Spin on Oil Filter with non return flap

[GTJones]

Hi Guys

Some advice, changed the oil on the car and noticed that the oil filter supplied had a non return flap in the filter? The old filter was a Crossland 2022 without non return flap. Is it OK to use an Oil filter with a non return system, noticed that the oil pressure on tickover is lower than when the 2022 filter was fitted.

Gary

[Lingen]

Gary. I'm pretty sure the non return flap is only there to stop the filter draining back on installations where it is "Upside down" or horizontal when the engine is not running. As it will be in a position on the Stag where it can't drain back, this component won't be necessary.
Mike.

[Stagsongas]

That's a good point Mike, thought along those lines when fitting the spin - on last week.

It has cured the oil leak I used to have, caused by the old Austin 1100 and early Allegro paper element type filter, but sadly I now get to figure where the remaining leaks are coming from....

GTJ ;

Could the lower pressure reading just be the result of a different brand of oil?

Regards

Steve

[jbuckl]

I think you may be referring to the bypass valve, which allows (unfiltered) oil to still flow if the filter gets blocked

[Lingen]

Steve. Other favourite leaks come from the "O" rings in the transfer housing, the oil pump and sometimes the pressure warning switch. Or even the r/h cam cover which will finish up in that area as well. Wash it all off and I expect you will find where it is coming from.. I think it is unlikely that a different filter will alter the oil pressure, but a different oil might. I assume you always use a 20/50 grade? A thinner one will lower the pressure (also a cheap one!)
Mike.

[GTJones]

That's a good point Mike, thought along those lines when fitting the spin - on last week.

Could the lower pressure reading just be the result of a different brand of oil?

Regards

Steve

Hi Steve

Same Oil VR1 20/50? - will put the old filter back on to see if there is a difference?

Gary

[Lingen]

Gary. I don't think it is a good idea to put your clean oil through the old filter. You could try another new one though. I have always used a VW one, which is a VFL117 from Motaquip, WL7070 from Wix, or Z1232 from Coopers.
Mike.

[GTJones]

Thanks Mike

Will see if i can get one locally, do you know if the have the non-return valve fitted?

Gary

[Stagsongas]

Steve. Other favourite leaks come from the "O" rings in the transfer housing, the oil pump and sometimes the pressure warning switch. Or even the r/h cam cover which will finish up in that area as well. Wash it all off and I expect you will find where it is coming from.. I think it is unlikely that a different filter will alter the oil pressure, but a different oil might. I assume you always use a 20/50 grade? A thinner one will lower the pressure (also a cheap one!)
Mike.

Thanks Mike,

I'll be doing just that. I'm trying not to think of the obvious, i.e. that the leak was somewhere higher up all the time, and simply running down the old filter unit!

I'll be checking as you suggest.

As an aside, looking at the data sheet for the spin-on (kit no. FC 292) it states 'We recommend oil filters with 3/4" UNF thread and anti-drain valve, e.g. Fram PH 966'. I guess this may simply be for another application, as the kit also fits the TR7 and maybe other engines with horizontal mounting.

A web address is also given (not tried it yet) which is www.thinkauto.com

Regards

Steve

[Lingen]

Gary. I don't know about the non-return valve, but as I mentioned, it isn't necessary on the Stag anyway. They should however have the internal bypass valve to continue to allow oil to pass through if the filter becomes blocked. And that is highly unlikely with the excessively regular oil changes we give them!
Mike.

[wilf]

I think you might be surprised by just how much oil, clean or otherwise, bypasses the filter via that internal bypass valve. Most especially when the oil is cold. They are not really "full flow" filters by any means.

[GTJones]

Hi Mike

Thanks for the information, managed to get a filter that you suggested and it now has no significant pressure drop on idle? Really strange although the only thing i can see is that the filter i fitted is about half the height of the original Crosland 2022 and the VFL117 you suggested.

Gary

[wilf]

I can't see that that is an improvement. The filter area is important. If you fit a much smaller filter you are automatically reducing the actual area of the filtering medium, and so increasing the chances of the bypass valve opening.

[Lingen]

Gary. Problem solved then by the sound of it. I went for a larger filter size over the original one when I fitted my adaptor many years ago. It seemed sensible to me to increase the area of filtration as it was so easy to do so with the range of spin-on filters readily available.
Mike.

[Staggard]

Got me thinking, so I have been trolling through U tube watching different filters being taken apart, I never realized that there was so much difference in quality and operation ( never finished learning) It would seem that Fram came out as being poor quality and most likely to re introduce crud back in to the engine via the bypass valve where as the Motorcraft filter came out with good results in construction and bypass valve design. So that's what is going on when I get the car back from the painters. I just Googled oil filter bypass valve.