Vokes Oil Filters UPDATE

[3.8Jaguar]

We are looking at manufacturing a small quantity of replacement elements for the Vokes oil filter housings.
   
   It would be of great help if we had some feedback from members as to how interesting this would be for them.
   
   Application:   Fuel
   
   Sample sent:   Yes
   
   Height:   120mm over gaskets
   
   Top cap:   3 segment laser cut plate spot welded to open cap, 66mm OD – SK508
   
   Bottom cap:   Closed cap 66mm OD x with 11mm bolt hole
   
   Inner cylinder:   10mm solid tube
   
   Outer cylinder:   3mm hole galv perf
   
   Media:   Needle felt supported with galv mesh backing
   
   No. of pleats:   16
   
   Depth of pleat:   10mm
   
   Adhesive in caps:   PU
   
   Gaskets:   3mm thick neoprene segmented on open cap
   
   Packing:   Bulk boxed
   
   Extra details:   We would be unable to offer the "ears" on top plate
   
   Price based in production of 25 units  £45.50 inc VAT ex P&P.
   
   
   
   Due to the Price this may not be a goer, however it depends on quantity of order.
   
   I have only put a negligible  margin on to cover our costs.
   
   
   
   
   james@bristolengineering.co.uk
   
   www.bristolengineering.co.uk

[B.P.Bird]

James has a brilliant project here, for all kinds of reasons:
   1) Originality - first off it is a real shame to look under the bonnet of a Bristol engined A.C. and see that the works 'dog's bone' is missing along with the Bristol Vokes mount and cannister. Secondly it follows that the oil cooler pipes are no longer connected in the designed way.
   2)Now here's something which should put the cat amongst the pigeons - replacing the original Vokes set up means accepting a low performance option. If you have been believing that your modern 'spin on filter' is an improvement on what Bristol and Vokes gave us you are maybe wrong. A short Google expedition will shew you what a minefield Oil Filters are. A good place to start is: http://minimopar.knizefamily.net/oilfilters/reference.html#delco
   Then just follow the links. The real shock I got was that brands I had always thought of as high quality are now contracted out and are just badge engineering. In fact some famous brands may be identical under the labels. Would anyone care to bet on them not being Chinese?
   3)One other loss is the aeroengine style shuttle valve which should be part of the filter mount when an oil cooler is installed. This protects the engine if the oil cooler has too low a flow rate, for example cold oil or debris from the collapsed paper element hidden in your spin on cannister....
   All in all I think James is doing us a great service and should we not get some support going? At the moment the contrast with the Ceandess petrol filler cap project is a bit depressing - out of sight out of mind? If you still have the Vokes plumbing, preserved from the day when you went spin on then this could be the moment to put things right. What do you think chaps?

[Robin A Woolmer]

Interesting Comparison with significant variations in surface area of the filter element but nothing about the level of filteration in microns!
   I use a 15 micron filter full flow to filter to a greater degree one must also use a by-pass filter.
   Where is the Pressure relief valve in the oil path? is it after the filter?
   
   Robin

[AC Ace Bristol]

A good project, usefull to many members in USA, Europe & UK.
   
   This subject has raised it's head many times over the years.
   
   please refer to:-
     "AC Exchange" Fall 1996 vol 15.
   New Products
   
   Bristol Oil Filter Adaptors:
   
   Vokes Oil filter elements have always been expensive even though we (a supplier in England and I (Ron Leonard)) have combined our orders tomake them as large as possible.
   Each time we are faced with price increase, this time we are not to reorder.
   
   There will soon be an Adaptor that will fit on the underside of the Vokes Filter Head to accept a common Spin on Filter. The advantages are numerous:
   
   Oil cooler can still be utalized.
   
   Looks original (remains in vertical position).
   
   Minutes to convert with no modifications. cheap spin on filters.
   
   Plus all important... The oil flows through in the correct direction.
   
   
   AC Exchange  Summer 1997 Ron Leonard.
   
   Bristol Oil Filter Adaptor.
   
   This is the FIRST Adaptor designed to run the Oil through a Spin on Filter in the RIGHT direction.
   The original VOKES elements were designed specifically for Bristol's ODD oil flow design.  The oil flows from the Center of the filter to the outside in the Vokes unit,
   utalizing a much smaller filtering surface than other automotive applications.
   The others flow inwards from outside, taking advantage of much more surface.
   
   Please refer to Oil Flow chart in Owners Manual..[;)]
   
   Adaptors used up to now (1997) were simple to machine compared to these. However they don't invert the flow of oil to match the Design of the Spin on Filters used.
   
   Well known restorer Mike Dapudja decided to do something about this problem while he was rebuilding a Bristol engine.
   The Adaptor comes with instructions and a Fram HP-1 filter which has a maximun recommended working pressure of 200PSI and abusrt pressure of 500PSI.
   It can be installed in about the same time as a normal oil filter change and the cooling fittings are not affected....
   
   For those in England and Europe adaptors will be available soon Summer 1997...... via  Brian Eacott. [;)].
   
   I have run BEX333 with one of these adaptors for at least 48/49,000 miles without any problem. (Fitted by previous owner- Lee Kolb in 1997)
   
   Visually looking into the engine bay every thing looks standard bar the glimpse of the orange oil filter alongside the battery.
   I will take a picture and try to get it posted.
   
   The Standard Oil Cooler take off works as Bristol designed, As the oil temperature rises the  Vokes built in  spring release / valve   diverts oil through  the oil  cooler.
   Again please refer to the picture in the Workshop manual...( I will try to post picture, If only it was straight forward)
   
   Not sure if these Adaptors are still available or if Ron Leonard could get a new Batch made.[?]  maybe someone in USA can discuss with Ron Leonard before he retires.
   (Ron lives in Durango, CO81301)
   
   Fram HP-1 oil Filter approx £7.50 each or the shorter by 1.5 inch   MOP P4452890 Filter @£8.00 each plus vat.
   Max flow rate .. 10 gpm ..[;)]
   
   Just an idea, Open to discussion.. ...However for those who must retain originality, a batch of original design elements must be commissioned.
   
   Have Bristol Owners Club commissioned same or are they prepared to contribute[?][?]
   
   Keith   ..[:)]

[B.P.Bird]

We need to hear from James what level of filtration is proposed from the chosen medium. I suppose his supplier will have alternatives to suggest. My preferred spin on, for the Ford 260/289, filters down to 10 or 12 microns, but for racing the supplier, Wix, produces a competition high flow filter which only filters down to 45 microns. Horses for courses I suppose. To answer Robin's question: On the Bristol engine the adjustable Pressure Relief Valve comes immediately after the pump. With an oil cooler correctly installed the shuttle valve comes next. The filter bypass is integral with the oil filter housing and The Insert Assembly (this last is the part James is proposing to replicate) it is a simple and elegant solution which can be proved to function correctly with each filter change - unlike the horror stories reported when some spin on filters are opened up. The Oil Flow chart referred to is on Page 26 and 27 of A.C. Cars Ltd. 'Workshop Manual Bristol 2 Litre Engine' and is reproduced in The General Instructions  for both the Ace/Aceca Bristol and the Greyhound.
   I remember the proposals to adapt a spin on in the 'correct' vertical position, as described by Ron Leonard. This would be a much better solution than the horizontal 'sandwich' plate system commonly seen nowadays. As well as correctly plumbing both the flow direction and the oil cooler ports, the vertical solution will also retain the A.C. Oil Filter Extension (the Dog's Bone)  therefore the Oil Temperature Gauge Bulb will remain in the correct place. I have yet to come across anyone using Ron's system - did it ever get off the ground?
   However one problem this system will not help is the problematic quality of a spin on cannister. There is so much evidence of low performing and inadequate surface area of filter medium plus the medium not being properly glued in place and thereby being bypassed by unfiltered oil, together with non-functioning bypass valves and, perhaps worse, weak or permanently open bypass valves. I stopped using AC Delco when I found they were changing production to an outside supplier and switched to Wix. Having said that it is a matter of trust with all spin on filters - you cannot see what is inside until its too late.
   Incidentally, like many changes Bristol made to the BMW engine, the 'reverse' flow filter was common aero engine practice to prevent a filter being squashed by high oil flow rates - especially with cold oil and eager pilots.....

[nikbj68]

Here are scans & photos to accompany Keith`s posting:
   
   
   
   
   
   
   
   
   

[AC Ace Bristol]

Nik
   
   Thank you for posting the photos and my scans, sorry for poor quality but used my blackberry.[:(]  Hopefully enough detail for evaluation and open discussion. (emailed copies to Barrie)
   
   The Fram  HP1 spin on Filter is very close to the Battery, and is easier to change by lifting off the Vokes Head and then removing the filter unit.
   
   I haven't seen or heard of others using this adaptor, but believe two batches were produced in 1997/98.
   
   Maybe someone can contact Ron Leonard and ask if it is viable to manufacture another batch.[;)]
   
   Cheers
   
   Keith..[:)]

[Robin A Woolmer]

Conversion adapter plates to use spin on filters are supplied by  'Think Automotive'  i am not sure if they do one for the Bristol engine but they do many car types, worth a contact, ' www.thinkauto.com ' 02088475338

[3.8Jaguar]

Thank you all very much for your great and valid input.
   I am awaiting conformation on the filtration as it the proposed medium has been altered from my first discussions but the target filtration given is 15 Microns.
   We still supply spin on adaptors for the Bristol engines, both block mounted and filter head mounted.
   This project is purely in response to those owners who have expressed an interest in the original Vokes set up and we appreciate that other owners will prefer spin on conversions.
   
   Again many thanks to every one who has given feed back it is all valuable info.
   
   Regards
   
   James
   
   www.bristolengineering.co.uk

[BEX 288]

I would be interested in purchasing the original Vokes set up. Cheers Stephan

[3.8Jaguar]

Dear Stephan
   
   Please contact us directly, contact details can be found on www.bristolengineering.co.uk
   We still need a few more positive enquiries to proceed so all interested please contact us with quantities needed.
   
   Many thanks
   
   James Harris

[B.P.Bird]

Just in the middle of some work on LM5000 due to further damage from ethanol fuel, more of which elsewhere, I got to the oil change and saw that I had forgotten that my Vokes oil filter housing still has its original transfer in place. It makes interesting reading:
   ' The Amber Cross - Symbol of complete engine protection ' There is then a short narrative, headed 'Lubricating  Oil? / And? Filtering' which goes on to say, 'Cleaning and Servicing. Dismantle filter and and clean thoroughly in petrol or other suitable solvent. Allow to dry and reassemble. Renew joint rings if damaged. Renew filter element periodically. See handbook for full servicing instructions.'
   On the basis that you can wash and reuse the Vokes filter several times it becomes a much more economic proposition, assuming that James is going to use a similar washable filter medium.
   In any event this is a practice I have used on various Bristol engines over the years without any problems. It would be a bonus if the handbook referred to turned up....