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Discussion Starter · #1 ·
After replacing my wheel bearings and greasing my ujoints, I suspect a cold squeal around 30mph + is coming from my motor. I have a Kostov 11, and I'm struggling to find if the bearings are greasable or if they simply need to be replaced. Once the car is moving for a few minutes the squeal stops. It also only squeals in cold weather, which is why I've only recently noticed.

Anyone have any ideas?

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After replacing my wheel bearings and greasing my ujoints, I suspect a cold squeal around 30mph + is coming from my motor. I have a Kostov 11, and I'm struggling to find if the bearings are greasable or if they simply need to be replaced. Once the car is moving for a few minutes the squeal stops. It also only squeals in cold weather, which is why I've only recently noticed.

Anyone have any ideas?

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How much Km on the motor?
I have changed my bearings once at 60000km. I use ACIM motor.
Nothing special required. Well maybe a puller....
Bearings are some 11€ each. Use bearing with rubber seal if possible.
 

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Discussion Starter · #3 ·
How much Km on the motor?

I have changed my bearings once at 60000km. I use ACIM motor.

Nothing special required. Well maybe a puller....

Bearings are some 11€ each. Use bearing with rubber seal if possible.
The motor was supposedly unused when I got it, but the seller was pretty scammy so I have no idea. I've only put about 1,500 miles on it.

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Think about what happens when it heats up. The grease will thin out and flow easier. The race and other bits may expand too.

So it might have dirty grease or be a bit dry, so the grease really needs to heat up and thin out to do anything.

Or it could be worn out and bits are rubbing until they've expanded.

Or it might have some debris in there that settles and has to be squished back out of the way?

It's not hard work, or expensive work, so any time a bearing has an issue I think I'd just replace it. Even if it is low on grease or the grease is dirty, maybe that's because the seal is bad, or the races are uneven, or who knows. Especially since it's a repair that has no emergency and you can pick your time, I'd queue it up for eventual maintenance.
 

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Hi jb,

Most motors of this type use bearings lubed for life, high temperature grease with high temperature seals. Typically no service on bearings required. They are normally replaced when the armature is serviced or if the bearings are somehow damaged. Never reuse a bearing. Disassemble and install properly with proper tools.

The noise may be coming from the brushes and commutator. Cold and the lack of humidity can alter the film on the comm surface. A little run time and heat from friction quiets it. Not sure what to do about it. Turn up the radio. Keep an eye for brush dusting or rapid wear.

major
 

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Discussion Starter · #6 ·
Hi jb,



Most motors of this type use bearings lubed for life, high temperature grease with high temperature seals. Typically no service on bearings required. They are normally replaced when the armature is serviced or if the bearings are somehow damaged. Never reuse a bearing. Disassemble and install properly with proper tools.



The noise may be coming from the brushes and commutator. Cold and the lack of humidity can alter the film on the comm surface. A little run time and heat from friction quiets it. Not sure what to do about it. Turn up the radio. Keep an eye for brush dusting or rapid wear.



major
That is good to know. I have not disassembled one of these motors, so I would have to do some research before doing anything with the bearings. Ita very cold and dry here in Colorado some days, so that would make some sense. What is a good temperature for the commutator? I may bring change the temperature on my fan controller for the electric fan on the motor.

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0 - 100°C. Just a guess. Never thought about it like that. Usually it's cooling at upper limit, like 200°C.
 

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Next time you order a EV motor make sure you order zerk fittings used for lubrication, , my self I ordered of the shelf, not sure why oil lubrication fittings are not standard on the main bearings.
 
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