Oil Filters - Drain back valve

Depends on the particular engine, that is how the filter is positioned. If it's put upwards, or in such a place that oil will drain off from it, then on starting the engine oil has to fill the filter first, and engine is not lubricated until it happens. So on every start engine is wearing down with no lubricant provided for a while.
Better to check what kind of filter should be used in your engine.
 
Rossynant said:
Depends on the particular engine, that is how the filter is positioned. If it's put upwards, or in such a place that oil will drain off from it, then on starting the engine oil has to fill the filter first, and engine is not lubricated until it happens. So on every start engine is wearing down with no lubricant provided for a while.
Better to check what kind of filter should be used in your engine.
Click to expand...

Thanks for the response.

Will try and find out as suggested.

The engine maker's filter is around £11 and I have purchased a cross referenced alternative at £4.25 (skinflint). I would not have even thought about it had the chap at the accessory shop not mentioned that it did not have a valve. Perhaps the engine maker's one doesn't either.
 
What make of filter have you bought and how did you select the equivalent, what's the original?
Most of the manufacturers websites e.g. Fram, Mann, give you equivalent tables with full details of whether the filter has a non-drain valve and equally important a bypass valve.
www.inlinefilters.co.uk is also very helpful e.g. here is a Fram equivalent for Volvo 2020 filter
http://www.inlinefilters.co.uk/?key...dvanced_search_result&search_in_description=1
and you can see that contrary to scare stories it has both.
 
If there is an option of one with a valve I'd go for that. Sometimes different installations and states of tune have/don't have a valve. On my Imp engine there isn't a valve. I could fit a filter mounting block which has an integral valve, except there isn't room.
In my case the engine has a 10.5:1 compression ratio so I spin it over on the starter and build the oil pressure before pulling the choke on and letting it fire.
Modern oils should leave a film on bearing surfaces to protect them, but you still can't beat some oil-flow.

Lots of marine engines use low spec oils and are left dormant for long periods. Any help in the form of a valve would be welcome, in my opinion.
 
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Interesting thread, having just serviced my perkins 4108 with a bunch of filters from the motorfactors. I was pleased at £22 for a gallon of oil, and oil filter and 2 fuel filters, but now im curious:

all the elements I fitted this year are 'mann filters'. just checked their website and the filter I fitted W940/1 does appear to have a drain back valve (at least thats how I read the table drainback valve column has a 1 in it):

https://www.mann-hummel.com/mf_prod...sFrNoList=W9401&ktlg_subpage=0&gobackToPage=3

so hopefully okay on that front (my filter is upright on top of the engine) but when comparing the filter spec to the original (fram ph2821a) it seems the filter I fitted has a bypass valve opening pressure of 1.2 bar. where as the original fram one should be either 0.7 or 1 bar. what the heck is the bypass valve? pressure? and am I going to damage something.

the problem is, going on the mann catalogue. entering fram ph2821a it suggests a slightly different model filter to the one the motor shop gave me. Its my fault. last year I took the fram model number to the motor factors. they gave me a motaquip equivalent. this year I took the motaquip filter number to the same shop expecting another motaquip, but they have changed suppliers to mann, so they gave me a mann equivalent to the motaquip. Sort of an oil filter game of chinese whispers but I seem to have drifted from the original spec. I have learned my lesson for next year but would rather not make the mess of changing the new one as long as this bypass pressure business wont hurt. If I understood what the valve was for it would help...

help!!!
 
If you have thick cold oil and/or a clogged filter (not that you ever would, would you!) the bypass valve opens to let unfiltered oil through so the engine does not die for lack of it.
I would not personally think that .7, 1 or 1.2 Bar mattered as long as you have one.
However if you want to keep to the .7 Bar it's the W940/24.
 
You better keep that Perkins with over 1.2 bar pressure anyway ;)
Was this original set-up on your engine, or adapter? I'm looking for adapters to change from old kind "element changing" filter but space is tight down below. Upright filter sounds nice.
 
I think its original... but have only had this boat for 2 seasons. its certainly dead easy to spin the element on and off and with the built in sump pump it couldnt be easier to change. I heard that because my varient of 4108 is raw water cooled, the thermostat is set cold so the salt doesnt clog the internals. The downside of this is not only enhanced engine wear by running at cooler temperatures but a tendancy for the oil to sludge. Its probably worth a mid season oil change since its so simple.

Re: the bypass valve, so if I understand that is there incase the filter gets blocked so the engine wont be starved of oil. As stated 0.7, 1 or 1.2 bar should not make too much difference then. she hits 60-70 Psi within a second or too of starting. Next year I'll get the right one!!
 
Thanks, I'll look into later engines. Not sure what adapters will fit in my bilges, so good to know there is upward filter possible.
I would not worry much about raw water cooled engine - not so much difference. Indirect cooled have thermostats set for 70 (with calorifiers) or 80 C; actually the 80 C one opens at 75.
Guess direct cooled works just below 70.
 
Thanks but no thanks. ;) There is extra 2-3 liter of oil already in marine Perkins. Mileage of exterior oil pipes at this engine is something to be admired... and two oil coolers to leak...
Just thinking about mine - bending over down to dismantle that bowl kind filter seems bit unnecessary, and I plan to put some fuel filters about this place, but would be then even more inconvenient to reach.
 
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Troubadour said:
What make of filter have you bought and how did you select the equivalent, what's the original?
Most of the manufacturers websites e.g. Fram, Mann, give you equivalent tables with full details of whether the filter has a non-drain valve and equally important a bypass valve.
www.inlinefilters.co.uk is also very helpful e.g. here is a Fram equivalent for Volvo 2020 filter
http://www.inlinefilters.co.uk/?key...dvanced_search_result&search_in_description=1
and you can see that contrary to scare stories it has both.
Click to expand...

Thanks for the info and the Link. Very helpful.

The problem has now been rectified by the accessory shop. I gave a Fram part number for a Volvo filter that was then changed again by the shop to an UFI filter which was an incorrect match.

Probably, like Lakesailor, I am happier with the ADB Valve to stop the filter draining. The filter on the block is not oriented north and south . Also, with the marine infrequent use compared to a car, nice to know that the oil is going to get where needed as quickly as possible.

As an aside, while looking for various part numbers, You Tube, flagged up various oil filters with the innards being sawn off and inspected with comparisons being made. Have to say that I will be steering away from the cheaper end of the market in future.
 
Don't get too carried away with the ADBVv, this is simply a flimsy rubber flap covering the inlet ports into the filter. If the engine is idle for a long period the oil will seep past and back into the sump.

In the grand scheme of things we don't start marine engines that often, so as long as you allow oil pressure to build up at gentle revs, the engine will be fine. Having an ADBVv will reduce wear for the stop starts over a few days of continuous use.

If your filter sits with the entry upward then an ADBVv is pointless, but makers such as VP use the same filter on many engines.

The bypass pressure should be less than the difference between actual pressure and minimum pressure recommended in the makers manual. Most are set around 1 - 2 bar. As most owners change their filters with less than 100 hours each year the likelihood is the bypass will never operate as the filter simply won't be that dirty.
 
LONG_KEELER said:
As an aside, while looking for various part numbers, You Tube, flagged up various oil filters with the innards being sawn off and inspected with comparisons being made. Have to say that I will be steering away from the cheaper end of the market in future.
Click to expand...

The US enthusiast market on YouTube seems absolutely venomous about Fram in particular, and talks about them being much cheaper than others, like $3 or so.
As far as I can find there is no connection between Fram USA http://www.uci-fram.com/ and Fram Europe http://www.fram-europe.com/en/about-fram/the-original-performance.html

Rather like Exide Batteries - the name belongs to different unconnected companies in different areas. I don't know who had the Fram name originally.

Usually when I buy a filter I don't get a choice of make, it's whatever the factor has in stock, that's often the case with mail order too, but I've used many Fram over the years (as well as Mann, Crosland, Unipart, Baldwin, Blueprint and others) and never (knowingly!) had a problem. On replacement elements as opposed to spin-ons, the quality and construction seem to be the same and price is much of a muchness, I haven't opened up any spin-ons to look.

So which ones do you think are "cheaper end of the market" to avoid? If you buy a non-original one from Keypart you pay less than for the Volvo (or whatever) branded one but a lot more than from a motor factor and you don't know what make you are getting! e.g. http://www.keypart.com/volvo-penta/diesel-engine/2002/19831991 original £15, Keypart brand unspecified £11.65, my local factor about £5.50, http://inlinefilters.co.uk/index.php?main_page=product_info&cPath=935_938_942&products_id=13792 at £2.82 and not clear what make you will get.

So I honestly don't know how you would choose or guarantee quality - do you?
 
Troubadour said:
So I honestly don't know how you would choose or guarantee quality - do you?
Click to expand...
By knowing the real make and type. Here about I ask my neighbor, car service owner.
Some years back there was factory making filters here in Poland. Originally part of Aviation production company, they knew how to keep quality. Almost every european company bought from them; some were made to ordered design but most were standard. They only changed the print on box. Now they are making less, cheaper sources have taken the market. But I was always using those. http://www.wf-filter.pl/
Then there were the rest, smaller makers. Some lower quality (some Romanian ones, or just china or such) and not necessary cheap - seller sets price; or a best ones, for those who knew.

Lately I was given a Romanian filter (fuel for Volvo car) as Romanians got quite good. The same I would have from Volvo dealer, 10 x more you know, and most other brands.
But can't tell you who makes UK brands... :o
 
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