Filter in Oil Feed Line

[alanp]

Just let me extend the filter subject high jack a little bit more on the oil debate.
I agree with the conclusion that we don't know what is best for our old air cooled engines and I expect this would vary anyhow depending on how they were used re. speeds, ambient temperature, wear condition etc.
In general, it seems to me we should stay away from the 'too thin' area on the graph when the engine is hot, but what is the best method?
Those of us with oil pressure gauges can see the oil pressure falling as the engine gets hotter until the day comes when you question whether the lower oil pressure you see on the gauge, after a good long 20 mile 70mph plus run, is good enough for the engine. I decided it wasn't and fitted an oil cooler. As expected, the oil temperature in the oil tank went down and the oil pressure went up. Relative to the graph, my oil temperature along the bottom axis is now further to the left and the oil viscosity further away from the 'too thin' area and avoiding the drop towards the 'too thin' area. With the 20W50 oil (with a return filter) this should also give me better oil flow at start up from cold and reduce the multigrade deterioration over time due to the lower oil temperature.
Concerning additives - As the ambient temperature dropped with winter approaching last year I noticed that at start up from cold I needed to raise the tick over screw a little to get a reliable tick over for a few minutes until warm which it didn't need previously. I added some ZX1 Extralube to the oil tank as an experiment and found that the cold tick over increased and I didn't need to alter the screw. After the winter lay up I'm interested to see if this is still the case.   

[bsa-bill]

Hi Alan
I tried the ZX1 Extralube in my project as it had a sometimes sticky valve, Have to say I was impressed I did however drain it out after a hundred miles or so thinking it might prevent proper bedding in ( not sure I was right but better safe than sorry),
Now to get back on subject (almost)  thinking about low oil pressure, back in the day most cars had oil lights that came on to warn you of low oil pressure, these (IFIRC) came on at 5LBs  !!!

[lawnmowerman]

Hi Bill

What symptoms did you get from your sticky valve - was it similar to mine in my "Spitback through carb and backfire" topic?
I suspect a sticky valve after the winter layup and was thinking of trying the ZX1 Extralube - where did you buy it?
Thanks
Jim

[Alan @Ncl]

Thanks Lads.  This ZX1 stuff sounds very promising.  Would be interesting to see Alanp's final judgement after startup this year (I think I will change my name to Alan(N) to avoid confusion).  I am very envious of your oil pressure gauge.  Very useful instrument (much more so than the 'too-late' warning light).

[alanp]

I suspect a sticky valve after the winter layup and was thinking of trying the ZX1 Extralube - where did you buy it?

Halfords.

[lawnmowerman]

Thanks Alan

[bsa-bill]

As Alan says Jim Halfords.
and the valve sticking - It was when setting the tappets, the timing side Ex valve seemed to momentarily stick and then came up and make a "click" presumable when taking up the play between pushrod and tappet/cam or cam follower.
Upon investigation I discovered this happened as the crank came round to the point where it was rubbing on one of the long studs for the primary chaincase, This what I put it down to but after reading the Rockerbox article I wonder if I've missed something.
So the plan now is to have a very close look at the valve springs in situ and if it looks like they are binding anywhere I'll lift the box off and engage a Dremmel type thing.

On the subject of Dremmel I see the smaller one is on offer locally (300 is it) - is this one worth buying or is it better buy to go for the larger (4000 I think )
opinions welcome ( sorry Jim getting off subject again)

[nigeldtr]

Alan @Ncl,

Super explanation and graphic.

Nigel

[Alan @Ncl]

Having now benefited from all of your posts, I have finally decided to 'do the conventional thing' and move my oil filter from the inlet side into the return.  Have managed to do this without cutting into the other armoured hose and have also retained the same filter location; underneath. mounted on a bracket off the centre stand stop.  It is retained quite rigidly by by a big circlip (see pics). The filter is a C103 with 3/4 UNF thread and surprisingly, is still readily available at Halfords. Its bigger than the Norton ones bur presumably offers minimal flow resistance.

Took the oil-tank off and gave it a good clean out.  It was absolutely filthy (shame on me) despite having had a paper filter all these years. At least with my previous set-up the engine was protected from anything getting past the oil-tank suction strainer, due to the position of the filter (I am still a bit nervous about removing this backup).  It will be interesting to see if the repositioning reduces such accumulations in future by trapping all this crud somewhere that it is more easily removed (i.e. in the return filter).

I have also decided to stick with the expensive Silkolene 40 monograde that I bought, partly because its paid for (the scrooge in me) and partly because it 'looks and feels nice'.  Not the most compelling justifications I grant you but since there was no clear majority for switching, this was the path of least resistance. At least this stuff is true grade 40 rather than basically a 20W with additives to reduce its propensity for viscosity reduction at higher temperature (thanks, by the way, to Nigel for your kind comments on my previous post).

The moment of truth draws closer but before firing up, I may have one more new thread to launch.

[Alan @Ncl]

All seems to be quiet on this front lately (only me posting so hope I am not overstaying my welcome).  I thought it might be worth trying to pull together all of the various contributions made on this topic in the form of a table (see attached).  This comprehensively lists, I think, all the various factors raised for consideration by your various posts.  It then lays out alongside each one, features of Multigrades and Monogrades for comparison.  No real conclusion defining which is ultimately best of course but depending on your primary concern, may provide a useful summary of the arguments for and against, all on one page. 

I had an email exchange (see footnote below) then a chat with the Castrol Classics tech guy who was extremely helpful.  He kindly read my table over and offered a few comments but did not take exception to anything that is included here.  He did point out that while monos do contain some detergent, its very minimal compared to multis. 

I hope this table may prove useful, especially to newcomers wanting a quick intro to the debate.

Initial Email Reply from Castrol:
The current Castrol recommendation is Castrol Classic XXL40, however as you have the in-line filter then you will probably benefit from the Classic XL20w/50. The one thing to take into account is that with roller mains the chewing action of the rollers on the multi-grade will reduce it's viscosity over time, so change the oil every 1000 miles and you will be fine. Monogrades (XXL40) are not affected in this way and retain their viscosity even when due for change.

[lawnmowerman]

Thaks Alan - really useful summary. I have just changed the oil and used some GTX 20/50 that has been in the garage for a few years. As others have said, the main thing is to change it regularly rather than be too worried about the maufacturer. Personally, with a rebuilt engine I will stick with 20/50 but a filter and OPG is on the "to do" list.

Jim

[Alan @Ncl]

Thanks Jim.  Sounds sensible.  I attach a pic of my filter as now refitted on the return side, underneath in the airstream (sort of).

In passing, I tried a crude test watching the run down from the tank under gravity though the flexihose, with and without the filter in the engine feed line (before changing over).  This was with the fresh Mono40 grade (very thick at current Newcastle temperatures).  Did not look much different with and without the filter. Concluded the filter did not pose an obvious increased resistance to flow under these conditions (a pathetic dribble in both cases) but this was hardly a solid 'scientific experiment'.

Alan

[orabanda]

Just a note about (any) oil; shelf life is around two years. After that degradation of the additives due just to aging means that it no longer performs as when originally mixed.

Use your oil within two years of manufacture date, before its properties permanently change.

My research (after the same soul searching that everyone else has gone through) is that Penrite Enduro (check out the product on their website) is the best choice of multigrade for my A10's (and XT500). Note the high zinc content, which helps reduce wear at high load contact surfaces such as cam lobes and followers.

Some multigrades have significantly less zinc content.

I use return filters of my own design in all the A10's.

Richard

[A10Boy]

I used to have a Hardly... Sorry... 

The oil for that was made by Penrite according to the dealer, it was a 20-50 with high zinc content. So for UK users if we want Penrite 20-50 you can buy it from a Hardly dealer.

[lawnmowerman]

Hi Richard

I did not realise that oil had a shelf life. My logic was that it had been in the ground for about 25 million years so another 25 years in the garage should not make all that much difference - forgot about the additives 
Live and learn

Jim