Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Morgan Plus 4 - Drive train noise

I was rather hoping that this thread had been put to bed but sadly......

I now have an oil leak from the gearbox - without even using the car since it came back from the dealer.

Fresh clean oil droplets appear at the lowest point of the casing just below the oil drain plug - not a lot but enough to leave a 15cm deposit ring under the car after a day or two standing. I have wiped the area in case it was just excess oil on the casing from the dealer oil change but two weeks on the seep is still evident.

I have checked the plug as best I can reaching under the vehicle, leverage on the Allen Key is not great but the drain plug does seem tight. Can anyone advise if the drain plugs have a washer or rubber seal? At present it is the only thing I can think of that might be faulty.

Informed the dealer....and still waiting for a response.

Not sure about that gearbox, which I think is Ford? The Mazda box in my Plus 4 has a large conventional bolt head drain plug with a metal washer, but when I took it off it was smeared with 'red hermatite'.

The quick fix would be to slacken it off as much as possible without losing the oil, then a shot of brake/clutch cleaner followed by a quick smear of sealant (I'm not a fan of red hermatite by the way - but there are other products available) - then tighten up. If that doesn't work then it may need the oil dropping. The big problem with drain plugs is that it's so difficult to get the threads clean. Some of the Ford sump plugs have an integral rubber seal and they are designed to be one use only - although so far I've got away with re-using!

DaveW: Thank you very much for your response.

Yes, the gearbox is the Ford one with a pretty standard looking drain plug with a flush Allen Key fitting. I guess the only way to find out about the type of seal is to unscrew it as you suggest - and drop the oil.

The plug seems tight when checked with an Allen Key - in fact the old paint line up markings to show no movement are in line - but if the seal is shot or there is grit in there somewhere then I'm sure oil will seep through.

It wasn't leaking before the dealer did the oil change which is why my major suspicion is the washer/seal on the drain plug.

Am I correct in thinking that when you say the Ford Plug has an Integral Seal the only way to replace it would be with a complete new Plug?

I would call the dealer and talk to him about it.

Yes but Allen headed plugs don't have seals in my experience, only the ones with bolt heads - some of which have an integral washer.

Thanks DaveW - I see your point about Allen Headed Plugs....just thought that there might be something along the length that perhaps acted as an integral seal.

I finally managed to speak to someone at the dealer today.....and am now waiting to arrange for the car to be collected and inspected. Hopefully they will get to the bottom of the issue quickly - I hope so anyway!

Will keep the forum posted.

Some gearbox plugs are taper thread so progressively tighten and seal. The trick though is don't overtighten and strip the threads.

Classic Mini sump plugs were straight threaded but very easy to strip - but easy to helicoil. And usually dripped.

The gearbox level plug on my P4 is taper thread, but the drainer is a straight thread.

The sump plug is straight thread with an integral washer and seal.

And so on!

I just love the simplicity of all this.....I feel as though I have entered another universe.....armed with 'the only drain plug in the village'....

It's a drop in the ocean........

Hi Muck Adam,

Drain plug washers deteriorate when they are of aluminium and re-tightening a few times causes distortion and fracture. Its then worse than having no washer. I sometimes use plumbers PTFE tape wrapped around the outer circumferance and a short way up the thread of the drain plug. This will not leak but don't cover the thread all the way in.
I have also replaced the standard drain plug with a Gold AP-10 magnetic drain plug ( as per my old BMW motorbike) . Metalic wear in the form of a very fine black sludge can be cleaned off the plug at each oil change. Wear is reduced because the oil is constantly being cleansed as it passes across the magnet.
The Morgan handbook specifies Lodexol Morris FS75W90 and 1.7 Litres. Question your garage as to the quantity charged for ! (5 Litres is a mistake)
I hesitate to say this - but not all garages give satisfactory service and it may be necessary to give the thumbs down to this one.
Its quite normal to hear a slight whirring from the idler gear. I am one of those who says no to additives - not much better than wrinkle cream. Get Mucky Adam and enjoy your Morgan
Graham ..