w123 blower motor -- two questions

[Zacharias]

I recently changed my '85 300d blower motor as it was gradually slowing down after running for a few minutes. I swapped it out without thinking about it too much. Shortly after my climate control panel (dash controls) gave out and I changed that unit too.

The replacement used motor runs fine but on cold mornings when I hit bumps before the heater is blowing hot... it makes a LOUD squeal like nails on a chalkboard.

Two questions:

1. What is the issue with the original blower motor that was slowing down after a few minutes? Brushes worn?

2. What's up with the "new" motor? It sounds like the cage is making contact with the enclosure walls... but I examined it before installing and it seemed nice and tight, no play or wobble in the shaft. What is causing the noise? Bearing loose and allowing the shaft to float?

Thanks

[Diesel911]

Was the replacement a new motor or a used motor?

If it was a used motor either the bearings need to be replaced or lubricated.

Also some have Bosch Motors but mine has a Siemans (Seimans?) Motor in it.

[koooop]

Thread hijack here! PO hooked the blower motor up in my '81 240D to the sunroof circuit (fuse d). What would be the correct amperage for the fuse to just the blower motor?

Sorry, seemed like someone looking at this thread might have the quick answer.

Thanks

Sorry again, I got nothin' on that blower motor issue...

[my123ca]

Originally Posted by Zacharias

Two questions:

1. What is the issue with the original blower motor that was slowing down after a few minutes? Brushes worn?



Thanks

Could be a worn out commutator.

[Zacharias]

Originally Posted by Diesel911

Was the replacement a new motor or a used motor?

If it was a used motor either the bearings need to be replaced or lubricated.

Also some have Bosch Motors but mine has a Siemans (Seimans?) Motor in it.

Sorry, should have been more clear. Used motor.

The style of motor in my car has a casing that doesn't suggest it was meant to be opened. Any suggestions on how to lube the bearing?

I do not remember if the motor actually had a brand name on it.

I can post a pic if needed.

[Diesel911]

Need more info. The Bosch Motor has the brushes in the rear and there is I think 2 threads on how to get into them and change the Brushes.

DIY Links by Parts Category - PeachParts Mercedes ShopForum

If you have a seimens motor the Brushes are up front and you need to remove the Blower Cage to get at them.

Also when I took mine apart it had a lot of dirt and dead bugs inside rubbing against the motor innards.

[Diesel911]

Originally Posted by koooop

Thread hijack here! PO hooked the blower motor up in my '81 240D to the sunroof circuit (fuse d). What would be the correct amperage for the fuse to just the blower motor?

Sorry, seemed like someone looking at this thread might have the quick answer.

Thanks

Sorry again, I got nothin' on that blower motor issue...

If it is still there you have a Fuse chart in the lid of the Fuse Box. It sohould tell you what amperage the Blower Fuse is.

[koooop]

Originally Posted by Diesel911

If it is still there you have a Fuse chart in the lid of the Fuse Box. It sohould tell you what amperage the Blower Fuse is.

Unfortunately the fuse box lid I have does not match the fuse box. The chart on the lid does not even show fuse d ( for the nonexistent sunroof ) however my fuse box does have a fuse d and that's what's currently running my blower motor.