ActiveFun

Whats the difference between the HP4 and the HP6?? Can you interchange the HP6 with a HP4 set up?

Back4More

The HP6 is/has a 1-1/2" threaded mount and the HP4 has a 13/16" mount.
Looks like the WIX Racing filter is pretty good.

Roger 1

Mobil 1

Strip Poker 388

I buy these at Napa for 11.75.

I have had bad luck with the regular Frams and have heard from others of collapsing.

I have a pick one one cut open if anybody want to see

HotPursuit

System 1 & amsoil 20-50

Panther

I've used the Napa Racing and the Fram HP and Wix Racing filters without any problems. The only filter I've ever had a problem with was Mobil 1 filter, it collapsed and reduced oil psi. by 50%.

mopower

I've heard of Fram collapsing. I stay with NAPA , Wix or AC Delco

Strip Poker 388

inside

Hydrocruiser

In this list the ones in bold get it done...


Oil Filter f/ most Mercruisers
FYI:The thread type on the filter is 13/16-16.

Fram Racing/HP
Fram: PH5, HP4, DG5, PH13 (no anti drainback)
Pureolator: L34631
Purolator Pure One: PL34631
A/C: PF1218, PF932
Motorcraft: FL-12A
NAPA: 1060, 1060gold
Wix: 51060
Wix Racing: 51060R, 51061R R= Racing
K&N: HP3002
Baldwin: B1428 (Top Rated)
Amsoil: SDF-24
Hastings: LF279
Fleetguard: LF3679
Mercruiser: 35-802885Q
Mobil 1: M1-302 or M1-111
Kendall: K31
Penzoil: PZ45
Quaker State: QS5
Shell: S63, SH38
Texaco: T38, T38B
Warner: PH1218
STP: S01218
Valvoline: V056
Mercury Racing

GO4BROKE

Mercruiser Oil Filter Comparison

Current Revision 2.2; February 1, 2004

Original publication date: November 15, 2003

Update: This study has been updated to include pore size and oil flow measurements. Each filter section has raw data measurements and comparisons to the other filters. Two additional filters have been added for a total of 12 filters.

In addition to physical properties, this study now analyzes pore size and oil flow of the filter media using a professional bubble point tester.

To examine all of the detailed regarding the pore size and flow tests, click below:

Pore and flow study details

This project was started to determine the quality of Mercruiser oil filters. This application also pertains to Chevrolet V6 and V8 engines that use the AC Delco PF1218 filter. The objective is not to find out what filter is best for all applications. However, general conclusions can be made for other applications.

An automotive tail-pipe cutter was used to cut the filter housings. This allowed clean cuts without damaging the filters or internal parts. Digital calipers were used to make all measurements.

All recent model 135HP 4-cylinder, V8s, and V6s with remote oil filters use the Mercruiser filter 35-802885T. Originally, the WIX 51086 was going to be compared. Since the AC Delco PF 1218 is a longer filter that also fits this application ten additional filters that mapped to it were compared. Here are the filters (in alphabetical order):

AC Delco PF1218
Baldwin B1428
Fram Extra Guard PH5
Fram Tough Guard TG5
Hastings LF279
K&N 3002
Purolator PureOne PL34631
SuperTech ST5
STP S5
Mercruiser 35-802885T
WIX 51086
WIX 51060
The Merc and WIX 51086 were the only two that are of the original short design. All others are comparable, longer, and larger capacity.

Mercruiser V6 engines without the remote oil filter configuration, use the part numbers below:

Mercruiser 35-883702K
WIX 51036
Hastings LF393
Baldwin B35-S
K&N 2001
AC Delco PF52
All of these filters in this comparison do not have by-pass valves (BPV). The BPV allows oil to by-pass the filter if it becomes clogged. My understanding is that GM/Mercruiser engines have a BPV in the engine itself, so the oil filter specification is to not have a BPV.

These filters also have anti-drain back valves (ADBV). This is a nitrile or silicon rubber seal that stops oil from exiting the intake holes when the engine is not running.

The intent of this study is to be as objective and non-biased as possible and just present observations. The following data was collected. This is included in this MS Excel spreadsheet on the “Filter Data” worksheet.

Number of intake holes
Area of intake holes
Thickness of gasket
Width of gasket seal
Weight of entire filter
Material of ADBV
Number and location of welds
Number of pleats on filter
Area of filter in square inches
Material / design of spring
Notes, positive and negative observations
In addition, the following measurements are made on the filter media:

Average large pore size
Smallest pore size
Oil flow at 10psi and 20psi with 30W oil
This data can be found on the same spreadsheet under the “Bubble Point Testing” and “Oil Flow Test” worksheets.

The bubble point testing was performed using this bubble point tester.

These filters are presented in increasing cost order. The (x of 12) numbers are the rating and comparison to all 12 filters. Higher numbers are better. The filter weight measurements have a one-half weighting. The flow rating is weighted by two. All other measurements have a weighting of one. When two numbers are listed (x-y of 12), this indicates a tie. In this case, an average is used with these numbers for the overall rating. The oil flow numbers below are for the entire filter using the effective filter area (EFA). The EFA is multiplied by the flow of the sample media to arrive at the oil flow number of x ounces of oil per minute at 10psi. While 10psi was used for ratings in this document, 20psi was also tested and is included in the Pore and flow study details document.



SuperTech ST5

Cost $1.97 -- WalMart
ADBV material: Nitrile
Spring type: leaf
Intake area: 0.345 sq/in (7 of 12)
Filter area: 305 sq/in; 56 pleats (6-7 of 12)
Total Weight: 425 grams (3-7 of 12)
Filter and endcap weight: 5 oz (5-10 of 12)


Physical Rating: 20 (5-7 of 12)

Average pore size: 42.5 µm (3 of 12)
Smallest pore size: 17 µm (5 of 12)
Oil flow @ 10psi: 10.8 oz per minute (9 of 12)


Pore and Flow Rating: 26 (5-6 of 12)



Overall Rating: 46 (6 of 12)

This filter appears to flow well and do an average job of filtration. It appears to be made by Champion and has a solid construction and very similar in physical characteristics to the AC Delco and STP filters.

[ST 5 pictures coming soon]



Fram Extra Guard PH5 Fram website

Cost $2.99 -- Advanced Auto
ADBV material: Nitrile
Spring type: leaf
Intake area: 0.227 sq/in (1-2 of 12)
Filter area: 183 sq/in; 36 pleats (2 of 12)
Total Weight: 400 grams (1-2 of 12)
Filter and endcap weight: 2.5 oz (1 of 12)


Physical Rating: 5 (1 of 12)

Average pore size: 32.5 µm (8 of 12)
Smallest pore size: 14 µm (8-10 of 12)
Oil flow @ 10psi: 4.0 oz per minute (1 of 12)


Pore and Flow Rating: 19 (1 of 12)



Overall Rating: 24 (1 of 12)

This filter appears to have good filtration media but flow poorly. Much of the poor flow rating is due to the small surface area of the filter media.

Note that the Fram PH6606 is the cross-reference to the Merc 35-802885T filter. It is the same size as the Merc filter. However, it was unavailable locally and required a special order for $9. Instead it is compared here to the longer filter PH5 for $3 that was readily available.

Both Frams (EG and TG) had a different design than all the others. Instead of metal ends to hold the filter material in place they had a paper material. Since the leaf spring at the bottom of the filter cannot press against paper, both ends of the filter have holes. The leaf spring has a raised circular form to plug the hole at the bottom of the paper endcap. The black nitrile ADV has a long neck on it that inserts into the hole in the top endcap. The leaf spring holds everything in place.

This filter has the smallest filter area of the large canister filters (except for smaller canister Merc and WIX). The intake holes have the smallest combined area of all filters (both Frams are the same in this regard).



Here are the internals of the PH5 showing the leaf spring that fills the hole of the bottom endcap.



This next photo shows the Fram PH5 internal canister. It has fewer holes than most filters. It has pronounced ribs for strength, although the canister gage appears less than the other filters. One positive design only on the Frams and two other filters (Baldwin and Hastings) is the metal band to crimp the start and stop pleats together. Many filters in this comparison used an adhesive.





STP S5 STP website

Cost $2.99 -- Advanced Auto
ADBV material: Nitrile
Spring type: leaf
Intake area: 0.328 sq/in (5-6 of 12) (5-6 tie)
Filter area: 326 sq/in; 60 pleats (8-9 of 12)
Total Weight: 425 grams (3-7 of 12)
Filter and endcap weight: 5 oz (5-10 of 12)


Physical Rating: 20 (5-7 of 12)

Average pore size: 38 µm (5 of 12)
Smallest pore size: 23 µm (1 of 12)
Oil flow @ 10psi: 10.5 oz per minute (8 of 12)


Pore and Flow Rating: 22 (3 of 12)



Overall Rating 42 (5 of 12)

This filter appears to flow well and have low to average filtration ability.

The STP S5 and the next filter, the AC Delco 1218 are identical filters in appearance. However, their media differs. Both filters are made by Champion filter. Note the "1" marking that is on the top of the filter.



Another comment about these two filters is that Mercury makes a "Mercury Racing" filter -- the 35-16595T. Outside appearance "signature" is the same as these two: the "1" marking, 5 intake holes with one larger than the other, eight seal pinch retainers, eight welds under the seal, and the same pattern of canister holes. Your choice is the STP at $3, the AC at $3.50, or the Mercury Racing at $11.

Here are the internal parts of the STP 5:



Here is the internal canister showing the size and pattern of holes. The ADBV has a good seal on the high lip of the top of the endcap. The filter material is very thick.



================================================== ====================================

AC Delco Duraguard PF1218 AC Delco website

Cost $3.49 -- Advanced Auto
ADBV material: Nitrile
Spring type: leaf
Intake area: 0.328 sq/in (5-6 of 12)
Filter area: 326 sq/in; 60 pleats (8-9 of 12)
Total Weight: 425 grams (3-7 of 12)
Filter and endcap weight: 5 oz (5-10 of 12)


Physical Rating: 20 (5-7 of 12)

Average pore size: 27.5 µm (10 of 12)
Smallest pore size: 14 µm (8-10 of 12)
Oil flow @ 10psi: 7.6 oz per minute (5 of 12)


Pore and Flow Rating: 29 (9-10 of 12)



Overall Rating 49 (7 of 12)

This filter appears to flow average and have very good filtration ability.

As mentioned in the STP section, this filter is identical in appearance to the STP S5 and the Mercury Racing 35-16595T. However, the filter media tests revealed that they are quite different. HosHere are photos showing top plate, assembly parts, and internal canister holes and filter.











Hastings LF279 Hastings Filters website

Cost $4.19 -- Local auto parts store
ADBV material: Nitrile
Spring type: spring
Intake area: 0.393 sq/in (10-11 of 12)
Filter area: 264 sq/in; 44 pleats (4 of 12)
Total Weight: 460 grams (8-9 of 12)
Filter and endcap weight: 5 oz (5-10 of 12)


Physical Rating: 23 (8 of 12)

Average pore size: 46 µm (2 of 12)
Smallest pore size: 21 µm (2-3 of 12)
Oil flow @ 10psi: 16.9 oz per minute (12 of 12)


Pore and Flow Rating: 29 (9-10 of 12)



Overall Rating 51 (9 of 12)

This filter appears to flow excellent and has lower than average filtration capability.

The Hastings filter has the second fewest pleats at 44, which gives it the least amount of filter surface area of the large canister filters. However, I believe this is a fluke manufacturing defect as Hastings technical support indicates that this filter should have 100 more sq / in of media.

It has eight intake holes in a small circle with eight welds.



The Hastings has a spring and nitrile ADBV. The filter pleats were not very evenly spaced.



Baldwin Filters manufacturers Hastings filters. One common feature of both of these filters is the identical canister core. Instead of round holes it has formed perforations. The start and end of the filter are held together with a metal band crimped on the inside of the filter.





Fram Tough Guard TG5 Fram website

Cost $4.95 -- Advanced Auto
ADBV material: Silicon
Spring type: leaf
Intake area: 0.227 sq/in (1-2 of 12)
Filter area: 274 sq/in; 46 pleats (5 of 12)
Total Weight: 400 grams (1-2 of 12)
Filter and endcap weight: 3 oz (2 of 12)


Physical Rating: 8 (2-3 of 12)

Average pore size: 26 µm (11 of 12)
Smallest pore size: 12 µm (11 of 12)
Oil flow @ 10psi: 5.1 oz per minute (3 of 12)


Pore and Flow Rating: 28 (7-8 of 12)



Overall Rating 36 (3 of 12)

This filter appears to have excellent filtration capability and lower than average flow.

The Fram TG filter shares the smallest intake hole area as its brother, the Fram EG, at 0.227 sq/in. This is the only filter outside of the WIX and PureOne filters that has the silicon ADBV. Silicon is supposed to be less prone to harden after being subject to long exposure to hot oil.





The minor differences between this filter and the lower priced Fram EG is the silicon ADBV, 10 more pleats, 90 sq/in more filter area, and a slightly thicker filter material.

The other similar design the TG has with the EG is that it has cardboard or paper endcaps with an open hole on the bottom. The leaf spring plugs this hole.

Here is the leaf spring shown with the circular form to plug the bottom endcap hole.



Here is the leaf spring installed.



Here is the inside canister showing the hole size and pattern.





Purolator PureOne PL34631

Cost $4.99 -- Meijer
ADBV material: Silicon
Spring type: leaf
Intake area: 0.440 sq/in (12 of 12)
Filter area: 330 sq/in; 62 pleats (10 of 12)
Total Weight: 470 grams (10 of 12)
Filter and endcap weight: 5 oz (5-10 of 12)


Physical Rating: 31 (11 of 12)

Average pore size: 24 µm (12 of 12)
Smallest pore size: 11 µm (12 of 12)
Oil flow @ 10psi: 4.7 oz per minute (2 of 12)


Pore and Flow Rating: 28 (7-8 of 12)



Overall Rating: 59 (10 of 12)

[Pure One pictures coming soon]

This filter appears to have excellent filtration capability and much lower than average flow.



Baldwin B1428 Baldwin Filters website

Cost $4.99 -- Truck Pro
ADBV material: Nitrile
Spring type: spring
Intake area: 0.319 sq/in (4 of 12)
Filter area: 413 sq/in; 68 pleats (12 of 12)
Total Weight: 500 grams (11 of 12)
Filter and endcap weight: 6 oz (12 of 12)


Physical Rating: 28 (10 of 12)

Average pore size: 31 µm (9 of 12)
Smallest pore size: 14 µm (8-10 of 12)
Oil flow @ 10psi: 8.1 oz per minute (6-7 of 12)


Pore and Flow Rating: 31 (12 of 12)



Overall Rating 59 (10-11 of 12)

This filter appears to have very good filtration capability and better than average oil flow.

Baldwin filters are more difficult to locate than household name brands. However, they can be found by locating a distributor on their website.

Here is the signature end plate of a Baldwin filter. There are five equally spaced intake holes.



Instead of having a neck for the ADBV to seal against, the Baldwin filter has a separate plastic ring that seals against the canister. The ADBV is large because of the large circle of intake holes.

Like the WIX and Hastings, the Baldwin also uses a spring to hold everything in place and puts pressure on the ADBV to seal it against the canister. The start and end sections of the media are held together by a metal clip instead of adhesive.



Here you can see the dense filter material and 68 pleats along with the Hastings-like metal inside canister.



WIX 51060 WIX Filters website

Cost $4.99 -- Local auto parts store
ADBV material: Silicon
Spring type: spring
Intake area: 0.393 sq/in (8-11 of 12)
Filter area: 305 sq/in; 60 pleats (6-7 of 12)
Total Weight: 460 grams (8-9 of 12)
Filter and endcap weight: 5 oz (5-10 of 12)


Physical Rating: 24 (9 of 12)

Average pore size: 37 µm (6 of 12)
Smallest pore size: 16 µm (6-7 of 12)
Oil flow @ 10psi: 8.1 oz per minute (6-7 of 12)


Pore and Flow Rating: 26 (5-6 of 12)



Overall Rating 50 (8 of 12)

This filter appears to have better than average filtration and flow and rates good to very good overall.

The WIX 51060 is the large brother to the WIX 51086. Other than the Fram TG5, these are the only filters with silicon ADBVs. However, the WIX ADBV is a much thicker valve than the Fram. The Fram TG5 silicon was more the thickness of the other nitrile valves.

The WIX endcaps feature eight 1/4" intake holes giving it the same intake area as the Hastings and K&N.



Here are the parts for the WIX 51060.





And the inside canister exposed:





WIX 51086 (small canister) WIX Filters website

Intake area: 0.393 sq/in (8-11 of 12)
Filter area: 185 sq/in; 56 pleats (3 of 12)
ADBV material: Silicon
Total Weight: 425 grams (3-7 of 12)
Filter and endcap weight: 4 oz (4 of 12)
Spring type: spring
Cost $5.99 -- Local auto parts store


Physical Rating: 17 (4 of 12)

Average pore size: 35 µm (7 of 12)
Smallest pore size: 16 µm (6-7 of 12)
Oil flow @ 10psi: 5.3 oz per minute (4 of 12)


Pore and Flow Rating: 22 (2-3 of 12)



Overall Rating 39 (4 of 12)

This filter appears to have better than average filtration and flow below average. However, regarding flow it should only be compared to the Mercruiser filter in this study because it has the same canister size.

This filter is physically similar to the larger canister WIX 51060 and is the direct replacement size for the Mercruiser 35-802885T.

Here is the baseplate:







================================================== =====================================

Mercruiser 35-802885T

Cost $6.95 -- Local marine store
ADBV material: nitrile
Spring type: leaf
Intake area: 0.297 sq/in (3 of 12)
Filter area: 182 sq/in; 56 pleats (1 of 12)
Total Weight: 425 grams (3-7 of 12)
Filter and endcap weight: 3.75 oz (3 of 12)


Physical Rating: 8 (2-3 of 12)

Average pore size: 52 µm (1 of 12)
Smallest pore size: 21 µm (2-3 of 12)
Oil flow @ 10psi: 13.1 oz per minute (10 of 12)


Pore and Flow Rating: 24 (4 of 12)



Overall Rating 32 (2 of 12)

This filter appears to have very good to excellent flow and low to below average filtration.

This filter has the same characteristics as other Champion made filters (the same as the AC Delco and STP). While it doesn't have a "1" marking on the baseplate, it has a "3" marking.

It has five equally size intake holes, a nitrile ADBV, and 182 sq/in of media. A leaf spring holds everything together.

Here is the baseplate:



Here are the internal parts:



Here is a look at the inside tube:





K&N 3002 K&N website

Cost $9.95 -- Advanced Auto
ADBV material: nitrile
Spring type: leaf
Intake area: 0.393 sq/in (8-11 of 12)
Filter area: 343 sq/in; 56 pleats (11 of 12)
Total Weight: 530 grams (12 of 12)
Filter and endcap weight: 5.5 oz (11 of 12)


Physical Rating: 32 (12 of 12)

Average pore size: 41 µm (4 of 12)
Smallest pore size: 19 µm (4 of 12)
Oil flow @ 10psi: 13.2 oz per minute (11 of 12)


Pore and Flow Rating: 30 (11 of 12)



Overall Rating 62 (12 of 12)

This filter appears to have lower than average filtration and excellent flow.

This filter is the heaviest at 530 grams. It has eight equally sized 1/4" intake holes. It has a nitrile ADBV and a leaf spring. It appears that Champion Filters also makes this filter.

This filter flows well and has is in the lower third for filtration ability.

Here is the baseplate:



The internal parts:



And the core:





Conclusion

One must read the complete pore and flow discussion before drawing any conclusions.

In that discourse, the point is made that the oil used for the oil flow tests was at room temperature. Hot oil will flow many times the rate over room temperature oil.

Yes, it appears that there are better alternatives to the Mercruiser oil filter in this application.

While the pore and flow tests were very accurate, there are certainly imperfections in the rating system. Filters within two or three places of each other should be considered and their raw data scores evaluated. This data is described in detail in the pore and flow discussion.

Not surprisingly, filtering ability relates inversely to flow. However, many filters with high filtering ability compensate by having higher filter area.

For example, the Baldwin rates as 9 of 12 in pore size but 6-7 of 12 regarding flow. It also has the most filter area of all filters in this study. The Baldwin, AC Delco, and WIX 51060 all appear to be a good compromise between pore size and flow.

If one is interested in flow for this application, the K&N provides the best flow with better filtration than the Mercruiser filter.

If one is considering the small canister size because of physical room in the engine compartment, the Mercruiser and WIX 51086 have about the same filter area. The WIX has a larger intake area, silicon ADBV, and a sturdy spring to keep everything together. The WIX filter media is much better, but the Mercruiser flows better – among the top three in this study even though it has less media than all.

The PureOne filter has the best filtering ability of all compared filters; however, it has the second worst flow ratings. One would have to ask, “would the PureOne flow enough in this application when the manufacturers filter is specified to flow many times more?” That is the danger of using an oil filter that is not specifically mapped to your application.

In a direct mapped application such as an auto oil filter, the PureOne, AC Delco, Baldwin, and WIX would appear to be good choices (provided their media is similar in different applications). One would have to feel comfortable with the Fram cardboard end construction of the EG and TG series and low filter media area to choose them over these four filters.

In this application, a good compromise would be to use a full flowing larger sized filter such as the Mercruiser, K&N, Hastings, SuperTech, or STP and add a by-pass filter such as an Oilguard, Amsoil, or Motor Guard.

Disclaimer and cautions

Since many filter manufacturers contract out their filters, one must be careful that future filters from these vendors are the same as what is presented here. One way to do this is to compare the outside markings of new filters to these pictures.

Just because one filter appears to be a good choice for this application, does not mean that it will be the best for other automotive applications. Other applications involve by-pass valves and other features that may or may not make that same filter the best choice.

Be sure to check your application. There is no guarantee, express or implied, that these filters will work in your application.



Additions / corrections since original publication

January 28, 2004

· Fixed error in pore and total rating system in both .xls file and main document. Raw data did not change. Some filters changed position by one ranking. Some stayed the same. One filter changed by two rankings. As mentioned in the summary, filters that are within 3 positions of each other should be considered very similar. This rating system is a rough attempt at trying to establish a ranking system by weighting different filter attributes.

January 25, 2004

o Added pore and flow data. Added link to pore and flow detail report. Added introduction regarding pore and flow data. Added ranking numbers. Removed first person narrative. Modified conclusion to account for pore and flow data.