Is there a difference between an engine oil filter and an Allison trans spin on filter? Case in point, when I went to the Wix filter site and typed in HP1, the Fram hi-performance filter, one of the avail filters down the list is Wix 51622, which is the Allison trans filter. Also on the Purolator site, pureone.com, and put in HP1, it lists the L39001 filter. The application is for a VW air-cooled engine which has been modified for a full-flow oil filter. For decades one particular shop in So Cal has sold the Fram HP1, stating the use of the standard Fram PH8A could burst as the filter is installed before the oil pressure relief valve, which is there to protect the cooler.
Difference between filters ?
- Thread starter VWguy
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That doesn't quite make sense. Without some really obscure process/mechanism, the relief limit is the relief limit. On hydraulic systems the OEM may filter the high pressure side to protect the pump to some critical level, but we're talking some pretty intense pressures. Most are installed on the low/no pressure return lines.
This would have to be some radically hi-per setup for this to happen, imo. It can surely happen with some engine that goes from 1500-7500rpm in a few seconds. The can will be the weak link and your relief port on the pump can be overwhelmed ..and there is surely some inertia/time/physics thing that could/would come into play ..but I'd find it unlikely in "just" a VW air cooled that someone put a filter on.
Is this a "race beetle"? Unless this is some max'd out Empi-fied engine that pulls sub 12's in the quarter, I really can't see it needing a race filter.
This would have to be some radically hi-per setup for this to happen, imo. It can surely happen with some engine that goes from 1500-7500rpm in a few seconds. The can will be the weak link and your relief port on the pump can be overwhelmed ..and there is surely some inertia/time/physics thing that could/would come into play ..but I'd find it unlikely in "just" a VW air cooled that someone put a filter on.
Is this a "race beetle"? Unless this is some max'd out Empi-fied engine that pulls sub 12's in the quarter, I really can't see it needing a race filter.
Gary, let me say the VW guys have been retrofitting the Ford full size oil filter onto VW air-cooled cars since the 70's. The shop I am referring to is Gene Berg Ent, in Orange, Ca. Basically, the outlet for the oil pump is plugged with a 1/4npt plug, an aftermarket oil pump cover is installed that has a fitting to allow the oil flow to now exit the engine, pass thru the new oil filter, and oil coller if needed, and then re-enter the oil into the engine case. All this is done before the relief valve.
After becomming a bitog'er, I learned about quality filters, in lieu of using Fram, and as I was cross referencing the various Ford full size oil filters, it became obvious that some of the the engine oil filters also cross to the Allison spin-on trans filter. IE: HP1 and the Wix 1622 .
One particular installation is this oil filter system on my stock 1974 bug using the stock oil pump which has 26mm gears. The other installation is a 1971 bus that has this Ford full sized oil filter, Purolator L39001, in addition to a Baldwin B164 By-pass filter, and with a 1 1/2 qt sump bumps my oil capacity to approx 7 qts of Shell Rotella oil.
This retrofit became popular when Gene Berg stated in his catalog that a late '50's study showed substantial wear from the lack of filtered oil.
After becomming a bitog'er, I learned about quality filters, in lieu of using Fram, and as I was cross referencing the various Ford full size oil filters, it became obvious that some of the the engine oil filters also cross to the Allison spin-on trans filter. IE: HP1 and the Wix 1622 .
One particular installation is this oil filter system on my stock 1974 bug using the stock oil pump which has 26mm gears. The other installation is a 1971 bus that has this Ford full sized oil filter, Purolator L39001, in addition to a Baldwin B164 By-pass filter, and with a 1 1/2 qt sump bumps my oil capacity to approx 7 qts of Shell Rotella oil.
This retrofit became popular when Gene Berg stated in his catalog that a late '50's study showed substantial wear from the lack of filtered oil.
I just installed a transmission remote filter system to my F150. I also have looked at the filters you mentioned since my kit mentioned ph8a or hp1 as filters for my setup. The wix alternative to the HP1 is listed as a transmission oil filter. THe main difference I can see is the HP1, Wix 51622, Purolator 39001 are rated for a burst strength of 500 psi while the ph8a and alternatives are rated for around 275 psi
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All this is done before the relief valve.
I'm still trying to figure what difference this makes.
This might be (sorta) what you're talking about. It basically routes the pump output through the filter and back along its merry way.
There has to be some detail they're leaving out ..or don't really understand themselves.
While any filter is a vast improvement over none, the Fram HP barely qualifies.
All this is done before the relief valve.
I'm still trying to figure what difference this makes.
This might be (sorta) what you're talking about. It basically routes the pump output through the filter and back along its merry way.
There has to be some detail they're leaving out ..or don't really understand themselves.
While any filter is a vast improvement over none, the Fram HP barely qualifies.
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Gary, those combo pump/filters are not very popular with engine that have quite a bit of cash/time involved because the tolerances within the pump are loose and the transition from the gears to the filter and back into the pump is restrictive. Also, some exhaust systems will not allow this setup as it will hit, or is very close. The more "exotic" setup is where the oil is taken out of the engine and re-entered into the engine at an accessable place on the engine case. As I stated earlier, this has been done for decades, with the only warning I know of is to assure a high quality oil filter is used. Note to all: trying to find a popular pic or schematic of this setup for you to see.
But the question of the day is, these filters that are used as hydraulic filters such as the Wix 51622, are they the same as,say a HP1 Fram? The dimensions and specs seem to indicate they are. Thanks for your input, Bill
But the question of the day is, these filters that are used as hydraulic filters such as the Wix 51622, are they the same as,say a HP1 Fram? The dimensions and specs seem to indicate they are. Thanks for your input, Bill
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Years ago I was sent out to service a forklift and it had a Fram HP1 filter on the trans line . In my wisdom I had a filter that would work " A non high pressure filter" well a few days later I had to go back and replace the filter with the proper "filter" as the installed filter burst.
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