The BSA A7-A10 Forum

Technical => A7 & A10 Engine => Topic started by: mikeb on 02.02. 2017 10:21

Title: is this an oily good idea?
Post by: mikeb on 02.02. 2017 10:21
this is an anxious oil question about my 61 super rocket

i'm about 1500miles past a full rebuild - everything inside the engine including oil pump (srm) and sludge trap.
the first 500 miles were without a filter to settle in. then I added one (spin-on cartridge).
I've been running Morris 40 golden film 'classic' oil. So far all good.

Now I've been reading too many oil threads and decided I'd like to put Penrite HPR30 in it as its a high zinc 20w60 - our Aussie friends appear to like it. also with its modern detergents (or whatever they are) it will carry the crap to the filter. and the zinc can help my refaced cam followers.

BUT! as the first 500 run-in miles were without a filter (I assume when initial wear occurs) should I be concerned that's there's already enough crap in the new sludge trap just waiting to free itself and race straight to the new timing side bush to attack it?

so, to change (to Penrite) or not? what do you think?

Thanks

Mike
Title: Re: is this an oily good idea?
Post by: stu.andrews on 02.02. 2017 12:28
I'm interested to read what others might say on this as it's a valid point. My own feeling is that so few miles have been covered &, as you have already run with an in line filter, no harm will be done. But, I'm waiting to see what other members might say.
Title: Re: is this an oily good idea?
Post by: RichardL on 02.02. 2017 13:58
Have you guys read this post from Trevor (BSA_54A10):

http://www.a7a10.net/forum/index.php?topic=10886.msg81607#msg81607

...or others in that thread?

Richard L.
Title: Re: is this an oily good idea?
Post by: edboy on 02.02. 2017 17:53
i always thought that when the sludge trap blocked up it would starve the d/s big end of oil as that is the hardest part for the pump to reach and pressure. i think your being too paranoid . wear on the timing bush is the main crank destroyer.
Title: Re: is this an oily good idea?
Post by: muskrat on 02.02. 2017 19:05
G'day Mike.
Go for it. After only 500 miles the trap would still be clean as a whistle.
For summer over here I go one grade thicker again Penrite 25/70 full zinc.
Cheers.
Title: Re: is this an oily good idea?
Post by: BSA_54A10 on 03.02. 2017 10:13
Sludge trap is good for 30,000 miles which is the recommended intervals between cleaning.
As Musky said it will be clean.
Unless you are running very rich or lugging he engine excessively there will be no sludge in there.
And no Madge, the detergent will not flush it out and make your hands soft to boot  *smile*
Title: Re: is this an oily good idea?
Post by: mugwump on 03.02. 2017 14:55
I don't quite understand the logic of running ( running-in) a re-built engine without a filter! I would have thought that this would be the very time any swarf or such like would be produced from bushings, gasket or sealant or any foreign matter that may inadvertently have entered the internals on re-building.
Of course I'm probably wrong, again!
Title: Re: is this an oily good idea?
Post by: RichardL on 03.02. 2017 15:28
And no Madge, the detergent will not flush it out and make your hands soft to boot  *smile*

I was a bit surprised with the reference to the "you're soaking in it" ad. On checking Google I see it was also iconic in Oz. interesting.

Richard L.
Title: Re: is this an oily good idea?
Post by: mikeb on 03.02. 2017 19:01
Quote
"you're soaking in it"
..was iconic in NZ too. what would the kids think of that today?
Quote
I don't quite understand the logic of running ( running-in) a re-built engine without a filter!
I get your point - me too. The engineer guy helping me with the rebuild was of the mind that you change one thing at a time and make sure it works with the assumption the original engineers had worked out a viable solution. that's ultimately why I didn't do a timing side conversion either - he'd had a devimead one that went wrong.. so it was a conservative approach, and so far the engine is running well

So I'll go get me some Penrite. thanks for your comments guys
Mike