alternator dumping oil out of pump

[Hawky]

My alternator has decided to dump oil out of the pump , i removed the alternator to check it out and i found that the clamps on the hoses were a little loose contributing to some oil loss . I also found broken fibre washers on one of the banjo bolt fittings , my question is , is it a standed thing to have six washers on one banjo fitting , a copper one each side and a thinnish fibre washer each side of copper washer . I would have thought a fibre or copper washer each side would be sufficient. The alternator is charging fine but is their anything else i should replace on the pump while i have it out of the vehicle. I have included a pic of said washers and alternator.

[threedogs]

My take on it would be copper washers are a single use service item, once squashed throw away and use another,
unless you were half way across the Simmo with no new ones.

[Hawky]

threedogs i will be fitting new ones but is their any reason for having the six washers rather than just two .

[Yendor]

Are you sure that's only where the oil was leaking from?

There is an oil seal between the oil pump housing and alternator housing that may also be leaking. Normally when this seal leaks oil go through the alternator.

[BigRAWesty]

Yes one a side is plenty. But while you have the vac pump off replace the 2 internal o rings.

Kallen Westbrook
Owner of
Westy's Accessories (http://www.nissanpatrol.com.au/forums/showthread.php?15134-Westy-s-Accessories.-A-small-back-yard-builder.)

[Cuppa]

Someone has fixed the leaking copper washers by adding the fibre washers, rather than replacing the copper washers as they should have done. Copper washers can be successfully re-used if they are not distorted or gouged, but they need to be re-softened by heating them first to a cherry red colour and then immediately quenching them in water. In your case it would be wise to get new copper washers.

Cuppa

[Hawky]

Kallen any idea what size the o rings are , be cheaper to buy locally than from nissan dealer i'm betting.

[Hawky]

Are you sure that's only where the oil was leaking from?

There is an oil seal between the oil pump housing and alternator housing that may also be leaking. Normally when this seal leaks oil go through the alternator.

You may be right yendor as it dumped a fair bit of oil the other morning in a short time didn't realize oil would go through the alternator.

[BigRAWesty]

Kallen any idea what size the o rings are , be cheaper to buy locally than from nissan dealer i'm betting.

Sorry mate, took it to work and grabbed a couple from the kit..
But if you pop them out anywhere like repco or bursons shops be able to do them individually..


You may be right yendor as it dumped a fair bit of oil the other morning in a short time didn't realize oil would go through the alternator.

The oil doesn't actually go into the alternator. Its what provides the seal for the vacuum to work.. the impeller draws oil from sump, but because oil is heavier than air it tries to draw the lightest thing, being air and creating a vacuum in the system.. once the vacuum reaches the same weight as the oil, it just pulls more oil..

That's also why the smallest leak in a vacuum system will have such a dramatic impact.

Kallen Westbrook
Owner of
Westy's Accessories (http://www.nissanpatrol.com.au/forums/showthread.php?15134-Westy-s-Accessories.-A-small-back-yard-builder.)

[Yendor]

You may be right yendor as it dumped a fair bit of oil the other morning in a short time didn't realize oil would go through the alternator.

It's an oil seal and it's mounted in the rear housing of the alternator and it will pass oil through the alternator if it's leaking.

The o-rings don't normally leak unless the bolts are loose or you dismantle the alternator and don't replace them.

You can normally purchase the seal from any bearing shop.

Take the rear housing and rotor in with you and they should be able to measure it up and tell you what seal you need.

[threedogs]

Would think the reason for all the washers maybe that was all that was available when repaired by previous owner, "O" rings come in very handy grab kits.
Once you service clean and replace any seals and "O" rings I'm sure you'll have many miles of trouble free motoring.

Try and de grease as best you can too.
The bolt for Banjo would bottom out allowing it to leak,bring in more washers to fill the gap and so on and so on

[Hawky]

Guy's i have pulled the pump apart and the big o ring is as flat as a pancake , and looks to be falling apart . I presume the other o ring mentioned is around the shaft . I think i can see it , my next question is does this o ring require the alternator casing to be split to replace, or do you just pick it out and slip another over the end of the shaft.

[Yendor]

Yes, If the inner seal is leaking you will have oil inside the alternator so you will need to pull it apart and clean it.