I put a tee in the master cylinder cap and re attached the original vent metal line. The other side goes to my new remote reservoir. I see that that small original vent line attaches to a large tee and then goes to the booster. My questions are:
1. Is there vacuum or pressure or nothing in that small vent line?.
2. Am I going to pressurize the remote reservoir? I don't think that would be good.
3. Do I need that OE small vent for the brakes to function properly?.
4. If not, why is it there, what does it do?.
5. Do you foresee any problems using this tee setup?.
6. Thanks for any input.
1. the vent line is just that - it allows to equalize pressure between the inside of the MC and the ambient air.
2. no, but you may allow fluid from your new reservoir to travel along the vent line when the MC is full. The cap on your new reservoir is vented, so any additional venting at a lower level is not helping and may be counterproductive.
3. NO
4. to ensure you do not build a vacuum or pressure in the MC due to fluid level and ambient air pressure changes; many MCs received a ''mushroom vent'' similar to those on the axle housings as an alternative to the vent line. These vents sort of work, but can allow a vacuum to build, which leads to brake malfunction (and should be removed).
5. Yes. You cannot use a pressure bleeder directly on your new reservoir (would blow right out by the vent line) and, as I said above, I would be concerned about expensive silicon brake fluid travelling along the vent line to places no brake fluid should ever aspire to go.
I would remove the T and leave the vent line disconnected. No harm in doing that. Ensure that the cap on your new reservoir is vented. All you need is an airtight connection between the MC cap and the new reservoir.
