Leak from underneath defender 90

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That is exactly the sort of set I was referring to. I got mine when I was 18 (18 years ago) so it does not look like that and it is still in regular use and I have only broken one spanner and that was through mis-use, but as long as you don’t tel them that had no issue getting it swapped in store.
That's going some to break a spanner!
I have cut bits off spanners but never broken one.
 
So they confirmed it's the transfer box output seal which is leaking?
Corteco seals are good choice, Britpart specials are not.
Smith & Allan are pretty good for oil, bear in mind transfer box and axles use the same oil so don't bother buying 1/2 lit at Halfords (if they sell it).
Yeah he said there was a bit of play in it and he said that could be the bearing, but they don't do the bearings there so he's just going to do the seal and see if it stops. The guy we got the truck gave us a couple of seals which say corteco on them
 
Just to make you feel better again I have rebuilt mine three times (chassis replacement, rebuild after an engine fire, conversion to a station wagon with the last two well documented on here), and mine still leaks. Currently from the steering box!

I bought my 110 at 18 and as a student (best use of a student loan ever) so I had a very steep learning curve as I couldn’t afford to put it on a garage. If you want to learn the basics these are the perfect vehicle to do it on and the forum is full of friendly and helpful people. Do not be afraid to ask silly questions (like what/where the diff is) someone will always answer.

I would start as above by checking the gearbox (fill plug on the side) the transfer box ( fill plug pictured above) and the diff (fill plug pictured above) oil levels. As mentioned all are full to level which means you put oil in until it leaks out the fill hole. This will also give you a little bit of confidence that working on the vehicle may be dirty and heavy but is not difficult.

In terms of the tools to do the job:
1/2” open ended spanner (can use a 13mm at a push if careful not to round the square plug)
1/2” drive ratchet
Maybe 1/2” drive extension bar


Oil required to top up (a can of worms people like to argue about)

Diffs: ep90 gear oil
Transfer case: ep90 gear oil
Gearbox: ATF


If you are just starting out and don’t have any tools the large Halford advanced 200ish piece box set is a good starting point as it comes with a life time warranty. Everything else my advice would be to buy as you need it for a job and build up tools that way.
Thankyou that's a really detailed explanation and so helpful!! 😊 We are enjoying learning all this and wanting to get to know what we are doing and this forum makes it possible.
 
You obviously need a longer scaffolding pole :)
Funny that was exactly what did it! The open end on the bolt with a large pipe on thw other to break mine. Think it was a 13mm was something small enough I was expecting the bolt to snap, but couldn’t access with a socket to deliberately shear the bolt!
 
Funny that was exactly what did it! The open end on the bolt with a large pipe on thw other to break mine. Think it was a 13mm was something small enough I was expecting the bolt to snap, but couldn’t access with a socket to deliberately shear the bolt!
It usually is.....or so I'm told :)
 
@tottot is bang on, the seal is leaking quite badly and the warm oil is washing back along the case and dripping when standing (or marking its territory) be worried when it stops dripping, that means it’s empty. This pic circles the seal location (yellow ring) and direction of flow (blue arrow).
You need to find a local independent garage to get it sorted pronto! - where are you in the UK? Folk on here will surely recommend a friendly….
 

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@tottot is bang on, the seal is leaking quite badly and the warm oil is washing back along the case and dripping when standing (or marking its territory) be worried when it stops dripping, that means it’s empty. This pic circles the seal location (yellow ring) and direction of flow (blue arrow).
You need to find a local independent garage to get it sorted pronto! - where are you in the UK? Folk on here will surely recommend a friendly….
Thankyou 😊

It is booked in next week on Wednesday for the seal. Weirdly the ex owner is adamant its not the seal and blaming overfilling (see photo attached). Yet it's leaving fairly big puddles everything we park it up

We are from Norfolk, near Thetford. If anybody is local we'd love a meet up to show us some basics 😅
 

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Thankyou 😊

It is booked in next week on Wednesday for the seal. Weirdly the ex owner is adamant its not the seal and blaming overfilling (see photo attached). Yet it's leaving fairly big puddles everything we park it up

We are from Norfolk, near Thetford. If anybody is local we'd love a meet up to show us some basics 😅

Personanlly I would forget what the PO says (as I said earlier sounds like some fibbing)
But you could ask him what oil he used "as you want to check level and topup if needed"

I suppose it could be a blocked breather on the transfer box.
If you dont intend to send it back and want to keep it then forget everything the PO is saying.
If its booked in for the seal then get them to check and or replace all other oils, you then know you are using the right oils in the right place ;).

Theres a few guys in that area that could help point out basics I am sure.
Have you brought some Halford spanners yet;).

J
 
Thankyou 😊

It is booked in next week on Wednesday for the seal. Weirdly the ex owner is adamant its not the seal and blaming overfilling (see photo attached). Yet it's leaving fairly big puddles everything we park it up

We are from Norfolk, near Thetford. If anybody is local we'd love a meet up to show us some basics 😅
Transfer box doesn't have ATF in it, well it shouldn't.
You could use a white tissue to see what colour is coming out of the leak on the output seal.
 
Transfer box doesn't have ATF in it, well it shouldn't.
You could use a white tissue to see what colour is coming out of the leak on the output seal.
So if he 'overfilled with ATF' which should be for the gearbox (I am learning lol), is the gearbox near the transfer box to have spilt on it?
I will check the colour with tissue after work
 
Personanlly I would forget what the PO says (as I said earlier sounds like some fibbing)
But you could ask him what oil he used "as you want to check level and topup if needed"

I suppose it could be a blocked breather on the transfer box.
If you dont intend to send it back and want to keep it then forget everything the PO is saying.
If its booked in for the seal then get them to check and or replace all other oils, you then know you are using the right oils in the right place ;).

Theres a few guys in that area that could help point out basics I am sure.
Have you brought some Halford spanners yet;).

J
Yeah we had decided to just forget what he's saying now as we have no idea what's even true. We haven't been off work yet to get spanners but we definitely will start acquiring the right tools 😀

We haven't looked under the drivers seat plate yet is that a way you can top some fluids up?
 
So if he 'overfilled with ATF' which should be for the gearbox (I am learning lol), is the gearbox near the transfer box to have spilt on it?
I will check the colour with tissue after work
In your pics frome earlier.
Your main "black oily" bit is the transferbox.
The dry dirty light brown is the gearbox, the drain plug for it is the big bolt head in 1 of your pics. the fill/level plug is up and forward of that.

Your garage will soon tell you if its ATF/MTF when they do the seal, maybe the owner will tell you if you ask him the question I mentioned earlier.

J
 
So if he 'overfilled with ATF' which should be for the gearbox (I am learning lol), is the gearbox near the transfer box to have spilt on it?
I will check the colour with tissue after work
The transfer box is a separate unit bolted on the back of the gearbox, the front and rear propshafts are bolted on to the transfer box. They both use a different oil, the main gearbox should be a thin red oil, the transfer box should be a light golden brown colour and is a thick oil which smells.
(Other colours are available)
 

This channel has useful videos to watch.

So does this one, although I have just picked random video as I don't know how to link a channel. Just choose some videos for info when a problem appears or for general knowledge.
 
The transfer box is a separate unit bolted on the back of the gearbox, the front and rear propshafts are bolted on to the transfer box. They both use a different oil, the main gearbox should be a thin red oil, the transfer box should be a light golden brown colour and is a thick oil which smells.
(Other colours are available)
This is what I just wiped from where it looks like the leak is, I'd say more light browny slightly orange. So looks like it's from transfer box rather than atf what he said?
 

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