Pagoda SL Group

W113 Pagoda SL Group => Electrical and Instruments => Topic started by: VincentR on August 31, 2015, 08:26:33

Title: 280sl alternator part number
Post by: VincentR on August 31, 2015, 08:26:33
Hello All,
Do you know the original part number (MB & Bosch OEM) for the Pagoda 280SL Alternator?
Thanks in advance.
Best regards.
Vincent R
280 sl 1970 France
Title: Re: 280sl alternator part number
Post by: mbzse on August 31, 2015, 10:52:07
Quote from: VincentR
.../... original part number (MB & Bosch OEM) for the Pagoda 280SL Alternator
Alternator: Bosch 0 120 400 504  K1 14V 35A  20  (also: Bosch 0 120 400 606)
/Hans in Sweden
Title: Re: 280sl alternator part number
Post by: Naj ✝︎ on August 31, 2015, 10:56:38
Hello, Vincent,

Do you know if your alternator is 35 amp or 55amp?

Earlier cars had the 35 amp alternator Bosch # 0 120 400 606. These are NLA.

The 55a alternator is available as a remanufactured unit Bosch # 0 986 031 020 (with integral regulator) and uses the 3 flat blade euro plug.
The last time I checked, the price from Bosch was around €500.00. Sometimes you can get Bosch rebuilt units from Valeo # 436121

naj
Title: Re: 280sl alternator part number
Post by: VincentR on September 04, 2015, 13:44:29
Hello Hans and Naj,

Thank you for your answers.

@ Naj : my 1970' 280SL is fitted with one regulator (new version in electronic I fitted from from Bosch ) on the front right inner wing : is it compatible with the new (integrated regulator) alternator?

Best regards.
Vincent.
Title: Re: 280sl alternator part number
Post by: Naj ✝︎ on September 04, 2015, 20:00:10
Hello, Vincent,

If you change to the alternator with the integral regulator, then the separate one becomes redundant.

The alternators are the same, the only difference being the brush plate. One has three spade terminals and uses the external regulator or the other one has an electronic regulator built into the brush plate and you only need to connect the blue wire (operates the warning light) from the loom to the separate D+ terminal on the alternator with the integral regulator.

naj
Title: Re: 280sl alternator part number
Post by: VincentR on September 09, 2015, 09:31:37
Hello Naj,
Thanks for your information.
Is the current brush plate (w/o integrated regulator) compatible with the new alternator (to enable to still be in external regulator confirguration even with the new alternator) ?
Best regards.
vincent
Title: Re: 280sl alternator part number
Post by: johnk on September 09, 2015, 16:21:57
I recently purchased a rebuilt 55 amp Bosch from FCP (FCPEURO.com) for $70 which fit perfectly. It was a Bosch AL72X and works great.
Title: Re: 280sl alternator part number
Post by: Naj ✝︎ on September 11, 2015, 21:41:06
Hello Naj,
Thanks for your information.
Is the current brush plate (w/o integrated regulator) compatible with the new alternator (to enable to still be in external regulator confirguration even with the new alternator) ?
Best regards.
vincent

Hi, Vincent,

If your alternator looks like the one in the pictures, then yes
Title: Re: 280sl alternator part number
Post by: VincentR on September 21, 2015, 13:23:16
Hello All,
Thank you for your information.
I will keep you informed.
Best regardS
VincentR
Title: Re: 280sl alternator part number
Post by: Erics on October 18, 2015, 08:12:01
Resurecting an older thread...

Will this fit a 1968 280sl?

http://www.mister-auto.co.uk/en/alternator/valeo-436121_g4_a021436121.html
Title: Re: 280sl alternator part number
Post by: Naj ✝︎ on October 18, 2015, 10:41:40
Resurecting an older thread...

Will this fit a 1968 280sl?

http://www.mister-auto.co.uk/en/alternator/valeo-436121_g4_a021436121.html

This alternator is for later model cars, W114, W123 etc.

Your car is probably fitted with a 35a alternator which Bosch no longer supply (but can be rebuilt). You can change to a 55a alternator but you will need to modify some of the wiring. The 55a alternator is MB 003 154 6202 or equivalent.

naj
Title: Re: 280sl alternator part number
Post by: Erics on October 18, 2015, 15:42:10
This alternator is for later model cars, W114, W123 etc.

Your car is probably fitted with a 35a alternator which Bosch no longer supply (but can be rebuilt). You can change to a 55a alternator but you will need to modify some of the wiring. The 55a alternator is MB 003 154 6202 or equivalent.

naj

Hi Naj and thank you very much for the kind comment.

Here are a few pictures of the potentially faulty alternator. If you could please help me to identify it.. Like this i could try and find the exact replacement part..

Title: Re: 280sl alternator part number
Post by: Erics on October 18, 2015, 17:20:39
Whilst i wait for someone to tell me what the above alternator is (35a or 55a??).

The AA guy came yesterday and helped me jump start the car with spare cables. When flat the (brand new) bosch battery gave 11v, so been clearly drained.

At idle, it gave 12.2v. I would have thought if alternator dead it would give 11v at idle too.

The fact that it gives some voltage means that it may be something else? Regulator? Any idea?
Title: Re: 280sl alternator part number
Post by: Naj ✝︎ on October 18, 2015, 18:54:53
Hi, Erics,

Yours looks like a 35a alternator.

To change to a 55a alternator with an internal regulator, you will need a 3 blade Euro plug. The 2 B+ wires go to the 2 wide blades. Use the D+ wire from the old 3 pin plug. The old regulator becomes redundant.

naj

P.S: Here is a link to an after-market 55a alternator.

Note it does not have an internal regulator. To use it, you would have to change your 3 round pin plug to a 3 flat blade plug and use your old regulator or change the brush plate to one with an internal regulator. You would still need the 3 pin Euro Plug for the B+ wires.

http://www.woodauto.com/Unit.aspx?Man=BOSCH&Ref=0120400723

naj
Title: Re: 280sl alternator part number
Post by: Erics on October 19, 2015, 22:40:08
Thanks Naj, going to specialist on Wednesday...
Title: Re: 280sl alternator part number
Post by: Erics on October 23, 2015, 13:53:29
Quick update on this. I spoke to Simon at the SL shop re what could have happened to my brand new alternator.

His opinion is that the wires going to the alternator melted due to going the 'shortest way' from the right hand side wing to the alternator.

In his opinion, this got the wires too close to the engine headers and melted the wires.

The 'right' way to do it apparently is to route the wiring loom the 'long' way which is supposedly from the top of the alterntor and keep any wiring as far as possible from heating source in the engine bay.

Apparently, it is a common mistake that restorers make. I was not aware of it and my alernator is presumably kapput as a result. :(

Better be informed then...