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pneuhyde
Hi All,
I am trying to install a new 914 rubber MC upgrade kit and am having trouble with the orings in the kit that I assume go on to the fittings to seal at the connection to the master cylinder. Whenever I tighten the fitting it squishes the oring out the side. This is not surprising to me because I have a hydraulic background and know that in hydraulic oring boss fittings the inside of the top of the female thread is chamfered to allow the oring to crush down into the hole and it is then sealed on the top by the fitting. In a metric system that has a flat surface like this cylinder has you use a copper crush gasket for a seal or an oring with a metal ring around the outside that holds the oring from squishing out when tightened.
I would like to hear from people who have installed them and how they solved the oring seal issue - if it was needed?
I have also watched Ian Karr's youtube video and he does not address it...and also, as he admits, the video is done without the front end in place so not near the same view and space as my real world efforts.
Any help will be appreciated.

Thank you,
Steve
sixnotfour
Here is a thread addressing the issue;
http://www.914world.com/bbs2/index.php?s=&...t&p=2755766
@Mikey914
Mikey914
These were not designed for pressure. A simple finger tight + 1/4 turn will seal them. The biggest problem we have seen is folks like to over tighten. PM me your address if you need me to ship you out a new oring.
Id be happy to trade you out to a stock if you prefer.
pneuhyde
QUOTE(sixnotfour @ May 25 2020, 05:36 AM) *


Thanks for the thread link. some usefull info.

Steve
pneuhyde
QUOTE(Mikey914 @ May 25 2020, 09:17 AM) *

These were not designed for pressure. A simple finger tight + 1/4 turn will seal them. The biggest problem we have seen is folks like to over tighten. PM me your address if you need me to ship you out a new oring.
Id be happy to trade you out to a stock if you prefer.


Thanks for your reply and I appreciate the feedback and offer to replace, but I have already cut the metal off the plastic tubes and would really like to make this work instead.
I do understand that this is a no pressure gravity feed system, and I don't think I ruined the oring as I only tightened it enough to see what was going on and then I stopped working on it, preferring to ask before going further, hence part of my frustration. Along with having the grommet pull out of the hole when I pulled out one of the plastic tubes far enough out to cut the metal tube off.

I will think a little on the fitting as my worry about not tightening the fitting is it backing out with vibration, but in hind sight maybe it can't back out because the attached hose won't let it turn or move? My other thought is a copper washer but I don't know if the top surface of the port is machined or not, as it is in my shop and I am not right now.

Anyway, Thanks again for your support and response. I, like many here, appreciate what you bring to the table for the 914 crowd.

Steve
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