Mr Grumpy Brake Disc Kit

[RobThomas]

They seem to be a generic design with different locations for the pipework holes. I found them cheaper if I looked for Herald calipers instead of Marina.

[bob1]

Thanks Declan. I've taken the plunge and order the kit from ESM.

[neilmorey]

Noticeable improvement after 100 mile run around East Lothian last weekend. No servo so still requires a good shove but I'm very happy with how they perform.
MOT tomorrow so hope the tester like them too!

[bob1]

My kit arrived today. Very fast delivery from ESM. I see what you mean about the instructions Neil. It looks like parts of them have been cut off by compressing the page down to size. I'm on nights this week so no chance to start fitting the kit until next week.

[simplysimon]

Hi, could you tell me where the 8 plain washers go?
Contacted ESM, who didn't know, then tried the workshop and found out they where not part of ESM, and they told me
they only fit the ford kit. so at present none the wiser.

[philthehill]

The qty 8.......3/8" plain washers go between the back of the swivel & the nyloc nuts fitted to the reduced thickness head bolts that attach the caliper mounting bracket to the swivel.
The reduced thickness bolt heads are required to allow clearance between hub and bolt head.

http://www.morrisminorspares.com/brakes ... ed-p829453

[simplysimon]

Thanks, can get on with fitting the kit now

[neilmorey]

Sorry that all the images in my original posts have disappeared but Photobucket wants me to upgrade my account at a cost of $399 to permit hosting on 3rd party forums.
I'm not willing to spend that amount obviously but if anyone knows an alternative image host I'm happy to amend the links in the original posts.

[washer-bottle]

The qty 8.......3/8" plain washers go between the back of the swivel & the nyloc nuts fitted to the reduced thickness head bolts that attach the caliper mounting bracket to the swivel.
The reduced thickness bolt heads are required to allow clearance between hub and bolt head.

http://www.morrisminorspares.com/brakes ... ed-p829453

Does anybody know of a supplier for these bolts with reduced thickness heads please?

UNF 3/8" x 1" bolt with a head that thickness of 3/16?
Head is 9/16 AF.

Are they 8.8 steel and torqued to 40 lb ft?

Thanks
Al

[philthehill]

Caliper adapter bracket bolts are torqued to 35 - 42 lbf ft.

The caliper mounting bolts are torqued to 50 lbf ft.

If I can find the box containing the spare adapter bracket bolts later this morning I will check the grade of bolt (if specified) and report back on here either way.

If not specified 8.8 should be the minimum grade used.

[philthehill]

Up date on the above post>

The original BL caliper mounting bolts are not marked with a grade i.e. 8.8 but have either of the following markings:-

L8 S

or

GKN T

The thickness of the bolt head is 5.3mm.

If the correct bolts are not available I personally would use at least tensile strength 8.8 bolts with the heads either machined (preferable) or ground down to 5.3mm thickness.
The unthreaded section under the head is 10mm long.

Here is a link to suitable high tensile bolts for your application but they may have to be fettled to fully suit.

https://www.ebay.co.uk/itm/UNF-3-8-Fine ... fz7FaUjU0Q
The original bolts are zinc plated.

I hope that the above is of help.

[IslipMinor]

'R', 'S' and 'T' were the common high tensile grades for imperial bolts and setscrews.

'S' is a little lower in tensile strength than the current '8.8' and 'T' is identical. The link shows bolts to the US spec of Grade 5 (not S), which is also identical to the metric 8.8.

50 lbf. ft. is high for a 3/8" bolt, so make sure that the correct grade HT bolt is used!

[philthehill]

Richard
Thank you for the explanation as regards the markings on the top of the bolts.

Looking again at the bolt heads the letter is a S.

The caliper mounting bolts (qty 2 per caliper) are 7/16" UNF and are torqued to 50lbf ft.

The caliper adapter plate bolts (qty 4 per adapter plate) are 3/8" UNF with reduced heads.

Phil

[IslipMinor]

Phil,

The reference I made to '5' and 'S' is in the Ebay link - the listing header description says they are 'S' and the body description says they are '5'! I would expect the original bolts will be 'S' or 'T'.

50 lbf. ft. torque for a 7/16" UNF bolt is quite normal.

[washer-bottle]

Thanks Phil & Richard

My original Grumpy bolts are T rated (8.8) and have heads 5.5mm thick.
Unthreaded is 7mm, threaded is 16mm, length 23mm.

Al

[IslipMinor]

Al,

Reverting to your original question about reduced head thickness. If you have some new HT bolts and need the head reducing in thickness, I can do that very easily in the lathe - the plating will of course be removed from the head in the process!

If you are anywhere near Oxford, I can offer a 'while you wait' service, but otherwise if you pop them in the post, I will send them back to you by return.

[Sleeper]

Ditto

Location,Location.Location...

I am in Manchester and also have a small lathe..

John

[philthehill]

The heads of the four 3/8" UNF bolts are near impossible to see when the brakes including the stone shields are assembled and the wheel fitted so a lack of plating on the head of the bolt matters very little and anyway they will soon be covered in brake pad dust and road grime.
Below is the view from above without the stone shield.

100_1823.JPG (1.57 MiB) Viewed 2292 times

[washer-bottle]

Thanks for your kind offers. Tomorrow I am going to try and clean up my old bolts by running them through a die and use new nylock nuts and threadlock. Not ideal, but I am running out of time to get back on the road and a MOT.

I have only managed to find machine screws so far, but not bolts (part threaded).

I am near Cirencester and a run out to Oxford to drink tea and spin lathes sounds very tempting Richard, ... maybe once I am able to drive by Morris again.

I found this website a bit too interesting!

https://www.fastenerdata.co.uk/fastener-grades

Al

[philthehill]

For cleaning up a thread the use of a die nut is best as then you cannot undercut the thread profile. Die nuts are produced to a master thread profile.
If you have an adjustable split die make sure that the die is a snug to loose on the thread - try it on a new or serviceable bolt to be sure it is a snug fit but not so snug as to remove metal. Adjust the split die to suit as necessary.