Oil consumption

John Murch · Posted: Sat Sep 02, 2017 9:32 am Post subject: Oil consumption

While looking at the TF's, I noticed that Oil consumption for a 4 1/2 is shown as 1,200mpg, and for a 3Ltr 800mpg.
When my car was a 3Ltr I never had to add oil between 5000 mile services, although I expect it may have used a pint. Now on 4 1/2 ltr I use more, perhaps a 1 1/2 pints per 1000 miles.
Would this apparent improvement be due to better piston rings, smaller bore clearances, or.....? Or changes in the actual oil, and if so how?
Or perhaps it just leaked out!

Chris Card · Guest

John - like you, my oil consumption is minimal - except for what still leaks out!!

Chris Mr. Green

Robert Clifford-Wing · Posted: Mon Sep 04, 2017 11:11 am Post subject:

As per Chris's comment, most of my engine's consumption is leakage, with a bit being burned. I have a leak around the front-end of the engine, up until now it has only really messed up the nearside of the top of the sump casing, surrounding the oil pressure/pipework. As one who has never seen a 3 litre engine out of its mountings; what are the possible leakage areas and, might there be any simple cures as I fear a main bearing oil seal and possible 'engine out' scenarios, if one were talking modern engines?

At some stage the radiator needs to be removed for soldering and also water pump attention but curiosity is getting to me!

Robert Craven · Posted: Mon Sep 04, 2017 1:20 pm Post subject:

Rob,
Could you clean the area surrounding the leak and then when it begins to re-appear take a photo and post it to help people give you suggestions what might be causing it?

Chris Card · Guest

Hi Rob - I also have leakage into that area and, as Liz keeps telling me, a little oil goes a long way, especially on my trousers!
Difficult to tell exactly where it comes from, but some is blown out of the oil filler, a bit comes from the turret joints, but I suspect the main culprit is the thin gasket under the front of the block. Oil surge on braking must put quite a lot of pressure on that joint.
Apart from the turret and cam box there is no oil above the base of the block.
Chris

John Murch · Posted: Tue Sep 05, 2017 4:19 am Post subject:

My main culprit is the joint on the turret, which seems to defy my attempts to cure it.

Robert Clifford-Wing · Posted: Tue Sep 05, 2017 8:23 am Post subject:

Iain Warner · Posted: Tue Sep 05, 2017 10:15 am Post subject:

At the moment I am trying to cure an oil leak from the front of the engine. On first inspection I thought it was from the crankshaft seal, (this was modified some time ago to fit a lip seal in place of the acme scroll). Replaced the lip seal and moved the starting handle dog forward slightly by fitting a spacer so the seal now runs on an unworn surface.
Result - still leaking - but this time seemingly from around one of the four nuts that hold the nose piece for retaining the meshing plates in position. This was addressed by fitting dowty washers behind the nuts.
Engine not leaking as much as before, but am still getting oil collecting at the base of the front chassis crossmember and dripping onto the track rod. Today I am renewing the cam cover paper joints as there has been a little oil running down the turret, both above and below the seal ring, to see if this will stem the flow a bit further. (and might as well check the rocker clearances while I am at it). As you say a little oil can make quite a mess.
Previously my oil leaks tended to collect on the nearside flange around the oil filter, but recently seem to run down the front of the sump.
Will report back in due course.

Stephen Blakey · Posted: Tue Sep 05, 2017 11:57 am Post subject:

Apologies if this reminds you of grandmothers and egg sucking, but the standard way to search for elusive leaks is with fluorescent dyes e.g.;

http://www.ebay.co.uk/itm/UV-Dye-Torch-Kit-Leak-Detection-Dye-For-Oil-Fuel-Petrol-Diesel-Leaks-RLD4-/230754744531?epid=2077216904&hash=item35ba0df8d3:g:e1MAAOSw44BYWmMp

There might not be enough in that kit but there's plenty of other sources on eBay.

Robert Clifford-Wing · Posted: Tue Sep 05, 2017 12:55 pm Post subject:

Do any members know of an 'exploded' diagram of a W.O. engine?

Iain Warner · Posted: Tue Sep 05, 2017 1:37 pm Post subject:

My leaks only tend to manifest themselves after a lengthy drive, when everything has got hot and by then the leakage gets spread around hence the difficulty determining the exact source. On cleaning up and watching for further leaks with the engine running sods law dictates that there is no sign of oil. I suspect there are actually several leaks of varying magnitude and my best hope is to stem the worst of them. I have not used the fluoroscene type leak detector, but worthy of consideration, thanks Stephen.

John Murch · Posted: Wed Sep 06, 2017 10:03 am Post subject:

May I nudge the conversation to oil consumption, why did cars in period use so much oil? I'm sure they leaked, but not a gallon every 1000 miles

Iain Warner · Posted: Wed Sep 06, 2017 11:17 am Post subject:

I think a lot was down to the pistons used and the clearances. Especially the hour glass pistons originally fitted.

Stephen Blakey · Posted: Wed Sep 06, 2017 7:10 pm Post subject:

It's got to be due to improvements in the understanding of how the ring-pack functions, in this case the oil scraper particularly. Companies like Hepworth & Grandage, as was, had departments of boffins tweaking the designs and testing engines looking for small improvements over the decades since WO's engines were designed, and some of those improvements will have found their way into the aftermarket.
BTW, did anyone else notice that the oil consumption figures quoted above are in exact proportion with the engine size?
Apologies for the clunky wording. I'm typing this on my phone and it's too laborious to edit it.