KIMI 3 - Series 3 FB

[Casey]

I went around cleaning around all the hose fixing areas to help prevent dirt from getting into the system later, then squirted penetrating oil on all the fixings and left this to soak in overnight.

The next day I applied another dose of penetrating fluid to all the fixings and then started on the front passenger side by removing the spring clip holding the centre hose support to the bracket on the suspension strut. The hose can then be freed by jiggling the hose support forward, then down through the notch in the bracket.

(Driver's side shown)

[Casey]

The next step was to crack the flare nut on the bulkhead bracket and the hose into the caliper. Using a good quality flare spanner was essential, as the years of exposure to road grime had created quite a bond between the hose and the flare nut and they were reluctant to part. Once both had been cracked, I unscrewed the flare nut completely, capping the end with a bleed nipple cover, which successfully stopped it dripping. The spring clip can then be removed (tapping with a screwdriver and hammer needed!), and the hose fixing pulled out:

[Casey]

The HEL hoses look to be well made and are a close match in length the OEM hoses. The only perceptible difference is that the front hose are about 3-4cm longer, which shouldn't present an issue. I will carefully check for any possible rubbing or snagging after fitting. Here are 3 of the 5 hoses; front, rear and axle mount. Fresh copper washers are provided.

[Casey]

The centre support on the HEL line is not fixed, but can slide along the hose. There are some plastic clips provided to attach both sides of the hose. When in position, these restrict movement. Instructions for positioning/fixing these "stops" this are provided with the hoses.

[Casey]

One snag arose in fitting the front hose into the bulkhead mounted bracket - the HEL fitting was about 0.5mm larger than the hole in the bracket. This required the use of a Dremel grinder to take off a very small amount of metal. After that, the new hose was bolted with the new washer onto the caliper, the centre fixing fitted to the strut mounted bracket and the other end fitted with the spring clip into the slightly enlarged hole on the bulkhead bracket. The existing flare nut screwed easily into the new fitting, just requiring a bit of a careful clean up of the few ml of fluid that inevitably was lost in the process.

The last step was to fit the spring clip into the centre mount and check the hose position by turning the steering wheel to both extremes before affixing the two plastic "stops". I'll need to re-check for clearance when the suspension is compressed later.

[Casey]

Removing the rear brake hoses was pretty much the same process as for the front EXCEPT the position of the hard line flare nut is such it has had full exposure to the elements for nearly 40 years, so the hard line had "fused" onto the flare nut. So, although the nut (surprisingly) was relatively easy to free from the thread in the hose, the hard line twisted with it 

This was the same for both sides. Also, the 5th hose would not come free from the T splitter on the axle - the other end is in a shielded position and looked like new and easy to remove. I therefore decided the best option was to cut the two rear hard brake lines and re-make them.

[Casey]

The new rear hose went on easily.

[Casey]

Freeing the 3 fixings into the very rusty "T" splitter mounted on the axle was not easy. I was about to resort to heat but tried one final time with the T firmly in a vice and a 6 point 17mm long spanner on the hose nut when gentle persuasion of a lump hammer finally freed the connection. Penetrant had been soaking in there for days with little effect it would seem.

Just for reference (handy when you find yourself on the floor with the wrong tool to hand ) the caliper end fixing nut on the OEM hoses is 17mm and the HEL ones are 14mm!

The other two flare nuts in the T were also reluctant to free their grasp, so I cut the pipes close to the nuts so I could put on a 6 point 10mm socket. They surrendered fairly easily when faced with this attack

[Casey]

T splitter de-rusted and sprayed before re-installing, together with replacement s/steel 6mm bolt.

[Casey]

Something to mention if you only re-make brake flares occasionally. There are basically 2 main types of brake union flare nuts. The pics below show the type required for the RX-7 on the right. It has a 45 degree chamfer on the inner edge to correctly seal the inverted/double flare used in the RX-7 calipers and fittings. The other type (with the "shoulder") is for use with bubble flares and won't correctly seal to 45 degree seats.

 

[Casey]

All hoses and hard lines now fitted. There is obviously still masses of air in the system, but I still had a full reservoir and will be changing the master cylinder next, so decided to give the pedal a few gentle pumps to see if it revealed any leaks. Yes, it did! Both rear hose-hard lines leaked (all the rest OK), so I tightened nipped them up a bit more (not wanting to over-tighten them when I first installed them). A few more pedal presses showed no further signs of leakage anywhere. I will check again when the master has been changed and the system bled.

Typical flare on new lines - looked OK to me 

[Casey]

Passenger side hard line finished. I drilled and tapped a 4mm thread in the sway bar mount to add a new P-Clip as the old one was shot.

The rust is a job for another day!

[Jamie R]

Super job Malcolm,

[Casey]

Super job Malcolm,

Thank you, but nowhere near to the level of your awesome projects Jamie!

[Casey]

Installing the new brake master cylinder was very straightforward.

First task was to bench bleed. I had the kit mentioned in a post above, which enabled two ports to be bled, so I made up a something to bleed the 3rd port. In practice, the nearest two ports bled fairly easily, but they then required to be blocked off to bleed the furthest port easily. I simply used some "Sealey" brake hose clamps, which I already had in my tool collection. Once bled, I used some bleed nipple caps to prevent fluid leaking everywhere.