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MG MGB Technical - Oil filter

I have just purchased a 72 MGB. I want to change the oil. But I'm not sure which filter to use. There is just a generic "Quality Filter" on there now. I have read that K&N are the best filters to use, but not sure which one. Anyone have any suggestions? If it matters, the filter is an inverted filter.
TRH Hammond

Also, I think it's 10w-30 or 40, Casterol I'm it now. Should I switch to 20w-50 like I'm my TF?
TRH Hammond

The factory recommended anything from 10W/40 to 20W/50 for temperatures above -10C. 10W/30 is for temps down to -20C so probably too low. However these days anything lighter than 20W/50 has less ZDDP which can hurt cams and followers, so it's best to stick to 20W/50. The earlier the API specification the better, SJ used to be the best, you may have to go with SL, but avoid SM.

The one filter that many people say not to use is Fram, as they make some really cheap stuff. Mann 716/1 is a good filter at a very reasonable price here in the UK. After that the price can progressively go up to three or four times more for Volvo and K&N Gold for example, but you are unlikely to be getting much by way of a better filter.

What differentiates the good from the "not so good", besides the filtration performance, is the effectiveness of the anti drain down valve at the thread end of the filter. The good ones (Mann) don't allow the oil to drain out to the sump. The effect of a poor valve is start-up and running without oil pressure for, what seems like, a dangerous, wearing time.
Allan Reeling

Does K&N offer an anti-drain filter?
TRH Hammond

I use the Bosch 3500 filter and highly recommend using it.

You can get them at Autozone.
Steven Rechter

The K+N filter has an excellent anti-drain back valve. I use a Wix filter on my B. NAPA carries them as their name brand filter under part #1016. RAY
rjm RAY

The K&N oil filters are excellent - I have used the inverted version ( HP1002 on my '72 18V for years - the HP1002 is a thinner version but it fits in the engine bay of my 57 MGA). I also run Mobil 1 15w50 with added zddp (Moss) for better top end protection and easy staring on the very cold winter mornings on Northern PA - I suspect that winters aren't too mild in NH either.
Bayard DeNoie

run Castrol 20-50 through your engine and all will be well.
Rob C

2X the 20w/50 Castrol GTX. Can't go wrong
S Nott

Mann W917/1. And it is readily available at Volvo dealerships in the U.S.

The Mann has an anti-drain back valve and is the only filter I have found to actually provide near instantaneous oil pressure. Other brands have the valve but they don't really work well. Over 30 years I have found proper functioning of the valve to be a crap shoot.

This is why the Mann is the only filter I use.
Richard Smith 1

This thread was discussed between 16/05/2016 and 22/05/2016

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