3.5L Alternators

[pajpwr]

For anyone that has a 3.5L Pajero and does anything involving mud!

The 3.0 Paj engine has the alternator mounted as high as possible. Unfortunately, the 3.5 has it mounted significantly lower, low enough to be filled with crud when mud plugging (you can spare me the "evils of mud" lecture :-)

Having gone through three alternators I've figured out how to make them live longer:

1. Get some rubber (see your local Clark Rubber) and extend the flexible guards that stop crud flying front the front wheelwells into the engine compartment, on both sides. On mine I could look directly into the alternator's internals from the driver's side.

2. Close off the front. No crud should be able to enter the engine bay, for example the gap between the top of the front bashplate and your bull/bumper bar. I added a chequerplate guard for this which is effective.

3. Check your internal plastic guard. This is hard to describe, but if you take off the front bashplate you should see a bit of flat plastic hanging vertically. My '96 NJ didn't have one, and so the way was clear for crud to enter the engine bay. A new one cost $40 from Mitsu. There is also a hole in the guard for some reason; no longer, thanks to Araldite and Clark Rubber.

With these mods my current alternator has survived a fair amount of offroading, so I hope they will be of some use to other 3.5 owners.

Cheers

[Bitsamissin]

Rob, yes thats a very good mod especially for us slush monkeys down here. It does amaze me why manufacturers mount critical items like that then show commercials of their vehicles barrelling through massive sludge pits.
If you want to read an interesting story about this very issue try this:-
http://www.offroad.au.com/homepagetext0109.cfm
I've gone through a starter motor, 2 idler pulleys, clutch fan assembly and the a/c pump main bearing is rooted and I don't want to talk about brake pad wear (yes the Bendix 4x4 ones). But because the alternator is mounted as high as possible it's survived. If they only fitted sealed bearings it would save a lot of drama's.
When you runnin the Mt Dissappointment trip ? I gotta try that hill.........
Just don't make it Jan 19th (Gembrook trip) or Feb 1st (very drunk).


Frank.

[RUFF]

This is the same prob that 22R petrol Hiluxs have. The alternator is way down low on the left side and fully exposed to the eliments in mud.
When i first started wheeling the current Lux i was compeating in a few Mud Runs and after every event i would have to replace the alternator and also the AC idler bearing. With a hilux you cant realy do much to stop the crap getting in there. But i ended up converting to a VN 5ltr 85Amp Bosch Alternator and have never had a prob since.
I may be wrong but do the Pajero's run an internal fan alternator?
If so i think this is the major cause. It gets the muddy water inside and then the fan throws it out into the windings and then into the bearings where as the bosch external fan tends to push the water away more not suck it in.

[DFullMonty]

Here in The States, we have the same problem, on the 3.0 engines, they moved the alt down to the bottom of the engine in 92, or 94 I think, in any case, it is in the WRONG place for mud!
Has anyone tried to remount the power steering pump down low and move the alt up to where it should be? I can't decide which would be better, that or the cover up mentioned earlier...
I think I will try to seal that area up better, cause I know that's what did my last alternator in, too.
By the way, nice board, and I am glad to see more Pajero/Montero drivers getting out there.

[DougH]

Here in The States, we have the same problem, on the 3.0 engines, they moved the alt down to the bottom of the engine in 92, or 94

It was moved on the dohc engines. The sohc engines do not have the low mount altenator. The heads are probally completely different castings, so I doubt you could attatch the sohc mount to your head.

Otherwise, get all your brackets from a 3.0 up to 93, and you might be able to work it out.

The block is the same, so the power steering pump might be workable. Dont know what other brackets you would have to replace though.

[Bitsamissin]

Thats a good one Ruff, will definitely look into that if mine goes AWOL.

[pajpwr]

I don't see why a shield couldn't be fabricated for alternators and starter motors. I know they need air cooling, but a properly designed shield could actually improve airflow as well as shield. After all, the crud will come up from the bottom, and the air can be guided in over the top.

As for Mt Diss; as soon as whatever is wrong with my tranny is fixed!

Cheers

[pajpwr]

OK, here are some pix:

The guard I was talking about, that many Pajeros have but for some reason mine did not:




The alternator. Yes, the radiator is out. I have heard it is possible to remove the alternator without the radiator, but it's beyond me.

[Bitsamissin]

Thats very interesting Rob, at least they made some sort of effort to protect the lower mounted alternator in the 3.5 V6, they must have been aware of a potential issue ?
I've never seen it on a 3.0 V6 maybe it was on later model 3.5's ?
The crossmember above your splash shield is where Baz mounted the air tank there are 2x 8mm threaded holes (350mm centres) and are used for mounting the tranny cooler in the auto's so in a 5sp it's all empty space.
I also cut away the panel just behind the bullbar so it is all clear behind there.