Assuming the squeals from the AC/air/heater vents is coming from the air-blower bearings... Has anyone had long-term success with re-lubricating an air-blower in a W124? Late last Winter and early Spring it was intermittent, and could be "cured" by switching to high or low. Now, the blower's squeaks and squeals have gotten more consistent - noisy all the time - on all 3 settings. So I just turn up the radio's volume, and enjoy the cool AC.

Anyway, this is a used replacement blower from an 87 300D. I wonder if it can be re-lubed and revived, or if efforts to re-lube are just be a short term fix. I re-lubed one in a previous 124, but sold it soon after and I don't remember if it squeaked in the first place. And I think I remember the bearings were not accessible, just oil down the shaft, and it did not spin any faster or longer. Is there a way to re-lube the bearings with a light grease?

Since I plan to keep the car, I'd prefer the real repair, not just a short-term fix. Something that lasts 3 yrs or 75k.

Any comments on the 3 choices? New blower$$, used blower from a later W124, re-lube mine. Thanks

John
87 300TD 310k

It's going to stop working on you. I have no experience lubing the bearings BUT the blower is hard to get to. You will likely need to lube it a few times over the winter. Best to start looking for a new one. They are cheaper without the squirrel cage, but the cage is difficult to remove in one piece. Buy a Bosch with the cages and never worry about it again.

__________________
08 R320 CDI current

Past
95 E420
87 300D Turbo 5spd
90 300TE
83 300SD
85 300TD
92 400E
85 190D

Yeah, buying new - full blower - might be the best way, but most expensive. I'm holding out hope for a cure - the mythical one-shot re-lube strategy with no parts cost, only time. Do I hear an Amen?!?

It is worth a try.

__________________
Jim

That's the Problem!

It's got "Bushings"

If it had Bearings (Preferably 2RS ,Rubber Sealed on both sides) You'd never have the problem in the First Place.

All Victimized by Mercedes instructing Bosch to produce a "Guaranteed to Fail"
part (A Hat Trick for MB:They save money on the Original Part,They make
money selling you the new part,They make a fortune in Labor R+R ing the Parts.)

The Motors in Chassis that have Air Filters seem to last longer
(Less Dirt + Trash exposure to the Shaft Bushings)
But the Motors are of the same Inexpensive design [Air Flow Cools Motor]
IF the Motors were Re-Designed [No Hope]
OR could be Rewound (for more power)and Sealed (even if you had to had to
use a Heat Sink) ,Along with Bearing-ization.

Attached Thumbnails

 

__________________
'84 300SD sold
124.128

bite the bullet do the replacement. It's straightforward and it'll fix your problem

__________________
hum.....
1987 300TD 311,000M Stolen. Presumed destroyed

I found some industrial motors online that where practically the same size and 12 volt. They had bearings and looked much better made. But since a new one will last over ten years, it's not worth messing with it.

__________________
08 R320 CDI current

Past
95 E420
87 300D Turbo 5spd
90 300TE
83 300SD
85 300TD
92 400E
85 190D

Stone sober fact... I wish my turbo's bushings had given me a squeal of warning... so the best performing solution is buy another of those brand new guaranteed to fail beauties.

So the next big question is...Is there a blower that has a more variable set of speeds? and fits-up?

I don't recall the google search parameters I did. But I was close to doing it. I think they were in the $60 range.

I dont think it would be too hard to put sealed bearings on an existing blower motor.

But your brushes are likely in bad shape too.

__________________
08 R320 CDI current

Past
95 E420
87 300D Turbo 5spd
90 300TE
83 300SD
85 300TD
92 400E
85 190D

Blower speed and the number of increments between min and max is determined by the CCU, not the motor.

Sixto
87 300D

Sixto,
In both of my 124 TD wagons the fan blower has 3 buttons. Low, High and the mid button is variable to moderate the cabin temp. The Low and high always seems to blow at their same speeds. You're saying that speed is governed by the CCU. So that means the CCU would have to be changed out too, not just the blower and buttons. Or is it possible to get more buttons or a dial?

(Controller) "Resistor/Regulator"

This (Picture Below) is what the C.C.U. uses to "Control" the Blower Speeds.

ANY Electric Motor within the D.C. and Amperage Limitations of the O.E. Motor
will respond to the (Un-NECESSARILY COMPLEX) Dua-listic Motor Control System.

The "Secundo" Assault on your HVAC Air movement is:

If the Controller/Resistor/Regulator overheats, It's Toast and will take out the
Blower Mayhaps.

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__________________
'84 300SD sold
124.128

Feels like I'm off on a path to nowhere cheap and easy. And the solution to the least long-term pain is a new Bo$ch blower motor. Thanks for your help.

The CCU sends a voltage signal to the blower controller (procupine) which provides power to the blower motor. The CCU sends either a low signal (MIN), high signal (MAX) or an intermediate signal (AUTO) based on selected mode and temperature conditions. Are you saying that you put the CCU on AUTO but the blower speed doesn't respond when you vary the temp wheel? If so, that could be a faulty CCU but it could also be a faulty cabin temp sensor.

There are options for manual blower speed control. You can set the blower to MAX and use a rheostat to modify the signal to the blower controller. You can also get creative with a Euro non-ACC control set. That's a lot of work either way. You can replace the airbox with a Euro non-ACC airbox that uses Bowden cables instead of vacuum pods, or replace the mode selector dial with an electrical switch to operate the ACC solenoid bank. You'll still need a solution for temperature control.



Sixto
87 300D