Gearbox oil leak....

[revnit]

Hey guys
Ive run into a problem over the weekend i decided to top up my gearbox oil im runnign a mk1 gti 5 speed cause it does leak a bit topped it up with around 1.5litres after filling i noticed gearbox oil dripping out of the bell housing i didnt take notice off it thought i spilt some anyways next morning i went to work and notced a far bit of oil on the ground its was deffently gearbox oil i thought i may have overfilled it a bit didnt take notice drove to work fine again more oil on the ground as i lefte alot more than normal on the way home my clutch began to slip badly seems the oil has got onto it and soaked it its drivable but any power its slip now im wondering what can leak in the bell housing area??? im fairlly new to golfs can it be the imput shaft seal??? i know the clutch leaver runs a pushrod though the gearbox?? any ideas would be great im alittle stumped at the moment

[Bora Sport]

You've got it in one. The oil runs along the push rod that activates the clutch past a brass bush and a rubber seal and then gets onto the clutch plate. I hate to tell you but I am 99% sure that you will be up for a new clutch.

When you replace it make sure you replace the brass bush and the I always used to put 2 of the seals in whenever I put a new clutch in.

[gldgti]

never mind the clutch, if oil is leaking through your clutch pushrod then you have a very leaky seal in your gearbox which needs attention.

also note that the oil capacity of the 5 speed gearbox is 2L. if you topped it up with 1.5L, then you actually filled it and have been driving around with very little oil in your gearbox for a while by the sounds of it.

im not so sure your clutch will be buggered, once the oil source is gone, it should eventually wear back in ok as the oil is evaporated or burned out of it.

[syncro]

The clutch is probably stuffed. You only need to change the clutch plate if you clean everything elase up.

Make sure you fix the leak. You can't overfill it as the level is the fill up hole on the side of the box.

[aprr32]

Pull the gearbox and see if the diff has ground a hole in the bell housing, it happens more than you would think.

[h100vw]

It could be coincidence that it started to leak after the top up. It might be there was a hole in there that is now letting oil through which is why it needed so much for a top up.

There are 2 seals in there, one round the main shaft and an O ring around the push rod. I don't feel vast quantities like you describe would get through the O ring. It would certainly get past the main shaft seal if that were displaced.

I had a crank seal go on me after I changed a clutch and the garage dude just burnt the oil off the clutch plate with a torch. No issues at all in the 2 years after that.

A good soaking in brake cleaner would get 99% off I reckon if the plate isn't that badly worn.

Gavin

[Golf Loon]

Yeah the gearboxes drive a surprisingly long way with a hole in the diff.
Feel around the back of the housing for holes.

[Bora Sport]

I am talking from experience in relation to the oil getting past the pushrod seal and on to the clutch. About 20 years ago when I rebuilt my first 1.6 Golf engine I put a new clutch in as you always should with a new engine but no one told me about the pushrod seal. The original clutch was still working fine when we pulled the motor out so we didn't think there was any potential problem. 3-4 weeks after the new engine and clutch were in the car the clutch was slipping to the point where it was virtually undrivable.

Later when I got to know more Golf people they all said 'mate you always replace the seal and the bush'.

I have heard of the brake cleaner method but I haven't heard of the burning method. In my case I didn't want to have to maybe pull the gearbox out again so I put a new plate in.
Some years ago when my 16V was on the dyno the clutch was slipping and it was only a new clutch put in with the 2L engine. The guy said that there was a technique you could use to reface the plate while it is in the car. I'm not sure how he did it but it meant a controlled slipping of the clutch under load to heat it up quickly and then let it cool again. However he did it it worked because as far as I know my old 16V is still puttering around on that same clutch.

[revnit]

Thanx for the info everyone, yeah looks like ill be popping the box out shortly seems now i have a fair idea what it could be thanx for the help everyone the car is also due for a rear main oil seal so i can kill 2 birds with one stone hahaha, yeah ill probly replace the clutch anyways the clutch in it is fairly old i have spoken to my mate about the clutch he said it will proply come good over time by ridding it geting it hot then cold etc...etc... he said it willl dpend on how much oil hit it and the age of the clutch could take 3 days or 3 months.

the way it was leaking i wondered if it was a hole in the box but as was mention a hole can come about int he diff area but now thinking about it i dont think it can be cause it will hold a litre without leaking anthing over it'll drip out at a decent rate.

[h100vw]

It would depend on the height of the hole as to how much it will hold.

We had a similar problem with evorobins 16V when we built it. Got a replacement box from Golfloon and as a good egg, he fitted a new seal to the input shaft. Unfortunately the seal was for a MK3/16V box and not the earlier 8V type. The difference being the diameter of the mainshaft, they are, from memory, 22mm for the 8 and 24mm for the 16V.

As you can imagine the 24mm seal doesn't do a great job of keeping the oil in on the 22mm shaft. Hence everytime we started the engine oil started coming out of the gearbox and onto the floor. It only happened with the engine running as the oil was getting splashed around.

I wouldn't write off the hole idea until you have the box on the floor and I would do some research so you know where you can get another box at short notice if you need it.

Best of luck and fingers crossed for the cheap fix.


Later when I got to know more Golf people they all said 'mate you always replace the seal and the bush'.

From a commercial point of view, doing this would be sensible, you don't want the customer coming back later for the sake of some cheap parts, same applies to the clutch. Personally being dead tight, I would rarely stick a new clutch in, unless it was dead or I had one kicking about. Just not that big a deal to me to pull the box out if it failed down the line. Maybe a glutton for punishment but touch wood I haven't been caught yet. ;0)


Gavin