger on October 12, 2014, 06:35:53 PM: Sorry Drew, can't really see with the clutch in the way. Is the hole smooth inside?
Title: Re: Should that hole be there?
Post by: Drew400 on October 12, 2014, 07:05:39 PM: The 'hole' is a perfect circlular aperture in the crankcase wall behind the clutch. If I poke a screwdriver through, I can see it from the vacant cylinder base(s).

Does that help?

Ta, D.
Title: Re: Should that hole be there?
Post by: Trigger on October 12, 2014, 08:46:23 PM: Drew. Pop the clutch off and take another picture. I would not like to comment on something i can not see.
Title: Re: Should that hole be there?
Post by: Drew400 on October 12, 2014, 10:22:20 PM: Job for next weekend, then.

Cheers, D.
Title: Re: Should that hole be there?
Post by: Drew400 on October 16, 2014, 05:31:24 PM: Hi Trigger,

Does this image help...?

Cheers,

D.
Title: Re: Should that hole be there?
Post by: Trigger on October 16, 2014, 06:11:24 PM: If it is smooth inside it will just be a molding hole. Still can not see it very well. Found a picture of a crank case but, the hole is just out of sight>>> http://www.dotheton.com/forum/index.php?topic=43751.0 And i do not have any old crank cases to compare.
Title: Re: Should that hole be there?
Post by: Drew400 on October 16, 2014, 06:16:27 PM: Thank you Trigger.

Anyone else got a crank case to hand that can help me with this one?

It would be a shame to put mine all back together and find I'd missed a vital component, eh?!

Cheers,

D.
Title: Re: Should that hole be there?
Post by: Bitsa (Ralph Wright - RIP) on October 16, 2014, 07:08:45 PM: Agree with trig looks to neat so must be there from production
Cheers
Bitsa
Title: Re: Should that hole be there?
Post by: Drew400 on October 16, 2014, 07:21:41 PM: I agree with that assumption. My fear is that it should be plugged with a bung/grommet or (worse) some engineering part that I've forgotten to reinstall!
Title: Re: Should that hole be there?
Post by: Bitsa (Ralph Wright - RIP) on October 16, 2014, 07:24:16 PM: Drew
I have a Honda cd parts list for the 400 somewhere will dig it out and have a look for you but have to say the last one I rebuilt dont recall that
Cheers
Bitsa
Title: Re: Should that hole be there?
Post by: Trigger on October 16, 2014, 07:26:48 PM: It will Not be a bung and from your non-close up shot, all parts seem to be in place.
Title: Re: Should that hole be there?
Post by: Bitsa (Ralph Wright - RIP) on October 16, 2014, 07:42:23 PM: Agreed but will confirm with the CD
CHEERS
BITSA
Title: Re: Should that hole be there?
Post by: Drew400 on October 16, 2014, 08:10:55 PM: Thanks again chaps.

I guess it could simply relieve crank case oil pressure/allow air flow. I can't see how, if the bike were to be laid on its side, oil wouldn't flood the clutch housing. However, I've never ridden any bike that hard and like to pick them up quickly if they find themselves on their sides!

There's another 'hole' in the crankcase wall (this time an oblong one) below the gear selector shaft. It's clearly visible in the second photo below. I guess this would allow any excess oil from my above assumption to drain back into the sump.

Cheers,

D.
Title: Re: Should that hole be there?
Post by: Trigger on October 16, 2014, 08:14:02 PM: Yep, second pic is a oil way.
Title: Re: Should that hole be there?
Post by: Drew400 on October 16, 2014, 08:15:54 PM: I'm starting to relax already!

ta, D.
Title: Re: Should that hole be there?
Post by: Bitsa (Ralph Wright - RIP) on October 17, 2014, 07:35:01 PM: Drew
Amazed found CD pay the post and its yours I will never need it again,Can not see anything so think your safe.Image to big for here email your address and will email you with the file Ignore the photo wrong thing.
Cheers
Bitsa
Title: Re: Should that hole be there?
Post by: steven400/4 on October 17, 2014, 07:50:26 PM: is the bottom hole a oil drain and the top a oil feed ?????
Title: Re: Should that hole be there?
Post by: Trigger on October 17, 2014, 09:49:24 PM: The bottom hole is a oil drain for the clutch to the sump. The round hole is only a breather hole. Took mine apart to check :'(
Title: Re: Should that hole be there?
Post by: Drew400 on October 17, 2014, 10:41:47 PM: Gosh... above and beyond the call of duty! thank you. I will approach my top-half rebuild tomorrow with renewed enthusiasm.

Cheers Trigger and all for your help with this.

D.
Title: Re: Should that hole be there?
Post by: JamesH on October 18, 2014, 08:40:05 AM: Top man that trigger,..