Joined: Dec 2017 Posts: 1,131 Threads: 66
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Location: Nottinghamshire. Robin Hood County
Car type: Austin Ruby Mk1 1935
UjUnder I know this question has been asked and replied to before but although I made a note of things and kept it with my Austin Seven technical data. Do you think I can find it put it down to age.
My question is how much oil do I put in the gearbox of my 1935 Ruby. It is a 4 speed box. I can't recall if it is half or three quarters of a pint. I don't want to overfill it and get oil all over the clutch etc. Thank you all in anticipation.
John Mason.
Would you believe it "Her who must be obeyed" refers to my Ruby as the toy.
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Location: Cheshire
Hi
Best to look at thread 'Clutch Slip' from 2 Aug 2015 on old forum - see replies by Dave Mann and Vince Leek.
Filling 4-speed box to bottom of filler hole is likely to lead to oil getting on the clutch linings, unless an effective seal is fitted. I run with a reduced level in the box, which corresponds to 1 pint according to the above post, and no longer suffer a slipping clutch.
Colin
Joined: Aug 2017 Posts: 982 Threads: 97
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Location: Cheshire
These are the items from 2015, so you don't have to search for them:
Dave Mann said:
Whenever I get a new gearbox of unknown provenance, I take the lid off, drain it and if it looks OK refill it and give it a spin test at 500 RPM on my lathe for about half an hour. I then drain it and examine the drained oil for debris, if there is non and it didn't make an unwanted noises it is put into stock.
I was given a 4 speed 2 syn box this week and remembered this thread and carried out a oil level test:
¼ of a pint - the oil level is barely up to the gear level with only a few drops being thrown up - too low
½ pint - at this level I needed the top on the box to prevent oil being thrown all over my bench.
2/3 pint gives 2” of oil in box measured above the drain plug
3/4 pint gives 21/2” of oil in box measured above the drain plug and 15/8” below the top of the oil filler hole
1 pint gives 3” of oil in box measured above the drain plug and 7/8” below the top of the oil filler hole
11/4 pint gives 31/4”” of oil in box measured above the drain plug and level with the bottom of the oil filler hole.
The measurements were taken with the gearbox top off on the end of the lathe bed, (see photo, the brake drum allows me to put some load on with a piece of 3” x 2”) very difficult in the car.
Then I borrowed my mate's RP saloon handbook 1095A from which I quote on page 15;
Monthly attention
1) examine the oil level in the gearbox which should contain 2/3 of a pint or measure 2” to 2/12” deep.
Then I looked at The Austin Seven Book sixth revised edition by Nicholson page 64, from which I quote:
The gearbox should carry a little over two thirds of a pint which will give a depth of rather more than 2 inches.
On the nearside of the gearbox you will find a plug 2K 8648. When the plug is removed the level of oil in the box can be verified. It should rise to where the base of the plug rests when in position. When refilling the gearbox simply pour in oil until it overflows at the inspection hole.
Finally the Pitman's book of the Austin Seven And Eight third edition reprinted 1951 page 16 from which I quote:
Remove the combined level & filler plug, if this has not already been done and fill up with a pint and a half of new oil which is in readiness. This should give an oil level up to the bottom of the thread in the plug hole.
If you follow Nicholson's advice , until it overflows the inspection hole the first & third motion shaft bearings will be flooded (see drawing) and I wouldn't be surprised if return scroll is overwhelmed and oil found it's way into the clutch. I like Nicholson's 'a little over two thirds of a pint' (how little?) and Pitman has found that the Austin recommended oil quantity of 2/3 of a pint needed to be increased to 11/2 pints for some reason that is lost in the mists of time.
I leave it up to you to decide how little over two thirds of a pint you put in your gearbox.
Vince Leek said:
Dave Mans entry regarding a 4 speed box is very interesting. I have just carried out a similar exercise with much the same results.The conclusion was that The minimum quantity is 1/2pt. This ensures all lay gears are sitting in oil. (this is the level I use when racing and never had a gearbox failure) The ideal level seems to be between 3/4 and 1pt. (.5 ltr) The Austin Ruby Hand book and the Castrol chart says 1.5Pt but this level seems too high and I would not be surprised if leakage occurred.
I don't trust the Castrol chart as it also tells you to fill the rear axle to the level of the filler plug which on later cars is almost at the top of the axle case! I find about 1/2pt (300ml) is adequate for all rear axles.
Vince
Hope this helps.
Colin
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I put 2/3 pint in my 3 speed box last year following the lubrication chart and shortly after started getting clutch slip. I've just changed the linings and plan to refill the box with 1/2 pint of oïl which I think is recommended now. Does that sound right for a 3 gate change box?
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Location: Scottish Borders
The early engine dipstick also works as dipstick for the 3-speed box.
Jim
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Location: Nottinghamshire. Robin Hood County
Car type: Austin Ruby Mk1 1935
Thank you all seem like half a pint and check regularly will be the safest option.
John Mason.
Would you believe it "Her who must be obeyed" refers to my Ruby as the toy.
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just revisiting, having topped up with 2/3 pint in a 3 speed box.
Shall I drain a tad out?
(There ought to be Friends forum sensible recommended levels for 3 and 4 speed boxes "as long as regularly checked" etc etc. if all can agree what that is!)
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Just re-read this thread and realised that its still very difficult assessing the level of a 4 speed box IF the oil is in!
What do people use as a visual check?, as 1 1/4 pints is plainly too much (level of bottom of filler hole) but at 2/3 pint you cannot actually see any oil through the filler....
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I use the engine dipstick for a three speed box and fill to just below the threads of the filler hole in a four speed box.
I have always used this method, never ever measured the amount going in and never ever suffered any issues.
I hope it works for you too.
