GKN Overdrive breather pipe spitting out oil

[SteveG]

As per title I noticed a trail of oil down the side of 110 today after a 70 mile journey. Not been there before, and I traced it to a wide breather pipe that goes into the top of the overdrive.

Anyone have experience of this? What's caused it to suddenly happen? Remedy?

Thanks in advance

Steve

[western]

Has yours got the white plastic canister on it ? [shown in this photo of my OD fitting] if not you need to get one as GKN modded the brether system by adding this canister to stop the oil being dumped overboard.

Edited April 2, 2007 by western

[SteveG]

Hi Ralph

Couldn't see as I was looking at it from below. When was this modification? It was fitted in September 2005.

Thanks

Steve

[JST]

mine has the old pipe system and it doen't dump oil, well not since its been run in!

Steve are you sure the vent (pipe or canister) is still attached properly?

[SteveG]

pretty sure it is, as the oil is coming out of the end of the vent pipe

The vent pipe feeds out into engine bay, up and over heater and points down between heater and wing. So it has a trail of oil down bulkhead onto outrigger side steps and down the side of the 110

Cheers

Steve

[nicam]

I had the same problem about 2 years ago.

Does the oil being blown out look or smell like pure ATF or is it contaminated with other oil? Mine was, caused by a leak on the input shaft seal to the overdrive allowing transfer box oil through into the overdrive, overfilling it and then blowing it out through the breather. Before this I noticed that the overdrive had started to be sluggish in operation - it could take 3 or 4 seconds to drop out of engagement, particularly when cold. This was due to the thicker oil.

The checks GKN told me to do were;

1) Check the breather is clear on the transfer box

2) The adapter plate has a drive sleeve with a seal - check that it isn`t damaged.

3) The seal fits around a shaft supported by bearings - check for excessive play in the bearings.

4) There are 7 bolts on the adaptor - the 2 nearest the handbrake are not sealrd and can leak oil through.

Hope that helps.

[western]

Hi Ralph

Couldn't see as I was looking at it from below. When was this modification? It was fitted in September 2005.

Thanks

Steve

my OD manual doesn't say when the expansion canister was fitted, GKN told me my OD was a 2002 build.

[Dr Goon]

Has anyone got an e-mail address for GKN that is known to work.

Mine started playing up last night so I sent an e-mail this morning to the address that appears at the botton of the spec sheet on the Devon 4x4 website. It bounced. The address was s.goodall@gkndriveline.co.uk.

Any suggestions from anyone on here as to what could be causing the overdrive to disengage in any gear at any speed.

Coming back from Devizes last night, I was cruising at 50-60mph and suddenly the o/d disengaged and the gearknob light came on, as it does if the speed drops below about 30mph.

Experimentation showed that it would throw itself out in any gear, at any speed. It would always engage properly but sometimes disengage almost immediately, other times it would go for several miles before throwing itself out.

Any thoughts?

[yellow]

Probably time for a new speed sensor...

There was a post on here recently with part numbers and all. As I am typing one-fingered (plaster cast-) I cannot be bothered to search for you...

[Dr Goon]

Probably time for a new speed sensor...

There was a post on here recently with part numbers and all. As I am typing one-fingered (plaster cast-) I cannot be bothered to search for you...

I did wonder if it may be a problem with the speed sensor and I will have a crawl underneath tonight to see if it has come unscrewed or a wire has come off. The thing has only been fitted for about 3 months so I would be surprised if something has failed so soon. A search did not come up with any hints.

[Kev Baldwin]

99.9% certain to be speed sensor. Known weakness with the unit. In fact I don't know anyone with a GKN who hasn't changed one of these damn things at some time. Mate of mine who does lots of miles across Europe and Africa in his 110 got so fed up with the things failing he's just swapped his OD to a Disco T-Case to save any more hassle!

[GBMUD]

Am I correct in thinking that one could simply ditch the speed sensor and the control box, wire the switch direct to the solenoid and then use ones own common sense about switching the OD in and out at the correct speed?

Chris

[yellow]

Has anyone got an e-mail address for GKN that is known to work.

Mine started playing up last night so I sent an e-mail this morning to the address that appears at the botton of the spec sheet on the Devon 4x4 website. It bounced. The address was s.goodall@gkndriveline.co.uk.

Any suggestions from anyone on here as to what could be causing the overdrive to disengage in any gear at any speed.

Coming back from Devizes last night, I was cruising at 50-60mph and suddenly the o/d disengaged and the gearknob light came on, as it does if the speed drops below about 30mph.

Experimentation showed that it would throw itself out in any gear, at any speed. It would always engage properly but sometimes disengage almost immediately, other times it would go for several miles before throwing itself out.

Any thoughts?

Have more time today, and been searching...

This is what Western had to say a while back...

Tim, when you phone 0121 1606 it's the sales desk ask for Sue Rowland or 0121 313 1661 and ask for Steve, make sure you have the units serial number to hand, Speed Sensor part number is 119509/00/00, price is £70.50 including vat, changed my sensor as I thought it was faulty and not giving the control box the correct signal, in the end the solly was sticking a new one cured the fault and restored full operation

Hope it helps.

and as GMMUD is thinking...

Am I correct in thinking that one could simply ditch the speed sensor and the control box, wire the switch direct to the solenoid and then use ones own common sense about switching the OD in and out at the correct speed?

This is indeed an option, although I was happy to have the fall back trough the sensor after driving with an engaged OD for 2 hours straight...

Your choice...

[Les Henson]

The instructions for fitting the speed sensor are pretty strict - you must only use thread locking compound to secure it as the distance the face of the sensor is from the gear on the inside of the unit is very important. They warn against using copper washers or similar to seal/secure it.

Gordon - yours is under guarantee as I'm sure you are aware.

When I fitted the sensor, I looped the wire back and secured it to the body of the sensor with a cable tie, then routed the wire so that it was held in the recess of the O/D body. The cable ties that come with the unit rae rubbish and snap very easily. The wire is held securely and will move a small amount, but I'm confident it can't abrade against anything, and the sensor itself is unlikely to come loose - I use the same locking compound for Crankshaft bolts etc.

My only real criticism of the O/D units is really the wiring (or rather the connections). I would expect them to be water proof, but nearly all are not.

Anyway - how your sensor is fitted, and the lay of the associated wires.

The actuating solenoid is right at the base of the unit, and pretty-much in the elements, yet the electrical connections are cheap and nasty. These units are very expensive, and In my opinion the wiring side of it is not suitable.

As far as contacting the company goes - I tried to contact them a few times regarding another matter and got no reply/gave up in the end.

Les.

[western]

Very strange that it's hard to get in contact, I just rang the number in the quote of mine above & spoke to Sue & Steve without any problem.