Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Centre wheel nut very hot

Just wondering if anyone can suggest likely cause please. Arrived back from a 40 mile drive cross country this afternoon and noticed the nearside rear wheel centre nut was extremely hot, felt the hub and it almost burnt my hand. I also noticed the car does not roll freely on a gentle slope as it used to. Any thoughts on like cause appreciated.

Thanks

Sounds like rear brake is binding.

Could be a problem with the self adjusters, or a sticking brake cylinder or possibly a handbrake cable issue.

Assuming no LSD chock other wheel and with handbrake off jack up offending wheel then try turning it.

If it's stuck or very stiff it's likely the brake shoes are binding as suggested by TBM. Unlikely given the age but a worn bearing would give a gritty feel when turning and would have given some audible groaning when driving. Assuming brake issue though, car is out of warranty and you want to tackle the problem yourself you will need to remove brake drum to investigate.



The picture shows my Roadster rear but yours will be similar. The four ¼" UNF hex head setscrews need to be removed first. Ignore the larger slotted head screws, they are not relevant. Problem then will be removing drum if it's jammed on. This wiil likely be for one of the three reasons TBM suggests. If its not handbrake cable it may be an over enthusiastic auto adjuster. I believe there is an access hole on backplate which needs to be aligned with auto adjuster to allow freeing off same with screwdriver. More advice from GoMog here particularly with regard to handbrake cable adjustment which should be done last after brake re-assembly.

Once you have drum off it will be obvious which is the culprit.

Sounds like the brake or maybe the bearing.

Most often the cause is a seized brake cylinder, especially on the nearside which is more subject to going through puddles. However, it does seem rather young for that to happen, unless it doesn’t get used regularly? It will be essential to release the auto brake adjuster first to get the drum off but I expect it will still be a bit of a struggle. If the cylinder is the culprit, the linings may also need to be deglazed and the drums checked for trueness. It would also be wise to inspect & repack the wheel bearing grease as well as it has suffered extreme heat.

Not much use speculating, pop off the brake drum and find out.

As suggested, binding brake shoes are probably the cause.

You haven't told us what year and model Morgan you have which isn't very helpful given there are various types of rear brake setups, each with their various foibles.

Likely cause could be a seized wheel cylinder, seized adjuster, broken return spring, broken hold down spring, detached brake linings

Arwyn

In his signature - 2019 Ivory Plus4

I don't think the signatures show up if you access the forum by phone.

Many thanks for your replies - the car has been pretty well used having done c10,000 since new and given no issues until now. As it is still well within the extra 3 month warranty Morgan gave at the start of the C19 pandemic and given the likely issues may not be easy to fix given my limited garage facilities I think this time around I will be best off taking it in to a dealer to sort out. Once again thanks for the advice.

I have my phone and tablet browser agent set to Desktop. That way you always get the full version of any website although accept you may need to zoom a little more.

Common fault, happened to my +4 at about 15k, seized wheel cylinder. Just replaced again at 44k

Has anyone tried getting the pistons converted to stainless ? If so was the cylinder life improved?
Have been thinking of getting a set made up. Mine must be about to fail again even with 2 yre fluid changes.
(Were seizing every 2 -3 yrs when car not being driven much. Now a daily driver so fingers crossed)

I just drive the car & then the seals fail. :banghead

AlyMatt, this is a photo of your drum brakes to help

The auto adjustment ratchet / pawl mechanism is situated just below the marking of Y47 you can see, there is a corresponding access hole in the backplate, pop a narrow screwdriver in & gently lever the teeth apart and it should allow the shoes to retract, otherwise the drum will be a bu66er to get off

Indeed it is becoming ever more common in trads. When I was last at Techniques, James was saying that rear wheel cylinders have almost become a service item for cars that are not being used for long periods.Expensive too at MMC prices.

The issue is made much worse if the handbrake is applied during these periods of rest , because the exposed part of the pistons corrodes and eventually won't slide inside the cylinder , stainless sleeves will obviously help here, and this is the route I would take rather than stainless pistons. Leave the car in gear , or with chocks if it is not being used.

I now back off the adjustors, remove the drums and have a good look at the cylinders at each service. I also find it is worthwhile to deglaze the shoes lightly. I inspect the pistons for any sign of corrosion and use brake grease on the exposed metal surfaces under the rubber caps.

In light cars like ours the rear brakes do not provide much of the stopping power, so the pistons don't move much at the best of times (competition cars excepted of course) so it pays to keep a watchful eye on them.

On my android phone no signatures show even on desktop if you're signed in. If I'm not signed in they do show!

Excellent advice from Andy as always, but this bit always amuses me when I see it. It's standard advice, I see it a lot, but I do find myself wondering just how many Morgans are kept in garages with sloping floors? All our cars just sit in the garage in neutral with the handbrake off, I've never noticed them rolling anywhere

Obvs for those that have to live outside parked on a hill, it's different kettle of poissons. In gear with the front wheels pointing downhill and turned towards the kerb would get my vote.

Depends how free rolling the car is Tim. I lowered mine from ramp onto scaffold boards, themselves on laid concrete garage floor (essentially flat) and it promptly rolled backwards somewhat to my surprise

That's very strange Gordon. Can only imagine it's some privacy setting on your account causing it to only happen when signed in?

There's a bit in 'Preferences' where you can select if you see signatures or not.

Many thanks for the picture and further advice, it will be interesting to see what the issue is as the car had been regularly used (at least once/week) since new and always left chocked and handbrake off at home) with 10k miles over the 2 and a half years since new..