300SDL alternator bearing sizes? - Page 2 - PeachParts Mercedes-Benz Forum

torsionbar · #16 03-09-2018, 10:05 AM

Quote:

Originally Posted by Father Of Giants

What mods are necessary? How do I do them?

1. clk430 alternator has a fixed pulley with incorrect offset for om diesel engines. replace the pulley with the correct diesel engine clutched pulley.
2. reindex the alternator so the cables line up properly. remove the four perimeter case screws, rotate rear half 90 degrees in relation to the front case half, and bolt it back together.

note that an early clk430 alternator is required i.e. up to and including year 2000. the 2001+ ones have incompatible wiring connections.

of course if you intend to do this, it would be silly to not also replace the rear bearing, tolerance ring, and voltage regulator while you have it apart on the bench.

Father Of Giants · #17 03-09-2018, 10:28 AM

Quote:

Originally Posted by torsionbar

1. clk430 alternator has a fixed pulley with incorrect offset for om diesel engines. replace the pulley with the correct diesel engine clutched pulley.
2. reindex the alternator so the cables line up properly. remove the four perimeter case screws, rotate rear half 90 degrees in relation to the front case half, and bolt it back together.

note that an early clk430 alternator is required i.e. up to and including year 2000. the 2001+ ones have incompatible wiring connections.

of course if you intend to do this, it would be silly to not also replace the rear bearing, tolerance ring, and voltage regulator while you have it apart on the bench.

Where can I find a tolerance ring?

tjts1 · #18 03-09-2018, 10:32 AM

Quote:

Originally Posted by torsionbar

1. clk430 alternator has a fixed pulley with incorrect offset for om diesel engines. replace the pulley with the correct diesel engine clutched pulley.
2. reindex the alternator so the cables line up properly. remove the four perimeter case screws, rotate rear half 90 degrees in relation to the front case half, and bolt it back together.

note that an early clk430 alternator is required i.e. up to and including year 2000. the 2001+ ones have incompatible wiring connections.

of course if you intend to do this, it would be silly to not also replace the rear bearing, tolerance ring, and voltage regulator while you have it apart on the bench.

No, that's not necessary. He'll have to run a different cable from the battery to the alternator and can position that to accommodate the alternator. The pair of 30awg wires for the B+ terminal in the 86/87 can only accommodate about 60a.

Father Of Giants · #19 03-09-2018, 10:43 AM

Quote:

Originally Posted by tjts1

No, that's not necessary. He'll have to run a different cable from the battery to the alternator and can position that to accommodate the alternator. The pair of 30awg wires for the B+ terminal in the 86/87 can only accommodate about 60a.

So I need thicker wire?

tjts1 · #20 03-09-2018, 11:18 AM

Quote:

Originally Posted by Father Of Giants

So I need thicker wire?

The existing pair of 30awg wires running to the back of your alternator are a common failure point even without upgrading the alternator. The terminal is the weak points.

Teminal 1 and 2 are replaced by A. Terminal 3 is replaced by B.

Your car might have already been converted to the newer terminals already.

torsionbar · #21 03-09-2018, 11:37 AM

Quote:

Originally Posted by tjts1

No, that's not necessary. He'll have to run a different cable from the battery to the alternator and can position that to accommodate the alternator. The pair of 30awg wires for the B+ terminal in the 86/87 can only accommodate about 60a.

The instructions I provided were in reference to his inquiry on my installation of a CLK430 alternator into my w210. I cannot speak to the requirements of his 86 SDL, that's a different animal.

torsionbar · #22 03-09-2018, 11:40 AM

Quote:

Originally Posted by Father Of Giants

Where can I find a tolerance ring?

I normally buy from the internet. There are many vendors to choose from. See my earlier post for the part number.

tjts1 · #23 03-09-2018, 11:45 AM

Quote:

Originally Posted by torsionbar

The instructions I provided were in reference to his inquiry on my installation of a CLK430 alternator into my w210. I cannot speak to the requirements of his 86 SDL, that's a different animal.

It's the same.

jay_bob · #24 03-09-2018, 04:00 PM

I did this to my 87 300TD (OM603 powered). I went to the JY and found an alternator out of a circa 1990 300E (M103 powered).

The gas cars had a bigger alternator than the diesels, so they had bigger wires. This meant they could not use the horrid plug in connector that they used on the early OM603s. Instead there is a ring tongue connection on the alternator for both the B+ (main output, fat wires) and the D+ (excitation/indicator light circuit, skinny wire).

I got the alternator, and removed the wiring harness complete to the terminal block near the battery. I also got the terminal block.

It passed the spin test in the junk yard. I pulled the VR and confirmed it had good brushes and the commutator was in good condition. So I rolled the dice and paid my $20 or so.

Took it to the AutoZone and had it tested and it passed fine.

The cable is a slight pain to remove, it’s threaded through some grommets between the battery and the alternator.

The gas alternator bolts in directly to the same mount points on the OM603 block.
Pro tip: use a wire brush and brake clean on the mounting ears on the alternator and the engine block, gently make them clean and shiny, this is how the alternator is grounded. If this connection is dirty, it will prevent the alternator from reaching its full output.

The wiring harness threads back in the same way and the terminal block fits in the same holes in the fender well.

Around here there are a good number of gas 124s and 126s showing up in the yards. Many are there for a terminal engine or transmission problem, so the alternators are often in working condition.

vstech · #25 03-09-2018, 08:15 PM

FYI, most 90s Chevrolet’s, Saab’s, bmw’s, and nearly all MB’s use the same alternator mount.

If you don’t want to build a wiring harness, any gasser Mercedes OTHER THAN THE E420and up... they route stuff to the rear of the vehicle... no help on your car... alternator harness will fit.
190,124,126, etc...

Father Of Giants · #26 03-11-2018, 02:53 PM

I got the alternator, and some wiring but couldn't get the alternator wire on the starter solenoid.
Should I just go make my own wire or should I pull a alternator wire off of a local ML320?

tjts1 · #27 03-11-2018, 03:55 PM

Quote:

Originally Posted by Father Of Giants

I got the alternator, and some wiring but couldn't get the alternator wire on the starter solenoid.
Should I just go make my own wire or should I pull a alternator wire off of a local ML320?

The thick wire runs from the alternator to the battery, not the starter.

Father Of Giants · #28 03-11-2018, 03:57 PM

Quote:

Originally Posted by tjts1

The thick wire runs from the alternator to the battery, not the starter.

Wow, I'm dumb, I'll go back tomorrow.

Father Of Giants · #29 03-11-2018, 09:53 PM

Also is there a way to remove the wiring without cutting it?
Learned a lesson today, when going to the junkyard, bring everything.

Father Of Giants · #30 03-12-2018, 01:40 PM

Got the alterntors, problem is what do I do with the small wires?

The Bosch alternator has one small wire, the Valeo has two small wires. Do they matter?