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Brake/clutch resevoid replaced do I have to bleed the system

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Goldie

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I have replaced my reservoir. Do I need to bleed both systems.Lines remained attached to MC's. I use silicone dot 5.
 
No, not unless the fluid level in either system fell below that of the hydraulic cylinders.
 
I agree with Michael. If the fluid was still in the lines between the MC and the reservoir then no air could get in. But having said that, if the fluid did by some chance get way down in the line near the MCs then there could be an air trap when you refill the reservoir. If the air is near the reservoir it will perculate out. If it got near the MCs it could get sucked into the MC there-by needing bleeding. This is very unlikely but possible. Pure physics.
 
I lost very little fluid at the reservoir coupling. I never let the open end get below the MC and I asked the question because it seemed to me that air would not get to the MC. Also the reservoir is not under pressure. I will test drive to make sure.
 
yep it's going to be a judgement call but I believe if you have good brakes after you swap the reservoirs and you take it for a ride and you still have good brakes, then you will always have the good brakes. I happen to have experienced this very situation in May of this year. I was checking my Healey over for the trip to the Smoky Mountains and I found the reservoir fittings leaking. Nothing I did would stop the leak so I bought a new reservoir. Popped it on, filled the can and when for a drive. Brakes worked perfectly. I drove it a few more times before I went to South Carolina. Down there I drove for 5 days and covered 1200 miles. Brakes still worked perfectly. Have been out many times since, including this evening for about 3 hours , have never yet bled the brakes. They work perfectly.
 
I drove the car about 10 miles after replacing the reservoir with several stops along the way. Brakes and clutch were basically no different than before. My instinct was that if I kept the lines to the MC with fluid then the fluid would displace the little bit of air at the couplings. I will pay attention to how the brakes and clutch are working. I really don't want to deal with the slave cylinder at the tranny. I can deal with the brakes.
 
Goldie said:
I drove the car about 10 miles after replacing the reservoir with several stops along the way. Brakes and clutch were basically no different than before. My instinct was that if I kept the lines to the MC with fluid then the fluid would displace the little bit of air at the couplings. I will pay attention to how the brakes and clutch are working. I really don't want to deal with the slave cylinder at the tranny. I can deal with the brakes.
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If there was any air in the lines you would have had a spongy pedal. If not, you're good.
 
Steve, just for conversation, If there would be an air bubble between the reservoir and the master cylinder that would not cause spongy brakes because it is not part of the pressurized system. That tubing is just feeding fluid to the MC via gravity. But if air got into that reservoir line it would most likely perculate up and out of the reservoir. Only if the line was almost completely void of fluid would the air in the line have a chance to get drawn into the MC.
 
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