Honda-SOHC

SOHC.co.uk Forums => CB750 => Topic started by: martin_uk on February 22, 2015, 03:36:20 PM

Title: CB750K8 Oil gallery cap and lower crankcase plugs
Post by: martin_uk on February 22, 2015, 03:36:20 PM

These always seem to be chewed up as have quite a shallow hex head.

Thread is 20 x 1.5

Has anyone tried alternatives?

I see there are some sump drain plugs with same thread, allen key fitting seems better, although not original.

Interested in your thoughts  :)

Title: Re: CB750K8 Oil gallery cap and lower crankcase plugs
Post by: martin_uk on March 03, 2015, 06:05:21 PM

I decided to go ahead and order a couple of these as thread is same size as Honda cap and had advantage of magnet to trap metal particles and fairly cheap  ;)

http://www.ebay.co.uk/itm/281523874391?_trksid=p2059210.m2749.l2649&var=580549659651&ssPageName=STRK%3AMEBIDX%3AIT (http://www.ebay.co.uk/itm/281523874391?_trksid=p2059210.m2749.l2649&var=580549659651&ssPageName=STRK%3AMEBIDX%3AIT)

Arrived today and although slightly different to image (head is concave)

(https://farm9.staticflickr.com/8630/16086544563_764586316e_c.jpg) (https://flic.kr/p/qvvKfB)2015_0303eng0022 (https://flic.kr/p/qvvKfB) by nitram2010 (https://www.flickr.com/people/46578358@N07/), on Flickr

Not too keen on reduced section at base of threads as means sealing washer can misalign.

Have ordered up some Dowty Viton washers which I think would work better.

You could not use O ring as does not have retainer groove like original.

(https://farm9.staticflickr.com/8575/16680580756_445b941ff8_c.jpg) (https://flic.kr/p/rq1kvW)2015_0303eng0015 (https://flic.kr/p/rq1kvW) by nitram2010 (https://www.flickr.com/people/46578358@N07/), on Flickr

Magnet is quite strong

(https://farm9.staticflickr.com/8624/16705219651_bf35712478_c.jpg) (https://flic.kr/p/rsbBNt)2015_0303eng0021 (https://flic.kr/p/rsbBNt) by nitram2010 (https://www.flickr.com/people/46578358@N07/), on Flickr

Loosely fitted without washer

(https://farm9.staticflickr.com/8623/16518908808_1b94dcdf96_c.jpg) (https://flic.kr/p/raHJ5y)2015_0303eng0016 (https://flic.kr/p/raHJ5y) by nitram2010 (https://www.flickr.com/people/46578358@N07/), on Flickr

The original has a 14mm head, so presumably Honda did not want them overtightened, so care would be needed.

Not sure if I will fit, but If I do will probably start with top gallery so easier to keep an eye on.