Merc Oil Filter Study
 

I saw some posts here earlier about Merc oil filters. I am a pleasure boater with a Merc I/O. However, our filters are the same that many of you use.

I took 12 filters apart and analyzed them -- complete with pore size and flow measurements.

These filters map to the venerable AC Delco PF1218.

I have not tested the Merc Racing long version.

Coming soon will add the following filters:

Donaldson
Fleetguard
Amsoil
Mobil 1

Enjoy! Let me know what you think. Since I can't post a URL until 10 posts, you can cut off the Z on the front of this one.

Zhttp://home.earthlink.net/~memphis3/mercfilters/merc.htm

Grease

Excellent info! Wouldn't by chance have any data on Wix 51222R ?

nice work!!

we use K&N

Re: Merc Oil Filter Study
 

Great info, thanks!
Since I have a little more than 10 post, I can post the URL: ;)

http://home.earthlink.net/~memphis3/...lters/merc.htm

It looks like the "ratings" consider flow but not filtration. Am I missing something ?? Seems like the Merc filter has very good flow considering its small pore size (= good filtration).

I haven't had the pleasure of dissecting a WIX racing yet. I hope to add it to the list.

Thanks. In my opinion in this application, the K&N is a great filter. It has smaller pore size than the Merc, yet it has more media, hence more flow. I wouldn't loose sleep over using a WIX, Hastings, or Baldwin in a boat. I would be a little concerned over the AC or PureOne in a boat regarding flow -- but the filtration is excellent. They may flow enough once the oil is hot, but may be in by-pass mode longer than the others.

I may even use a by-pass filter in addition to a good flowing filter. That way you get the benefit of both worlds.

We are going to test some synthetic filters from Donaldson, Fleetguard, and Mobil 1 soon.

I made up my own rating system. They do consider flow and pore size. You can modify it to suit your emphasis (weighting system) regarding the different characteristics and come up with your own winner.

The Merc has great flow but has the largest pore size. I also wonder if the large pore size has to do with the concern if water gets in the oil it can swell the pores.

I'm sure many of you use the large canister Merc racing. I'll have to get that one and test is also. I'm assuming that the media is the same as the small canister Merc, but you never know until test time.

Wow, that is good info. Interests me because I just blocked off my bypass valves in the remote filter pad. Would be nice to know the different bypass pressures of these filters.

Looking forward to the synthetic media filter testing!

Dave

None of these filters have bypass valves. That is part of the engine. GM didn't want to rely on the filter to do the bypass, so the engine does that function. Physically, I'm not sure where the bypass is located.

Grease

The spring that you show as "leaf" or "spring" is the bypass portion of the filter. The entire filter elment will work against this spring and when over pressurized bypass oil on the top. At least that is alway how I've understood it to work. The coil spring is best because it can be over pressurized without being destroyed. The leaf can become rendered useless after repeated over pressurization. Correct me if I am wrong, but that is my understanding of hydraulic filter operation.

Dave

Normally that is the case, however in the PF1218 family of filters, there is no by-pass at all. That is the spec. Oil filter companies call this a full-flow filter. Here is a good example:

(remove the Z)

Zhttp://www.osuweb.net/~mccarter/gw/Image6.jpg

You can see that the end away from the filter opening is completely closed. That is the case on every one of these filters -- except for the Fram. The Fram's only have an opening because the endcap is paper and not metal. The leaf spring on the Fram would distort the paper endcap, so they put a hole in it to seat the leaf spring instead of the indent as the rest of the filters.

Not sure of the filter you are using, but if it is this family / application, by-pass is handled by the engine.

If you application is different you can look up that filter and see if there is a by-pass listed on that mfg's web site. If they don't say either way, look up cross references on other's sites. Someone will indicate whether full-flow or by-pass valve.

Hope this helps.

Grease

I'm still not understanding Grease. If the media becomes clogged, the pressure builds onto of the closed end, as shown in the link you posted. This pressure forces the element assembly against the spring, leaf or coil which ever is applicable. When the spring deflects, the element moves away from the inlet side of the filter (stamped piece) and allows oil to bypass the element. If this was not the case a spring would be unnecessary.

Dave

The spring on these filters is used to seat the anti-drain back valve against the open filter end and the baseplate -- and to center the media within the can.

Take the Baldwin B1428 for example (which is a cross to the AC Delco PF1218. Here is the listing from their web site:

Descriptions : Microlite Lube Spin-on

Contains : Anti-Drainback Valve

Fits : Chevrolet, GMC Automotive

Replaces : GMC 25160561

Thread : 13/16-16

O.D. : 3 11/16 (93.7)

Length : 5 11/32 (135.7)

I.Gskt : G383-B

Related to : B6 (without Anti-Drainback Valve)
B1438 (Short Version)
B1441 (with 14 PSI By-Pass Valve)

At the end, they describe other filters that have other attributes. In this case, they have the B1441 that has a by-pass valve.

What filter are you using?

I have been using the delco 1218 for the last couple of years. I also have had functioning engine mount bypass valves. In an effort to control excessive oil temps, among other things I have blocked the engine bypass valve. Now all the oil will be forced through the cooler (and filter). Because I have blocked the engine bypass, it becomes imperative that I have a filter with a bypass. I always thought the leaf or coil spring made up the bypass of the filter, the element being the poppit. I guess what you are saying is a filter with a bypass will have a seperate poppit and spring to act as a bypass.

This being said, is it safe to assume the baldwin part number B1441 (with 14 PSI By-Pass Valve) would be the filter for me? I'll have to get on their site and check it out. Thanks for the info.

Dave

Grease-

I would be interested to know what you think of the Donaldson filters. I am a Mechanical Engineer at Donaldson Company in the Diesel Exhaust Group and would like a outside opinion of our filters compared to the others.

Thanks
Don

I called and talked to Baldwin today. They confirmed that the bypass valve is a seperate spring/poppet and that the B1441 would be a good choice for me with the blocked engine bypass. I order (4) at $6.47 each. Thanks for the heads up on that Grease. :eureka:

Dave

Good Job BT and Grease. Heck, you should have waited, we could have gotten case quantities. I have always assumed the 1218 had a bypass valve too. So what happens if the engine bypass is plugged and the filter has no bypass and gets plugged? Oil pressure drops? Is the oil pressure sender downstream of the remote stuff or before it? if the pressure drops, maybe its better to have filter without a bypass, at least you know. Im still out on the whole block bypass thing anyway.

Excellent. I think you will be happy with the B1441. The Baldwin filters are very well built. They are a good compromise between filtration and flow.

I have a Donaldson P550964 in my hands that I will be adding to the comparison -- it is the map to the PF1218. It will take a few weeks to get the tests run, compiled, and updated. I will also be ordering a P166564 to test the synthetic media as well. I will hold off on my comments until then.

A lot of people thought the same as us F31. Two seperatte people specifically told me thats the way it was with the bypass. One is the freindly Napa counter guy and the other is actually a hydraulics sales engineer that works for a hydraulics supply house I buy power units from. He should know better! Wait till I get my hands on him :hothead:

Dave

Interesting....keep up the good work!

I'm glad you liked it. I am inclined to add the long canister Merc racing to the tests as well. When I googled and found your forum and saw you were discussing oil filters on your rigs AND many of you use the PF1218, you would like to see what we had done.

When you guys blow by me on the Ohio river in Cinn with my 220HP V6 I'll be thinking about you ;)

Take care, I'll check back from time to time and also post when the new filters are on-line.

Take care, I'll check back from time to time and also post when the new filters are on-line. [/B][/QUOTE]

Be sure you do, and thanks again ;)

Dave

Is there a difference in the Fram PH5 and The HP6?
Also does someone make a replacement for that filter?

Scott

Not very familiar with the HP6, but a WIX 51222R (racing) is the WIX replacement.

The PH5 does not have by-pass and the HP6 does. It appears that the gasket is quite different between the two.

Great information, Thanks for sharing with us!

Re: Merc Oil Filter Study
 

In my humble and only slightly biased opinion NO paper element filter should be used in a marine application, only a full synthetic filter or a washable screen type. Just traces of water from condensation, typical of the intermitant use of a boat engine, is enough to shut down all filter flow. If you have a bypass in the filter or in the oil adapter you will never even notice that it has happened.

-Greg

Re: Merc Oil Filter Study
 

While we are on the topic of filters what does everyone think of the "FilterMag" products? Seems like a good idea. Almost too good to be true. Have you anythoughts on them?

BH

http://www.filtermag.com

Re: Merc Oil Filter Study
 

Hey Grease. I heard that Honda OEM oil filters were very well engineered. I know there is probably no application for Merc products but was interested in your take on this filter anyways and if there are oil filters that have this type setup or are all filters similar to this? Maybe it is not all that special I don't know. But I know it was derived from testing on the NSX and then the technology shared by the company to other vehicles if not all. Here is what Honda says about the filter:

"The Honda OEM filter has an "extra check valve" in it which stops any oil from flowing into the filter until there is oil pressure in the system sufficient enough to overcome this check valve. What this does is to allow oil to bypass the filter and get to the important parts of the engine more quickly, especially on cold startups".

DO other filters have this "extra check valve" too?