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IVA brake question
ste - 30/7/17 at 05:02 PM

Does my car need brake fluid level senders in both fluid pots? I interpret the IVA manual to say that as long as you can see through the pots which have Max and min on them then that will suffice

Thanks

IVA tomorrow btw!


ste - 30/7/17 at 05:30 PM

Specifically section 09D, required standard 19

19. The hydraulic system must be fitted with a red warning lamp,
sensitive to line pressure and capable of signalling the failure of any
part of the hydraulic system as soon as the brake is applied and
remaining lit as long as the failure exists (with the ignition switched
on). As an alternative, the warning lamp must be sensitive to the
reservoir fluid level, providing the reservoir is directly connected to
supply the pressure side of the master cylinder when the piston is
in the “brakes off” position, so that a failure of either part of a split
system would result in a continuous draining of the reservoir fluid
when the control is released (see Notes 2 and 3)


adithorp - 30/7/17 at 05:43 PM

Yes, you need float switches on both reservoirs.


ste - 30/7/17 at 05:59 PM

quote:
Originally posted by adithorp
Yes, you need float switches on both reservoirs.


But RS16 says

16. It must be possible to check the fluid relative to the manufacturer’s
specified minimum level on all brake fluid reservoirs by the actual
fluid level being visible through a transparent section of the
reservoir, with the minimum level marked permanently on to this
section. As an alternative, a red warning lamp (see Figure 1) must
be capable of illuminating when the reservoir fluid falls to the
minimum level.


adithorp - 30/7/17 at 06:18 PM

It's this part of of the reg' that applies (in particular "EITHER PART" )...

"...As an alternative, the warning lamp must be sensitive to the
reservoir fluid level, providing the reservoir is directly connected to
supply the pressure side of the master cylinder when the piston is
in the “brakes off” position, so that a failure of either part of a split
system would result in a continuous draining of the reservoir fluid
when the control is released (see Notes 2 and 3)"

So if either part of the system starts to lose fluid you'll know while driving. It's no use if you only know by opening the bonnet.

[Edited on 30/7/17 by adithorp]


britishtrident - 30/7/17 at 06:24 PM

All of which means you can have
(1) A differential pressure switch activating a warning light used together with transparenent resevoirs.
Or
(2)Resevoir fluid level switch(es) on both hydraulic circuits with a test switch which can also act the handbrake warning light.

In actuallity (1) won't work on a car with an adjustable pedal balance bar or a stepped tandem master cylinder. The differential pressure switch was used on some late 1970's cars was PITA anyway so (2) is the only practical solution is level switches on both hydraulic circuits.



[Edited on 30/7/17 by britishtrident]


loggyboy - 30/7/17 at 06:25 PM

Whilst it repeating the above, for clarity there are 2 reasons you need a level warning light.
1st is to warn of a level drop if you cannot see the fluid level. But even if you do have a clear fluid resevoir the 2nd requirement is to have a pressure warning system, and the simplest way to achieve this is based on the assumption that if you have low prwssure, that will be down to a leak and a leak will cause fluid level to drop. Hence, as above, you will need one on each reservoir even if you have visible fluid level reservoir.

[Edited on 30-7-17 by loggyboy]


craigdiver - 30/7/17 at 06:50 PM

I was looking at using this (ebay item 271902351148);



The ebay seller claims acceptable for IVA. Is is triple outlet and suits 2xbrake circuits & hydraulic clutch.

Would this help?


adithorp - 30/7/17 at 07:04 PM

Yes, that'll work fine. I'm running 2 circuits of one res'. Make sure there are divisions internally so that if one circuit leaks the other fluid doesn't drain from the good circuit (usually the top of the division is just below the low fluid warning level)


ste - 30/7/17 at 09:38 PM

Thanks for that. Managed to get two level senders off a mate who is a ford breaker at 8pm on a Sunday and fitted them into my fluid pots lids. Luckily I still had the plug tucked away so made a little loom to join two together and bingo, I get the warning light if either one is pressed to test and the light test via the handbrake