120 amp alternator

[gsr341]

hello again

ive recently purchased a 120 amp alternator , suposedly off a 300tdi discovery , to go on my 300tdi defender , it fits on the brackets fine (after i drilled the threads out of the bottom mounting bracket )

my original pully will not fit on the new shaft , diameter is correct , just the disco unit has a slight recess on the front cover , so the defender one would rub the alternator housing

is a simple job of just needing the disco pully ?

and if so does any one know the part number please

thabnks for any help

dafydd

[western]

and if so does any one know the part number please

EPC tells me there's 2 types of pulley

STC3691 Pulley alternator [2500 cc - 4 Cylinder - Diesel - TDi]

or

STC1796 61mm [diameter I think]

& in the Defender section

STC3202 49mm for Defender 300Tdi also list the 61mm version part number as above

Edited April 25, 2006 by western

[gsr341]

cheers Westen

any idea which one i would require ?

[western]

cheers Western

any idea which one i would require ?

Defender 61mm pulley for VIN To (V) MA 969102

& 49mm pulley for VIN From (V) TA 969103

Not sure which one you need SORRY

[BogMonster]

300Tdi Discovery alternators are 100A not 120A, so maybe if it is a 120 it is not a standard Tdi alternator? The only 120A ones I can think of are Td5 ones which I *think* are 120 but they are a different thing altogether.

As long as you don't have a rev counter it doesn't matter what size pulley you have on there - you just need the right length belt, all belts are the same width (7PK I think i.e. 7 grooves).

If it is a big pulley it is an early one requiring belt ERR3287 if it is a small pulley it is a later belt ERR5911. If you want the non squeak belts the early one is PQS000030 and the later one is PQS000040. The only differences are that the small pulley makes the alt work better at idle revs, and it screws up the rev counter if you have the wrong one fitted. No rev counter, no problem.

[minivin]

were the 120A possibly fitted to the Air Con TD5's per chance? or maybe even the ABS and traction control varients, just that I know a few vehicles such as my motorbike, that when they fit something like ABS they upgrade the alternator to cope with the higher power loading

[geoffbeaumont]

No rev counter, no problem.

Unless you have air suspension (probably not relevent in this case... ) - the EAS ECU also uses the tach wave from the alternator to determine whether the engine is running over a minimum RPM. If it isn't, it won't play... Pulley size is unlikely to be a major factor, but the type of tach output is - the ECU, like the rev counter, will only work with the older wave type, not a modern pulse tach. That's the original range rover classic type EAS - no idea about later versions.

As the saying goes...ask me how I know

[Ivan]

Sorry to hijack this thread but, I have a 300 Tdi fitted into my 90 (1986 was Turbo Diesel). I have replaced the bearing in the tensioner but the bloody thing still squeaks. Could it be the belt ?

Cheers

Ivan

[BogMonster]

it usually is the belt, collects dust with the efficiency of a Dyson Root Cyclone

mine is always squealing but a quick puff from a small bottle of graphite dust onto the belt with the engine running sorts that out

[Ivan]

Cheers Steve. I'll give it a go.

Rgds

Ivan

[gsr341]

heres some pics of the alternator deffently says 120amp @14volt ?

does any one know what pully i will need for her ?

[BogMonster]

if it is an A127-120 I am pretty sure it is not a standard Discovery Tdi fitment so you may not even get a pulley to fit, if you do I think you just have to go with the trial and error method!

[simonr]

Your new alternator is internally cooled - so you don't need the turbine thing on your original alternator.

You should be able to make it work using spacers to move the pulley away from the front bearing. Most alternators have one or two of the things - but they can easily be improvised (M16 washers usually work).

It is (usually) as simple as that.

Si