420G bleeding brakes


Is it possible to bleed the brakes without jacking up the car?

The front left reservoir was lower and brakes very soft and not functioning after starting her up


Difficult on the fronts but possibly doable. Rears very doubtful unless there is access to the inboard calipers via port holes under the rear seat, I don’t think there is one there though.
Best to do it properly and jack up and use axle stands.

Thanks Robin,

I am just apprehensive as the jacking points are not especially solid… Any other areas you might recommend as alternatives?


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Get some ramps. I prefer to raise the front and rear of the car separately and put ramps beneath all the wheels to raise the car for work. In this way I have safely removed and replaced engines, transmissions, exhaust systems and rear brake components.
I also have a four post lift, but ramps are better for some work and they are more affordable than getting a lift.



WHat kind of weight rating should I look for?



for ordinary vehicles is fine 420G weigh ~ 1830kg

must be low profile, as a 420G will not drive forward onto regular sloped ramps

I don’t drive my cars up onto ramps any more. I much prefer to use my floor jack to first raise the rear end high enough to slide the ramps beneath the rear wheels and then raise the front end high enough to slide the ramps beneath the front wheels. This technique removes a lot of the excitement and uncertainty of driving car up onto ramps and puts the car and ramps exactly where I want them.
Of course if you are just working on the rear brakes, raising the front end may not be necessary. I like to have plenty of room to work safely beneath a car. I have four ramps and a bunch of jack stands so I typically raise the entire car for ease of working on it, and it only takes a few minutes more to put the ramps/jack stands on all four wheels rather than just two.

I don’t own a 420G but I have successfully used this technique to put my MK VIII, E-Type, XJ6s, XJ12, and XJ-S up on four steel ramps safely. I have had problems with the steel ramps sliding on concrete floors and only use the floorjack technique now to raise the cars onto ramps. It is much more precise and gentlemanly. :wink:


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that is good advice

420G is not the easiest car to lift, as the original jack places leverage on the jacking points

I usually use the actual reinforced jack point to lift with a trolley or bottle jack, and can just squeeze an axle stand next to it

You cannot bleed the rear brakes without raising it, nasty job…@ the OP…I would not start by bleeding the rears without a good reason

I’ve successfully used a series of 2x6 blocks about 18 inches long to raise a car enough to get under to do some maintenance. They can be pretty stable and do not require any specific weight rating. Block the car so it can not roll, however.

Thanks everyone for the advice… I will hope to do something over the weekend… Currently brakes have no real function at all … brake pedal just depresses and rises without hardly any resistance.

Any other areas to check?

make inspection if any leaks under car, especially rear hose, old metal lines can rust through to, especially the one routed all around under the radiator

a “common” problem is the master cylinder seals go spongy, and allow fluid to bypass into the booster.

Typically, they may go the floor, but “work” sometimes if pumped

there will usually be some evidence of fluid leaking at the base of MC/booster junction if this is the case

the 2 nuts can be loosened, and ease forward the MC, if its a mess in there, MC seals need renewal

How old are the seals in the Master cylinder…they should be renewed occasionally

Might as well install this easy to get to kit:



Thanks, yes these will be great once I get to the rears…

BTW, is this ramp a good fit?

I will search for a leak from suggested areas over the w/e

THanks again


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Ramp! https://www.amazon.ca/dp/B0117EETEK/ref=as_li_ss_il?slotNum=10&keywords=car+ramp&ie=UTF8&sr=8-3&linkCode=g12&linkId=bea7529448246c694b260629d5bb5f3b&imprToken=5f9wwwTJKl1y.9yfsvjzrw&creativeASIN=B0117EETEK&tag=dan03890d-20

That link just goes to a home page on amazon?

12,000 lbs should just be capable I suppose at a push :slight_smile:

Hi …Did not attempt to bleed the brakes… however have not found any dripping at all and still no pressure at pedal. I want to take a quick look inside the booster but can anyone inform regard how to remove the

White connection. Unsure if it screws out of need to be persuaded otherwise! If anyone knows please let me knows


Its just a barbed fitting which will need to be prised out.

Perfect, I’ll give that a go later and see what may be occurring in there…
Any obvious reg flags that I should look out for?