Classic cars forum & vehicle restoration.

[Ray White]

A further update today. The oil pressure warning light was actually leaking from the flexible hose; not the union as I had first thought. This means I have been sold yet another faulty new part which will need to be replaced.

The question of the brakes not working is getting beyond my pay grade. The master cylinder and wheel cylinders are all new as is the pipework. The 1.9:1 servo is a genuine Lockheed unit (not one of the super cheapo Chinese copies that are flooding the market) and I have installed everything as best I know how using the correct hose.

If the engine stumbles badly when I apply the brakes, I assume the air being drawn from the servo is interfering with the mixture.???

I may be forced to add an electric vacuum pump; thus removing the engine from the equation.

[ukdave2002]

Are there any valves in the servo air circuit that could either be faulty or fitted the wrong way round?

[Ray White]

[Ray White]

So... I received the hose but unfortunately it has metric threads... when what I needed was BSP. This is what happens when you try to save a few quid. The stainless steel braided hose was advertised as 1/8" which (being an imperial size) led me to assume it was 1/8" BSP. The diameter of the female couplings was the right size for BSP but it has metric threads so will not fit.

In the end I have bought the right part from Octagon Car Club spares...which is what I should have done in the first place.

Will I ever learn?

[Ray White]

Just to add even more angst to this job, the new oil hose from Octagon - while the correct 1/8" BSP fitting - is a fraction too long for the union fitting. As can be seen the nuts (at both ends) on the replacement are longer and presumably will need to be pared back.



It is cold and wet and I am not in the right frame of mind for mucking about... so I have shut the garage door on it.

[Ray White]

I have now ground down the nuts and fitted the hose. No more oil leaks, thank goodness!

I checked the servo by pressing the pedal and starting the car. If the servo was working correctly the pedal would have dropped an inch or so when the engine fired ... but there was hardly any movement at all. If I start the engine then depress the pedal it will immediately stall.

[Ray White]

I have now ground down the nuts and fitted the hose. No more oil leaks, thank goodness!

I checked the servo by pressing the pedal and starting the car. If the servo was working correctly the pedal would have dropped an inch or so when the engine fired ... but there was hardly any movement at all. If I start the engine then depress the pedal it will immediately stall.

[Ray White]

It looks like there is insufficient vacuum to operate the servo. Not only is this because I have a supercharger but I have discovered that my new sports camshaft has greater valve overlap which leaves less time for a vacuum to form.

I have decided to order a vacuum pump and do what I can to quieten it down. Ideally I would have chosen a 'vane' type over the 'piston' version because they are much quieter. (60% less).. but they all seem to be made in America and I need to keep things local. The vane pumps are also without exception described as 'plug and go' and 'vehicle specific'; this means if I cut off the pre wired plugs for my installation ...and there is a problem ... I will not be able to return the pump for a refund.

This video shows the set up of a simple vacuum pump - up as supplied by 'Car Builder Solutions' - so all I need to work out is how best to mount it in the car. I plan on fitting the pump in the enclosed area behind the seat; opposite the servo. I have also ordered a small K&N filter which should help reduce it's noise.
https://www.carbuilder.com/products/electric-vacuum-pump?variant=41978131120182#video-gallery

[alastairq]

Make up an adaptor cable for the pump so you can keep the original pump connections for guarantee purposes, but plug them into the car's loom via the adaptor you've made up?
_________________
Dellow Mk2, 1951 built, reg 1952.
Fiat 126 BIS
Cannon special [1996 registered. Built in 1950's]
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Ford Pop chassis, Ashley 1172 bodyshell, in pieces.

[ukdave2002]

Do you really require a brake servo? It seems like a lot of hassle?

[Ray White]

[Ray White]

[bjacko]

My Morris 8 has similar brakes to the MG's and I find they are pretty good. The way we drive our old cars there is not a lot of usage for the brakes but when you need them they work fine. I find driving with as little brake usage as possible not only saves wear and tear on the brakes it also saves fuel. I learnt during the Suez crisis when we had rationing of fuel in UK.
Of course we are used to our modern cars with servos etc but you cannot compare the two, although some people do and complain about old car brakes.
Whilst I was restoring my 8 I had a 1927 Cowley and they were not the best brakes but you learn to cope with them and make allowances and watch for idiots cutting in on you. Never had any leg aches because they are not used as much, as old cars do not have the acceleration of modern cars.
_________________
1938 Morris 8 Ser II Coupe Utility (Pickup)
1985 Rover SD1 VDP

[Ray White]

I must stress that I am not saying that there is a problem with the brakes. I am now in my 70s and the need for a gentler pedal has more to do with me than the car. When I was younger I wouldn't have bothered but as I get older I will still want to enjoy driving it. The same reasoning is behind a steering upgrade. Importantly, I am not alone as all of my mods have been done many times before.

I liken driving an old car to riding a traditional British motorbike. The salerooms are packed with wonderful old bikes which have just become too heavy for their elderly owners.

[Ray White]

The electric vacuum pump arrived this morning from Car Builder Solutions. It certainly looks good and fitting should be straight forward. A small air filter has been included (which I can fit to the pump exhaust to help reduce noise).

Despite the cold, I ventured out to the garage and started the fitting.

I had previously removed the hose from the supercharger but getting it out of the chassis rail was not easy; even one of the clips in the chassis had to be ground off.!

Eventually I was able to pull the hose out and start thinking about where to cut it. Luckily the pump will sit neatly on the chassis rail on the opposite side to the servo. It's bracket is mounted on four rubber feet - 40mm apart - which means they can neatly straddle the chassis rail. The feet have 3/16" studs that need to be fixed to a firm surface.

To ensure a secure fitting I measured and drilled four holes in a piece of steel plate and attached the feet to the the pump and the plate with the supplied nuts but added spring washers for extra security.

To secure the assembly to the chassis rail without drilling holes in it, I will be fitting two 40mm x 110mm 'square' U bolts. I did this successfully with the servo (on the opposite chassis rail).

I will need to drill four 10mm holes in the steel plate to accept the U bolt threads but when fitted to the chassis it should be perfectly sound.
To help the pump blend with the chassis and axle I shall paint the steel plate gloss black.

Another part that will require fitting is the switch. This has two ports and an electric connection point. It needs to be mounted between the pump and the servo. Conveniently, an existing thread provides a central location.

The electrical supply - which includes a dedicated relay - will need thinking about because it wants to be ignition activated. I had hoped to have finished the electrics but ...such is life.
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