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MG MGB Technical - Best inverted oil filter

I have a 1969 MGB GT with a spin on oil filter mount from a newer car. It is one of the inverted type with the oil 'standpipe' in the middle, that the oil filter sits over.

Up to this year I had been using K&N HP2004 oil filters, and was pleased with them. This year, I ordered another of the same model, to find they had changed the internal design to include a bypass valve (I think) at the top of the filter. This has the effect of reducing the room for the oil pipe, and stops the filter sealing - close, but not enough to stop flood of oil on starting engine!!

I wondered if you could recommend a good filter for using in the inverted way, with enough clearance on the MGB.
No one seems to give internal dimensions, probably because it usually doesn't matter too much.

Valve can just be seen at the botton(top when inverted)

SR Pontee

Try a Mann W917.

C R Huff

I always ask for a Wix filter for a 1985 Volvo 240. I've always found them to work well.
Erick Vesterback

Yup. Even my 99 Volvo V70 runs the W917. Kind of handy since it makes sense to order them by the case since I have a bunch of cars that use it.

C R Huff

I think it depends on what you have and what you wish to have. Some questions.

Does the existing filter mount have an inbuilt pressure relief valve? If not do you wish for one in the spin-on filter? IIRC the original paper element inverted filter mount relief pressure was 17lb. What is the relief pressure in the filter you have?

Is the standpipe removeable? If so would that solve your issue as there is an anti drainback skirt in the filter pictured.

If none of the above works then you need to know the height of standpipe you need to clear (by how much?), the mounting measurements (thread size and sealing ring diameter and whether you want an inbuilt relief valve or anti drain sleeve or not. Filter websites usually give these details for each model eg Ryco does.

I don't know the makes of filters you have available in your market but cross references should be available on any credible filter website.

I think the safest bet is to research filters fitting what you know you need. What works in one application may or may not work in another, depending on the above technical factors.

Happy hunting

R Taylor

Roger. You misunderstand how the system works. The stand pipe, in the middle, keeps the level of oil within the filter up on the egress portion. The anti-drain back valve keeps the oil up in the ingress portion of the filter. Removing the stand pipe would make the anti-drain back valve irrelevant.

I agree with Charlie. I have used the Mann W917 in my MGs for years with excellent results. I, too, purchase them by the flat.

Les Bengtson

It would appear that GSF stock Mann filters.

Here's the Volvo 240 filter...
D O'Neill

G'day Les,

I understand perfectly how the MGB filter systems work in there varied forms.

My contribution to the original poster was in recognition that the comment (however helpfully offered) "with a spin on oil filter mount from a newer car" did not describe exactly which mount was fitted. ie whether in fact it is an MGB mount at all

There are early Bs fitted with spin-on mounts from other LBC applications in addition to those fitted from later Bs. On some of these, mine included, the screw-in mounting thread has been changed to permit a wider range of more common filters to be fitted.

My system has no standpipe but I do have the anti-drain back screen in the screw-on filter (as well as a pressure relief valve). My oil pressure reading comes up very quickly.

My concern with the responses offered was that they all seemed to make the assumption that the posters mount was exactly as theirs is. That may be the case, but there is nothing yet in the posts above that seems to establish that.

R Taylor

Mann 917/1 like the Volvo 3517857-3 reputedly made by Mann is shorter than the original Unipart, Champion etc. filters specified for the MGB. I tried a K&N Gold and it was fine but at about four times the price as the others so it should be.

Mann 916/1 is longer - the same as Unipart etc., so that is the one I use. Internal height is 2.93" going up through the bypass valve spring, which the stand-pipe should do. The stand-pipe on mine is 2" long. The shorter 916/1 is 2.75" internally and the Volvo 2.57", so getting a bit close.

Fram, including GFE121F (the F indicating Fram manufacture) as Fram have a wide range of qualities including filtration medium and even whether they have an internal bypass valve or not and are best avoided. A bypass valve is essential as cold start oil pressure can burst the filtration medium without one Some STP are the same, even though they are apparently made be Champion, so maybe Champion should be avoided. Filter heads for the earlier replaceable element filters should have the bypass valve, but those for the later spin on canisters do not as it is assumed the bypass valve will be in the filter.

A pal gets the Mann 916/1 for us both from his local (Stevenage) Central Auto Supplies at 2.60 plus VAT which is a really good price.
Paul Hunt


Thanks for the info on the filter heights. When you said, "The shorter 916/1 is 2.75" internally and the Volvo 2.57", so getting a bit close." did you mean that the 917 is 2.75?

C R Huff

Ah yes sorry, it is the 916 that is deeper, 917 shorter.
Paul Hunt

Always used Champion filters for my 1973 BGT tried a Fram filter but it took 20/30 seconds to get oil pressure so would not use again.
I now use Mann 916/1 instant oil pressure every time bought off eBay for 2 00 plus 4 00 postage, I bought 3 for 6 00 still with 4 00 postage 3 filters for 10 00
wm griffiths

This thread was discussed between 29/05/2014 and 05/06/2014

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