Gearbox oil leak - concerning?

[mph]

Hello folks,

I've noticed a wee leak from the gearbox this morning. Normal and acceptable, or something to start fretting about? It's an R400 Duratec with the 6 speed box.

Thanks for your thoughts

--Mark

[ScottR400D]

I assume that's coming from the rear seal and running forward down the housing?

My 2015 R400D has always done that but it amounts to two or three drips on the garage floor over the summer and has never been enough to noticeably lower the level in the box. 

Incidentally, I had my prop out last year when sorting out the diff. Since I replaced the prop into the same seal there's been very little leakage; no drips at all but still a smear on that casting!! 
 

[mph]

It was a very small drip on the floor Scott, so you've maybe hit the nail on the head. If it's just a case of "they all do that sir" I shan't fret.

Thanks!

[aerobod - near CYYC]

I've had a couple of drips from the tail shaft seal in the past, but currently it is dry. Much like the weeping from the diff driveshaft seals that some people experience, I would say slight seepage is pretty normal.

[Nick T]

Sorry to say my R400D with a 6 speed does have the odd drip on the floor, however the level has never been low when checked. It is so small it has never really bothered me. 

That said there is an argument that in this day and age it should be dry

[Geoff Brown]

My 6 speeder used to deposit a few drops of oil on the garage floor once in a while especially after a really long run. But then sometimes it did not. As with Scott R400D the casual drip has stopped after my diff job....strange.

A couple of occasionally drops is nothing to fret about. Just monitor the garage floor & as always check the gearbox oil level at the annual service. 

A tale from 'when I' : 25000' mid Atlantic going West. Looked out of the cargo window to see hydraulic fluid streaming out of the prop. Made it to Gander but the oil had reached the tailplane - that is the time to panic - & the prop reservoir had less than a litre remaining. Like spilling blood a little looks a lot. The same with oil unless it is obviously pi*sing out.

Topped up the prop & continued on route until warmer climes 'healed' the seal up. Got me home two weeks later.

[mph]

What a fabulous tangent to a dripping oil question Geoff Brilliant!

Thanks all for the reassurance. All good 

[ScottR400D]

#6, great story Geoff, and puts concerns about a few drips from the tail seal of our fun cars into some perspective! 

I remember one of my first flights, from East Midlands to Schipol in the '70s in a Viscount that was streaming oil from the engine just outside of my window. I mentioned it to one of the cabin crew who basically said TADTS!

Where've I heard that before?! 
 

 

[SM25T]

#5 .... I think MoT test doesn't like leakage of fluids these days.

[Geoff Brown]

#8 ScottR400D - Typical early British engine - total loss oil system. All British motor bike engines used to be like that so no chance of the frame corroding.

#5 SM25T - MoT rules apply to leaks & continuous form of heavy weep but not so for a slight weep according to my MoT inspector. 
 

If worried about a slight weep prior to the MoT reach underneath & give the area a wipe. The car will not travel far to the ramp so all should be well. 

[Beagler]

Is this not an easy fix. Remove propshaft prize seal out carefully tap in new seal replace shaft.

[Beagler]

Is this not an easy fix. Remove propshaft prize seal out carefully tap in new seal replace shaft.

[ScottR400D]

Beagler, yes in theory but it's not that easy to press the seal in squarely even on a ramp. 

As you can see in the earlier pic there is a chassis member runs across close to the box tail and it can impede access. 

Another thing to consider, and as I understand it, the seal is the type that throws the oil away from itself when it's running but is almost bound to weep a little because it is lubricated by the oil it's keeping in. That weeping becomes evident just after you stop.  

I'm aware of seals that have leaked badly and needed replacing and lots seem to have slight leaks. 

I'm also aware of cases where the seal has been changed but there's still a slight leakage with the new seal so as long as all mine needs is a quick wipe every couple of months I'm happy. 

By the way, to remove the prop you have to first remove the diff, after removing the drive shafts, A frame, ARB, brakes.......... 

[Beagler]

The reason I suggested it may be easy ( may not be on a Caterham) is I changed many of these in the old Fords in the late '60s as a Ford mechanic. I used these. But have used other methods. It is better to add a little sealant to the gearbox seal housing as small weeps come from seal to housing fit.

[ScottR400D]

In my case the weep is where the seal contacts the shaft. I've not heard of any 7 6 speeds losing oil round the outside of the seal. 
 

[Beagler]

Once the seal is replaced there should be no leakage at all with modern seals. 

[ScottR400D]

Well, the seal's only one part of the equation but if you can find one that seals completely, I'd be interested to hear about it, as would others, I'm sure. 
 

 

[Beagler]

What sort off mileage do the seals start leaking. The old cortina/anglia boxes would probably last till about 20,000 before leaking. Breather blocked didnt help.

[7 wonders of the world]

you also need to consider the condition of the prop nose where the seal runs otherwise the new seal dosen't stand a chance

[Beagler]

Yes Ive seen them with quite a deep groove encircling the yokeend shaft.

[ScottR400D]

#20 On a 7? 

[Beagler]

Not on 7's but early Fords in the late '60s

[ScottR400D]

I doubt that's a reasonable comparison, really.