Alternator swap

OK my 93 Spanish spec 200 tdi Alt is charging well but the dash light is on, but as dual batteries are being fitted this week I ordered a new 100 amp Alt.

The old alt is a Magnetti Marelli A127 - 65 amp V pulley, the new model is Magnetti Marelli A127 1M - 100amp, internal fan, the problem is that although the alt looks like it will fit the pulley on the new one is for a multirib belt presumably 300 tdi, I spent nearly an hour trying to undo the pulley on the old alt with no luck, before I get out the adjustable spanner (read big hammer) after all this work will the old V pulley swap over?

Also can someone run outside and check their 300 tdi and see if there is a plastic shield over the wires?

Thanks in advance

Dave

Dave 2000 said:

OK my 93 Spanish spec 200 tdi Alt is charging well but the dash light is on, but as dual batteries are being fitted this week I ordered a new 100 amp Alt.

The old alt is a Magnetti Marelli A127 - 65 amp V pulley, the new model is Magnetti Marelli A127 1M - 100amp, internal fan, the problem is that although the alt looks like it will fit the pulley on the new one is for a multirib belt presumably 300 tdi, I spent nearly an hour trying to undo the pulley on the old alt with no luck, before I get out the adjustable spanner (read big hammer) after all this work will the old V pulley swap over?

Also can someone run outside and check their 300 tdi and see if there is a plastic shield over the wires?

Thanks in advance

Dave

Click to expand...

Mine has the small plastic shield on the back of the alternator, 3 wires underneath (97 R 300TDi)

Many thanks for that, the new one does not have that. My concern is that the old alternator draws cooling air from the back of the alternator, there is a plastic cover that prevents hot air been drawn from the exhaust and turbo, the new alternator has an internal fan so I assume it pulls in from the front and blows out the sides and back.

The cover you mention I assume (and hope) is just to prevent shorts from the terminals.

Thanks again

Dave

As long as the keyway on the shaft is the same, it should swap over. Best way I've found to remove pulleys is to wrap an old belt around them and clamp that in a vice as tight as possible. Should be able to get the nut off then if you use a good socket and a long bar.

OK, I will soon know tommorow, thanks for the tip about the old belt.

regards

Dave

Go Dave Go Dave Go Dave..............yep it all fits and works, the rub on fitting the 300 tdi alt (A127 1M) to a 200 tdi is that:

1. The pulley will swap but you need to space carefully to get the pulley central.

2. Although the mount at the top that the alt hangs/swings from is perfect the adjustment bar is out of line with the power steering bracket so a small spacer of 3/8" is needed.

3. The wiring is as the same as the old alt except cut off the suppressor and binit, then cut off the ring connector and fit a spade terminal.

All done 100amps lovely job, took me longer to get pulley off than it did to fit. Please bear in mind my 200 tdi is Spanish spec LHD ect.

Hope this helps anybody thinking of upgrading.

regards

Dave