Diff too full - ? - any advice welcomed

[PhilB]

Although had car 2 years now, finally just got around to checking oil level in diff. (The Filler Cap on the offside side of the diff was a bit chewed up when I looked last year so put it on 'todo' list - it got to top of list today so tried again and eventually go it out.) Only to find oil pouring out. After about 1/5 pint on the garage floor I put the bung back in and finger tightened it back up.
Presumably it should not be so overfilled.
How can it have happened? What would you do about it?

[72BLUE]

How can it have happened? What would you do about it?

My guess is that it was filled up when on axle stands or a pair of drive on ramps, ie not level?

Keith

[GDPR]

That sounds about right to me too Keith...

Get the car level and let it drain to the correct level, Phil

[HersnotHis]

Presumably it should not be so overfilled.
How can it have happened? What would you do about it?

Firstly check that you have filler plug level with diff both side to side and back to front. Unless it was hot when checked any excess should not "pour out" it is SAE 90 or 95 and should creep, fall or or "well" out at most.

Most important check however is ensure breather valve on top of diff is free to move up and down as otherwise if blocked/jammed pressure can build up in diff which could give rise to expelling of oil particularly if duff is not level (back higher than front)

I had a diff with a small leak and found that on inspection the breather was blocked . I then decided to drain the existing oil repeatedly using compressed adapted 500 ml PET drink bottle. I the refilled the same bottle with new oil and squeezed it in. Have now realised that I can get a Sealey Oil Syringe/Pump for about £8 on Amazon to make this job (and others!) easier.

HTH

H

[PhilB]

Thanks Everyone for your comments
I will check the breather tomorrow - I haven't!!! Did Not know there was one!
Car is in garage on own wheels on good flat surface so level f to b and s to s
It was also cold i.e. not been run for a few days.
Oil seemed thin to me as well compared to an SAE90
Is there an easy way to drain "In Situ" and refill - Can I just take the back off fairly easily?

[GDPR]

Disagree entirely H. Don't know what oil, grease or molasses you put in yours, but unless you are at 10 below zero the correct oil comes out at a very decent pace.

I do this for a living Phil....thin sounds about right - it stinks and is usually a multigrade Hypoid oill so thinner when cold than you would think

[HersnotHis]

Disagree entirely H. Don't know what oil, grease or molasses you put in yours, but unless you are at 10 below zero the correct oil comes out at a very decent pace.

I do this for a living Phil....thin sounds about right - it stinks and is usually a multigrade Hypoid oill so thinner when cold than you would think

Will check but but think last refill after clearing vent was Comma SAE 90 - when cold I would not say its Molasses or treacle but definitely syrup in comparison to engine oil. It does not pour it maybe flows (slowly?)

Not been in trade but think I first refilled a "friends" Diff with Castrol Hypoy 90 in about 1961?

Furthermore it is difficult to raise any filler much above horizontal (in situ) and therefore a pressure assisted filling is advantageous.

H

[Staggard]

"Not been in trade but think I first refilled a "friends" Diff with Castrol Hypoy 90 in about 1961" Aitch you are my man Russ its time to step aside in the words of Mr Sugar You are fried

[XFSTag]

I have recently had issues with the breather on my TVR's BTR diff and I can agree with Russ it definitely runs out
All over my sodding driveway!

Cheers
G

[PhilB]

Can't find a breather on top of my diff - Any photos showing it?. The oil that came out is runny but fairly thick and has a very powerful smell.
I checked ratios last year by marking prop shaft and turning a road wheel round etc. and it came out as a 3.45 to 1 OK. However no letters/numbers visible on it !

[Guest]

The breather is a small hole with a pin in it, the pin looks like a large hair clip? You should be able to move it up and down.

Jason

[PhilB]

No Pin - diff covered in crud/waxoyl - whereabouts would I find the (blocked?!) breather hole - e.g. n/s o/s top front or back

[DJT]

http://socforum.com/forum/showthread.php?23804-Gearbox-and-Diff-breather-holes&highlight=Diff+breather

Julian's Picture in post #8 shows where it is.

[PhilB]

Many Many Thanks - Picture worth 1000 words true again. Been under again and Hole found, clear or cleared, No Pin!
Happy Bunny Now

[HersnotHis]

Many Many Thanks - Picture worth 1000 words true again. Been under again and Hole found, clear or cleared, No Pin!
Happy Bunny Now

Hi

With no pin I would be concerned that at full running temp oil would be expelled via this vent?

TBH not sure how this valve is supposed to work but since I cleared mine the Diff leak has reduced considerably. Perhaps somebody can explain how this valve is intended to operate?

H