Oil filters - by-pass relief valves

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MajorF

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Trying to get my head around the function of by-pass relief valves that are incorporated into oil filters. Is it correct that VP filters have by-pass relief valves set at 16.5 PSI? What would happen if you installed a non-OEM oil filter with a by-pass relief valve set at 8 PSI?
 
The by pass valves are to let oil though in the event of a blocked filter and thus stopping starvation of oil to your engine. Manufacturers will have individual specific valve settings.
I suspect that some non OEM manufacturers use the same valve for all applications or maybe non at all.
 
Also, to complicate things, some oil filters have a non-flow back facility to prevent the oil filter emptying when the engine is not in use, if it is mounted horizontally, or upside dow.. This helps prevent a bit of oil starvation on start-up. Some filter manufacturers are less good at providing this.
In car engines ,owners' clubs usually have recommendations which filters are the best.

Don't know about marine engines .....
 
Have used various branded filters over the years, most with names you will have heard of, usually from my local motorfactor.
Never had any problems .
Never tried Volvo Penta , but some folks are very keen on them.
 
oldgit said:
Have used various branded filters over the years, most with names you will have heard of, usually from my local motorfactor.
Never had any problems .
Never tried Volvo Penta , but some folks are very keen on them.
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I have never had any problems either and have been using alternative filters and oils approaching 500 hours on my present boat and also used them on my previous boat.

As a matter of interest the 'Volvo' part number is exactly the same as the 'Volvo Penta' part number (at least it is for the oil filter for my boat). I have little doubt the Volvo car part costs less although I cant say I have explored that option.

I doubt Volvo or Volvo Penta have their own filter factory. The Mann filter I posted above seems a closer match than the Baldwin filters I have used in previous years. However I know Baldwin must be a good brand as they were used by a well respected engineer known to this forum.

One thing to watch when selecting spin on filters is the threads must of course match . In my case imperial thread .
.
 
MajorF said:
Trying to get my head around the function of by-pass relief valves that are incorporated into oil filters. Is it correct that VP filters have by-pass relief valves set at 16.5 PSI? What would happen if you installed a non-OEM oil filter with a by-pass relief valve set at 8 PSI?
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Are all the modern VP engines still using the metal spin on oil filters, or have they moved onto paper only like most vehicles?
 
The VP oil filters for my KAD44s are 423135. I purchased these from in-line filters FIN-FL70548 FILTER (8PSI) as it states on their website that they are the equivalent of VP423135 and they can be applied to KAD44 engines. In another forum they caution against the use of non-OEM because of the differences in pressure of the by-pass relief valves. It's the implications (if any) of those pressure differences that I don't understand. I know that MANN filters are a good brand and I have cross referenced 423135 on their website MANN-FILTER Online Catalog Europe and their comparable filter is W950/13. The pressure setting is 1.20 bar which equates to 17.4 PSI and is much closer to the alleged setting on the VP filter. I will be speaking to in-line filters today to determine what the differences in pressure actually mean; hopefully not much.
 
MajorF said:
In another forum they caution against the use of non-OEM because of the differences in pressure of the by-pass relief valves
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Clocked up 1500 hours or so with previous boats over last decade , all maintained with aftermarket alternative filters.
Around 90 boats on our club moorings , yet to hear of any story about engine failure/damage connected with oil pressure .
The vast majority self maintain , aware of only one skipper refusing to use anything other than VP filters and replacement parts.
Usually its old age and neglect that causes problems.
Numero Uno grief .....................Impellor failure.
It would help if you could actually physically get to the pump.
Chums Princess 360 is an absolute nightmare.
 
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I for one will vouch for Mann filters - excellent quality.

I've never got a clear answer as to who manufactures filters for Volvo Penta, but it will be another big filter specialist like Mann. The cost saving is considerable and the build quality appears excellent.

Same with oil - many of us in the know are now using Shell Rimula or similar. I paid £64 per 20l recently whereas Volvo oil (again, Volvo don't make it themselves) was £120 for the same. Helix (and many others) are approved by Volvo Penta (VDS-3 in my case). I've been using Shell Helix and Mann filters in my Range Rover for quite some time without any issues (in fact, the oil always comes out cleaner than it used to). We won't talk about my last car which decided to implode and put a con rod through the block, but I'm going to blame Land Rover parts and servicing (and design, and manufacture....) for that one!
 
oldgit said:
Clocked up 1500 hours or so with previous boats over last decade , all maintained with aftermarket alternative filters.
Around 90 boats on our club moorings , yet to hear of any story about engine failure/damage connected with oil pressure .
The vast majority self maintain , aware of only one skipper refusing to use anything other than VP filters and replacement parts.
Usually its old age and neglect that causes problems.
Numero Uno grief .....................Impellor failure.
It would help if you could actually physically get to the pump.
Chums Princess 360 is an absolute nightmare.
Click to expand...
With 63ps ?
 
Taken from another forum. May add something to the debate:
Every engine manufacturer knows their tolerances in their engine. It will be clear, that the contamination in the lubrication oil must be controlled and kept on a low level. It is highly comprehensive and time consuming laboratory work to define the quality of a filter. The engine manufacturer will have chosen and tested his applied filter(s) which is best suitable for his engines. He has also to guarantee his engines and therefore also the applied filter is an important component of his engine. A good filter has many characteristics as: suitable for the designed oil flow, large flooded wet surface, high percentage of filtered particles at a certain size - most particles at 4 - 6 - 15 micron-, various filter-layers, a small pressure drop over the filter and a long life time. Also the viscosity of the lubrication oil fluid and the fluid himself, is playing an important role. Last but not least: also the quality of assembly and glueing of the filter material in the housing must be 100 % with a controlled quality assurance.
Therefore it is far from suitable to choose a filter on the mounting parameters as mounting thread and mechanical sizes and cost. So therefore do not try to save a couple of dollars on the filter. You just do not know what you are buying if only looking at cost and dimensions.
Concerning a bypass check valve: normally this valve is not integrated in the filter itself. Also a bypass valve must be of good quality, because it may happen, that in case of high viscosity (low oil temperatures and high engine speed, resulting in higher pressure drops over filter material and housing) the bypass check valve may open and not correctly close and stay open partially. In this case you are not filtering at all with all consequences. Normally the cracking pressure (point of opening) is not important, because it may open incidentally. A bypass valve to open when the filter is clogged too much may not happen and the filter should be replaced before clogging.
I' writing this as an independent hydraulics engineer.
 
SEARANGER ANCASTER said:
the bypass reliefs are normally in the filter head , not in the element
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with great respect to you this is not correct!!!

it was my job some years ago to test lub oil filters and the fact is "some" spin on filters DO have internal valves fitted to the end plate of the filter element inside the filter can. these valves have a calibrated spring which will allow opening from below to 10 psi up to about 20psi ......dependant what the engine manufacture wanted.

The purpose of the valve as had been said already is to open at the pre set value as a fail safe against element blockage or possibly open on a very cold start where oil becomes thicker and higher pressures come into play.

if you fitted a filter with lower rated valve then you are lowering the length of life your filter element will have.

If no valve inside the filter then there is usually a valve in the cast filter head. I imagine the valve in the filter will suffer less fatigue than the one in the filter head which will be the same age as the engine and hence after many openings spring fatigue may take place. The bad news about the valve opening inside the filter is that oil flow passing tangentially across the dirty side of the pleated element may carry particles/debris off the pleats though into the engine so valve opening is completely undesirable.

Typical mean filtration value for lubricating oil filters is 30 microns no finer. In post above I can assure you there is never 100% quality assurance!!! usually checks are 1 in 1000 by random sampling or even greater once production is in motion, Because in our factory we completed 1 filter per second night and day.
 
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Just to make things more complicated where the filter is fitted upside down, there is sometimes a rubber flap valve fitted to prevent oil drain down when the engine is at rest.
It was my task to develop a 1 piece flap that was spring loaded so that this flap acted as a one piece anti drain down and element relief valve thus saving some components and hence cost of manufacture.
 
The intent was that the valve is a fail safe. filters that were intended to last 10,000 miles would have a factor of safety of at least 3 times say 30000 miles duty before the differential pressure across the filter would open the valve , we proved this on test rigs where the filters were artificially clogged with a mixture of soot, red iron oxide powder and calibrated dust from the Arizona desert. And then on the road by driving cars at 1000 miles per day for 30 days not a great representation of actual service life but it satisfied the motor companies who at the time wanted to extend service intervals!! .
 
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