Front disc conversion

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Fredsmoggy
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Front disc conversion

Post by Fredsmoggy »

Hi all,

Not long brought a 1968 morris minor.

After some help.

Just brought the front Ford disc conversion. I have installed all except the extra reservoir. Replaced the brake lines to the front from the master cylinder and replaced the master cylinder with new and done the conversion on.

I have tried bleeding the brakes and cannot get any brake fluid to the calipers when I open the bleed valve, the pedal goes right down and nothing.

I know these can be a pain but is there something I am missing and I tried bleeding for an hour with no joy.

Any help or advice would be greatly appreciated.

Thanks Fred
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geoberni
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Re: Front disc conversion

Post by geoberni »

Fredsmoggy wrote: Mon Aug 14, 2023 10:09 am Hi all,

I have installed all except the extra reservoir.

Replaced the brake lines to the front from the master cylinder and replaced the master cylinder

I have tried bleeding the brakes and cannot get any brake fluid to the calipers when I open the bleed valve, the pedal goes right down and nothing.
Hello Fred

Why have you not fitted the additional reservoir? The extra capacity is essential for Discs.

You've said it's a new MC.
What happens when you press the brake pedal with the Calliper Bleed Screw still closed?
Does the pedal still go to the floor?

If it does, I suggest your problem is the same as my experience this weekend with a new Master Cylinder. :roll:
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Basil the 1955 series II

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Fredsmoggy
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Re: Front disc conversion

Post by Fredsmoggy »

Hi,

I have not fitted the extra reservoir as yet but I will. This is a new MC from ESM. With the Leeds screws still closed pedal goes to the bottom with no resistance no matter how many time you try. It is the same with the bleed screw open.

We also undid the rear banjo and still no fluid leaked from the reservoir.

I will have a look at your attachment but unfortunately I have thrown away the old MC.

Thank you for your help.
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geoberni
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Re: Front disc conversion

Post by geoberni »

Fredsmoggy wrote: Mon Aug 14, 2023 1:11 pm
We also undid the rear banjo and still no fluid leaked from the reservoir.
That really does sound like the same problem, the Operating Rod is not actually getting to the bottom of the 'hole' to push the Piston in.
I'm guessing your Operating Rod is adjusted quite near the end fitting.
Probably going to have to remove the MC from the car to check, unless you'd rather fiddle around separating the linkage from the bottom of the pedal, but stick something down the centre, like I did with the Allen Key. If it goes in over an inch below the outer lip, then it's the depth of the hole causing the problem.
As I said over on the Post I made, the new one was almost 1.5" deep, whereas my original was a little under 1".
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Bill_qaz
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Re: Front disc conversion

Post by Bill_qaz »

Fredsmoggy wrote: Mon Aug 14, 2023 1:11 pm
We also undid the rear banjo and still no fluid leaked from the reservoir.

If you undone the rear banjo fluid should drip out under gravity or the master cylinder has never filled it bore, so as suggested the piston is not moving or no vent in the cap.
With cap removed push the pedal a few time and look is the fluid moving/agitating? If not then the piston is most likely not being pushed, if you have movement pump pedal with banjo slackened to bleed master cylinder 1st.
Regards Bill
Fredsmoggy
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Re: Front disc conversion

Post by Fredsmoggy »

Hi All,

Thank you all for your advice. We have now got the brakes to bleed and lovely firm pedal. After a quick test drive the brakes are fab. Will go out a few more times to bed the discs in.

Once again, thank you all for your advice.
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svenedin
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Re: Front disc conversion

Post by svenedin »

Fredsmoggy wrote: Tue Aug 29, 2023 3:09 pm Hi All,

Thank you all for your advice. We have now got the brakes to bleed and lovely firm pedal. After a quick test drive the brakes are fab. Will go out a few more times to bed the discs in.

Once again, thank you all for your advice.
Great to hear it is fixed. What was the solution?
1969 1098cc Convertible “Xavier” which I have owned since 1989.

Stephen
Fredsmoggy
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Re: Front disc conversion

Post by Fredsmoggy »

We could not get enough stroke on the pedal, so disconnected the pedal and used a spanner to push the plunger in the master cylinder and that worked. Bleed the whole system then connected the pedal and have a lovely pedal now.
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geoberni
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Re: Front disc conversion

Post by geoberni »

Fredsmoggy wrote: Tue Aug 29, 2023 5:59 pm We could not get enough stroke on the pedal, so disconnected the pedal and used a spanner to push the plunger in the master cylinder and that worked. Bleed the whole system then connected the pedal and have a lovely pedal now.
So have you now adjusted the operating rod to an appropriate length with the correct amount of free play as per the manual?
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Fredsmoggy
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Re: Front disc conversion

Post by Fredsmoggy »

Hi adjusted the brake pedal as per book and the moggy drives and stops on the button.

Once again guys thanks for your advice.
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