Author Topic: Filter in Oil Feed Line  (Read 6506 times)

Offline muskrat

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Re: Filter in Oil Feed Line
« Reply #45 on: 27.01. 2011 19:02 »
Nice work Alan, very informative.
                                             I'm still a multi/filter/additive type of guy. I agree that multi's don't last as long, I see my oil pressure starting to drop after about 500 miles. I change it at 1000 to 1500 miles so not really a problem.
 One thing that is confusing is that modern machine manufactures recommend multi, but their oil runs in the gearbox and clutch. Can't get any more chewy than that.
 And what about synthetics ?
'51 A7 plunger, '57 A7SS now A10CR,  '83 CB1100F, 88 FXST .
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Offline Alan @Ncl

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Re: Filter in Oil Feed Line
« Reply #46 on: 27.01. 2011 19:56 »
Thanks Muskrat
Yours is a good point about the 'chewing' in gearboxes etc. and sadly, I can't clarify further  That point about longevity was added onto my original list following my communication with Castrol and I just took it at face value. I know that old BL cars like minis and maxis also had common engine and gearbox but can't recall whether they had to have more frequent oil changes. Richard's point about shelf life is certainly noteworthy too.

The link between cold running and sludging was also added based on the Castrol man's comments.


Offline alanp

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Re: Filter in Oil Feed Line
« Reply #47 on: 14.02. 2011 14:55 »
Further to my post on 20th Jan about the wet sumping you get with 20W-50 oil, I have a more accurate measure now based on a drain of the sump I have just done and the precise number of days it has stood. The daily quantity of oil draining into the sump has been 36ccs.
This is with a new SRM pump and backs up the fact that 20W oils are quite thin at the sort of temps we have had over the last month or so and can be expected to drain past the pump easier than SAE 50 grades. I find this daily 'sumping' value quite eye opening. I don't have a value for SAE 50 grades on this engine for a precise comparison but will bet it's a lot less.
Keep this in mind for when you get the bike ready for the riding season after a long winter lay up. Just drain what's in the sump and put it back in the oil tank.
When I ran a DBD34 500 Gold Star a couple of years back it was a pig to start after each winter lay up and when it eventually decided to start it used to set the smoke alarms off in my garage - I now know why, the oil build up in the sump was dragging like mad on the crankshaft and oil was working it's way past the piston skirts until the scavenge side of the pump eventually got the oil in the crankcase under control.
It would be good to get some figures for 40 and 50 grade oils from others who know the number of lay up days and can measure the quantity drained from the sump.
The sun is shining and my Ducati 999S has been out stretching its legs and growling in delight (or was that me?) and if it keeps this up the BSA will be out soon as well since it seems the road salt has virtually disappeared down in SW Devon.
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