Why do they put oil filters upside down? I know yanmar does and now Perkins! You Tell me to fill the filter with oil before fitting? How many seconds do I have before the oil gets to the bilge? It's a mission!
southace,
setting aside Bruski's amusing little prejudice about engineers and responding to your question.
i think that you are saying that you are filling the filter with oil, then trying to fit to the engine. If this is the case, why? If that is a recommendation in the manual then possibly this was relevant for another engine with the filter spun on from below?
I have only ever given the filter a light coating of oil, then spun on. Then fill the engine. When you run the engine the level with drop a bit so top up to the correct level. I assume this is what others do?
Treat it like any other oil filter. Smear some oil on the seal and install. When you flash up the engine the oil pick up will be submerged in the sump oil and the oil circulates immediately. The bearing surfaces will still be oil covered anyway.
To remove this sort of filter a large plastic bag fitted over during the last couple of turns and let the filter drop into it will same a mess.
Our Yanmar has the oil filter horizontal. Nothing in the manual about filling the filter before installing. Get a small amount of spill when removing old filter and then do exactly as per what LMY says, fill up, run for 10mins, check for leaks and top up.
Select to expand quoteRamona said..
Treat it like any other oil filter. Smear some oil on the seal and install. When you flash up the engine the oil pick up will be submerged in the sump oil and the oil circulates immediately. The bearing surfaces will still be oil covered anyway.
To remove this sort of filter a large plastic bag fitted over during the last couple of turns and let the filter drop into it will same a mess.
Like Ramona said, fit it normally . I never fill a filter with oil or fuel.
Some motors I spin over with the fuel shut off until I get oil pressure, then start it. If you do this in a boat be mindful that you are filling the exhaust with raw water. Always watch your oil pressure as you start especially if you have just serviced the engine.
If you have an inverted oil filter, and oil pressure seems to take for ever to rise/pick up each time you start, it may be worth checking to see whether the filter you are using has an anti drain back valve. Some brands of filters don't have them even though they are compatible.
An anti drain back valve stops oil draining out of the filter and back to the sump each time you stop the engine
Sorry but I'm just going by the recommendations from Perkins , Thornycroft , BMW marine , Holden and Ford for fuel and Oil always have and always wil. :)l
Select to expand quotesouthace said..
Why do they put oil filters upside down? I know yanmar does and now Perkins! You Tell me to fill the filter with oil before fitting? How many seconds do I have before the oil gets to the bilge? It's a mission!
I was speaking to the question, as the question was "Why do they put oil filters on upside down?" and it's not a prejudice, it's just the plain unvarnished truth, ask any mechanic, don't bother asking an engineer though they'll just start talking about how function decides where things go and how they're put there. I will give them the benefit of the doubt and admit they might be doing it subconsciously, after all they really don't like thinking about others touching their baby. 
that is interesting.
See page 113 of the attached, random selectionn of a manual from the Perkins website. This recommends against the practice due to risk of contamination. (I checked one other manual, this statement was not there, but there was no recommendition to pre fill either)
s7d2.scene7.com/is/content/Caterpillar/C10337324
I must admit though, I cannot see the differeence in contamination risk from adding fresh oil to the filter, or pouring it into the rocker cover?
I have way to much spare time, should go and do something usefull like polish the main halyard!
Select to expand quoteLMY said..
I must admit though, I cannot see the differeence in contamination risk from adding fresh oil to the filter, or pouring it into the rocker cover?
The risk is that you may put foreign material directly into the engine oil gallery because you have bypassed the filter by pre filling it (anything could be in an oil container). By pouring oil into the normal engine fill or rocker cover, a foreign object will most likely stop at the oil pick up screen in the sump and if it gets passed that the filter should stop it.
Blocking the oil gallery of an engine usually equals catastrophic failure
Anyway the oil.Change went well even if I did put some pumps into the filter from the 20 litre drum, no rattles when I fired her up. The fuel filters was a different story.
I filled The primary filter with fresh diesel as the filter box and mechanic advised. Started and she ran sweet. Tryed my hardest to fill the split filter with fresh diesel but once I done it up and fired again ended up with air in the system,
bleed and ran good for 2 minutes but got more air! Changed small o-ring on bleed screw and put washer inline. Still drama!
Changed the filter with the 2nd Perkins spare....still same drama, got a cross referenced filter from local mechanic bleed motor now starting first pot but now timing chain sounds rattley! Grrrrrr. Will get new VDO hours tomorrow and wire to ignition apparently perkins VDO hours fails around 1250 hours!
i love boats!
Remember Southace, A day working hard on your boat is still better than a hard day working at the office. 
seriously though the jobs you finish are all worthwhile once you are again out on the water enjoying the world as you sail past.
I have always added fuel or oil to filters before installing and then always check and top up after starting the engine.
On my boat, both the oil and primary fuel filters have been relocated to a bar attached to the front engine bearers and are very easy to get at. It also has a small external oil pump that activates when the ignition is turned on that pumps oil until it reaches 8psi so that you are never starting a dry engine.
I will try and get a pic and post it if I can work out how to do it.
