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Wheels Too Hot To Touch


Best Answer detroitmini , 17 October 2019 - 03:42 PM

Well, idk how, but this topic can be marked as solved. Took the vehicle for a long test ride last night and the wheel is no longer blazing hot.

 

Root Cause: Dragging brake shoes

 

Solution: Since vehicle is Canadian spec, has inertia brake valve under rear subframe. Valve was not mounted nor plumbed properly. Valve was remounted with brakes line rerun.

 

Thank you everyone for the help/conversation!

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#16 detroitmini

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Posted 17 September 2019 - 02:39 PM

I replaced the drum on the corner. Still getting hot.

 

I turned out the adjuster. Still getting super hot.

 

I'm stumped. For some reason, my front and rear separated system (know is true due to one pipe running from front to rear) is acting like a diagonal split system. Front Left and Rear Right super hot and Front Right and Rear Left cold. How could this be?



#17 cal844

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Posted 17 September 2019 - 02:46 PM

Could it be sticky wheel cylinders or pistons?

#18 detroitmini

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Posted 17 September 2019 - 04:01 PM

Replaced wheel cylinder so I hope a brand new wheel cylinder isn't sticking.



#19 detroitmini

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Posted 10 October 2019 - 12:46 PM

Pressed brake pedal and wheel is LOCKED. Loosened line to replace flex hose and wheel freed up showing it is a pressure relief issue and not metal to metal binding. Replaced the flex hose cause I had one to rule out collapsed hose internally. Retested by pressurizing system. Wheel is still locked. Therefore, I am not getting the relief through the proportioning valve or the brake master. The master feeds both sides through the one rear line while the proportioning valve feeds each separately. Since I only see this on right side and not left, I am thinking the proportioning valve.



#20 cal844

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Posted 10 October 2019 - 12:49 PM

You can bypass the proportioning valve to test that is the fault.

#21 Curley

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Posted 10 October 2019 - 01:14 PM

You can bypass the proportioning valve to test that is the fault.

 

In my day we threw the bias thingy on the rear subframe (and later the thingy on the front bulkhead) in the bin!



#22 Benoit_Dupont

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Posted 10 October 2019 - 01:28 PM

maybe a stupid suggestion, but:

 

if you can spin the drums with no wheels on it then your are sure that it does not come from there.

 

So are we actually sure it comes from the brakes ? I mean: after a little ride, if you can't touch the tire but CAN touch the drums then maybe wheels are rubbing somewhere on the body when you sit in the car, but are clear when the driver gets off the car?

 

did you change wheels recently ? or ride heights ? 



#23 cal844

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Posted 10 October 2019 - 02:32 PM


You can bypass the proportioning valve to test that is the fault.


In my day we threw the bias thingy on the rear subframe (and later the thingy on the front bulkhead) in the bin!

Retroman on here does a kit that uses the earlier proportioning setup, replacing the FAMwtf valve

#24 Ethel

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Posted 10 October 2019 - 02:37 PM

Are you sure you've fitted all the shoes correctly? Drum brakes have a self servoing action:

 

2014-10-17%2B12.38.46(2).jpg

(Photo pinched from: http://waynesminipro...used-shoes.html)

 

Note also the pull off springs, they're important for the same reason.

 

If it was a hydraulic fault cracking open the bleed nipples on the offending corners seconds after releasing the pedal would release any residual pressure and free the wheels.

 

You could also go for a short drive and frequently stop to feel for heat build up, that might reveal where it's being generated, e.g. if the grease caps were hottest that would suggest wheel bearings.



#25 detroitmini

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Posted 10 October 2019 - 03:47 PM

S

 

maybe a stupid suggestion, but:

 

if you can spin the drums with no wheels on it then your are sure that it does not come from there.

 

So are we actually sure it comes from the brakes ? I mean: after a little ride, if you can't touch the tire but CAN touch the drums then maybe wheels are rubbing somewhere on the body when you sit in the car, but are clear when the driver gets off the car?

 

did you change wheels recently ? or ride heights ? 

 

Yes I am sure it is the brakes. Last time I had the wheel off and pumped the brakes a few times to lock the hub up. So it was locked without anything rubbing/tire on. Then, I cracked the brake line to release pressure and it freed right up.

 

 

 

You can bypass the proportioning valve to test that is the fault.

 

In my day we threw the bias thingy on the rear subframe (and later the thingy on the front bulkhead) in the bin!

 

 

Mine has the proportioning valve on the rear subframe with one line running back.

 

You can bypass the proportioning valve to test that is the fault.

 

I might run by the hardware store to get a T to test it out. Or switch left and right to see if it follows.

 

Are you sure you've fitted all the shoes correctly? Drum brakes have a self servoing action:

 

2014-10-17%2B12.38.46(2).jpg

(Photo pinched from: http://waynesminipro...used-shoes.html)

 

Note also the pull off springs, they're important for the same reason.

 

If it was a hydraulic fault cracking open the bleed nipples on the offending corners seconds after releasing the pedal would release any residual pressure and free the wheels.

 

You could also go for a short drive and frequently stop to feel for heat build up, that might reveal where it's being generated, e.g. if the grease caps were hottest that would suggest wheel bearings.

 

Yes. Checked this a million times as I was not confident in myself the first time.



#26 Moke Spider

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Posted 10 October 2019 - 04:43 PM

I'm wondering if this is the Master Cylinder ?

It maybe just the way it's mounted / fitted that's at issue.

 

You should be able to do this in the garage. Check the line coming out of the master cylinder will undo (just 'crack and then close it). Get the Brakes to Lock and then quickly 'crack' the line at the master cylinder. If you get a spurt of fluid then it's a Master Cylinder Issue.

 

When The Master Cylinder are fitted up, it is critical that the Push Rod Clevis and the Brake Pedal are both clear of the body when at rest, ie, the Pedal should 'hang' off the Push Rod. If it does not, then at rest the ports allowing the fluid to return will always be covered over. Because if the shape and design of the seals in it, as you drive and with normal road vibration, it slowly pumps the Brakes on and the seals act as a one way valve. I can't recall if these were used in UK production, but there are shims available to pack out the Master Cylinder.

 

If  it's not this, then The Master is likely at fault. The Seals can swell causing the same ^ and or the Residual Pressure Valve within it can act up also doing the same ^ .



#27 detroitmini

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Posted 10 October 2019 - 05:03 PM

I'm wondering if this is the Master Cylinder ?

It maybe just the way it's mounted / fitted that's at issue.

 

You should be able to do this in the garage. Check the line coming out of the master cylinder will undo (just 'crack and then close it). Get the Brakes to Lock and then quickly 'crack' the line at the master cylinder. If you get a spurt of fluid then it's a Master Cylinder Issue.

 

When The Master Cylinder are fitted up, it is critical that the Push Rod Clevis and the Brake Pedal are both clear of the body when at rest, ie, the Pedal should 'hang' off the Push Rod. If it does not, then at rest the ports allowing the fluid to return will always be covered over. Because if the shape and design of the seals in it, as you drive and with normal road vibration, it slowly pumps the Brakes on and the seals act as a one way valve. I can't recall if these were used in UK production, but there are shims available to pack out the Master Cylinder.

 

If  it's not this, then The Master is likely at fault. The Seals can swell causing the same ^ and or the Residual Pressure Valve within it can act up also doing the same ^ .

 

I did the pressure relief test to the valve, but not to the master. I will have to try this tonight! Thanks!



#28 detroitmini

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Posted 10 October 2019 - 08:42 PM

Is this the contact u are talking about?20191010-163338.jpg



#29 Moke Spider

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Posted 11 October 2019 - 12:26 AM

Is this the contact u are talking about?20191010-163338.jpg

 

It's only a tiny photo at this end, but yes, that's the general area.



#30 detroitmini

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Posted 11 October 2019 - 12:22 PM

 

Is this the contact u are talking about?20191010-163338.jpg

 

It's only a tiny photo at this end, but yes, that's the general area.

 

 

So I took the master off and lifted it, and even resting on top of the studs (approx 3/4" above normal position) the brake pedal still rests on the body. Do you shim it up? Or rearward in vehicle?






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