XHVI, I've been reading your replies and I think I might be able to help you understand. If I am correct, you are thinking the purpose of an anti-drainback valve is to keep oil from coming out of the FILTER... Yes, it should, and seeing that our filters are mounted right side up so it is always filled with oil, the next thing is keeping the oil galleys which are ABOVE the filter full. If you don't have an antidrainback valve, the oil in the gallies that are ABOVE the filter will drain back into the filter... The antidrainback valve in our case will help keep the oil that is above the filter from seeking to the lowest point. This helps out a little bit by giving the oil a headstart to the upper part of the engine. I hope this helps.
Here's the truth about the difference between the AC PF 58 and PF 59
- Thread starter Alex D
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Thank you.
I always knew that the purpose was to keep oil IN the filter, it just wasn't until a few days ago that I learned from Patman that in my case, an antidrainback is useful even if my filter is mounted upright. Interesting information... I'm glad I have only used a non antidrainback filter on my car a few times.
In the modern transverse mounted 4 cylinder Frontwheel drive with the filter mounted horizontaly the purpose of the valve is to keep the oil IN the filter and not drain by gravity to the oil pan creating a dry start in terms of refilling the filter.
With the oil pump pick-up tube submerged the amount of oil from where the filter is placed through the oil galley to the tube cannot overcome by volume or weight and drain that way,if oil is lost at all it MUST come from out of the filter.
In days past it was a huge problem for the Toyota 18R's,8RC's, 2 and 3 TC's with hydraulicly tensioned timing chains. The only filters available at the time with ADV's were Toyota OEM and then later Purolator,,those carbed motors would allow for dry starts "filter was dry",later Toyota devised a means to not allow ignition to fire until oil pressure was sensed. Todays motors with modern Fuel injection will not allow a motor to start with out oil pressure. A absolute vertical mounted oil filter like a old small block Chevy uses has no need for a ADV,the weight of the oil up high cannot over come the volume of oil in the filter and push it out.If you hear noise on start with one of these motors the lifters has blead down,not the oil filter has drained
Hope this helps
With the oil pump pick-up tube submerged the amount of oil from where the filter is placed through the oil galley to the tube cannot overcome by volume or weight and drain that way,if oil is lost at all it MUST come from out of the filter.
In days past it was a huge problem for the Toyota 18R's,8RC's, 2 and 3 TC's with hydraulicly tensioned timing chains. The only filters available at the time with ADV's were Toyota OEM and then later Purolator,,those carbed motors would allow for dry starts "filter was dry",later Toyota devised a means to not allow ignition to fire until oil pressure was sensed. Todays motors with modern Fuel injection will not allow a motor to start with out oil pressure. A absolute vertical mounted oil filter like a old small block Chevy uses has no need for a ADV,the weight of the oil up high cannot over come the volume of oil in the filter and push it out.If you hear noise on start with one of these motors the lifters has blead down,not the oil filter has drained
Hope this helps
Here is a for instance. Back in the early 90's a lot of Chevy small block engines used the PF35 oil filter. This filter DIDNOT have a ADV. then during the time mentioned above Chevrolet had some problems with this filter and engine on cold starts knocking, clicking, or ticking. Their solution was the PF1218 filter for these applications to stop the noises. The only difference between the PF35 and the PF1218 was the anti-drainback valve that was installed in the PF1218. So I assume from this that it is possible for oil to drain back from the upper parts of the engine through the filter and back to the pan.
I would have to agree that it is unlikely that all the oil in a filter will drain out into the oil pan during engine shut down.
Over the years there have been many, many instances where for some reason or another a vehicle is being operated with no oil! Burns it, leaks it or maybe it was never installed. However, the oil filter is never empty on these cars when it is removed, so that doesn't support the siphoning theory for me. This is only an opinion though, no actual facts to refer to.
Over the years there have been many, many instances where for some reason or another a vehicle is being operated with no oil! Burns it, leaks it or maybe it was never installed. However, the oil filter is never empty on these cars when it is removed, so that doesn't support the siphoning theory for me. This is only an opinion though, no actual facts to refer to.
Triple_Se7en
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Wow, this thread is old. Was hoping the PF59 had a silicone ADBV. But it doesn't. Neither does the sister PF61, which I once used for 10 years and it's minus any ADBV.
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