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Cutting open my oil filter [message #371524]

Thu, 16 November 2023 13:40

Greg C.

Messages: 224
Registered: October 2019
Location: Knoxville, TN

Karma: 0

Senior Member

This is probably something Matt Colie would have a lot of experience with, being "a refugee from dyno land".

How much grit and grime would be considered normal in the bottom of an oil filter? Any? None?

Does the pressurized oil come in the 3/4" inlet and flow out the little holes, or vice versa? In other words, is the dirt on the inside of the paper pleats or the outside?

My paper looks clean on both sides, but I do have some grit, most of it much finer than sand, on the bottom of the filter housing. I cut it apart with tin snips, so no abrasive disc was used.

The oil has been in there a while, but only has about 1500 miles on it, if that. It has been changed twice during my tenure, once when I got it home, and again after changing the timing gear and intake manifold. It is synthetic. I've heard that changing to synthetic from dino oil can result in dirt being dislodged from internals, but I don't have any information on what oil the PO used in it.

Greg Crawford KM4ZCR Knoxville, TN "Ruby Sue" 1977 Royale Rear Bath 403 Engine American Eagle Wheels Early Version Alex Sirum Quad bags

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Re: Cutting open my oil filter [message #371525 is a reply to message #371524]

Thu, 16 November 2023 16:56

Matt Colie

Messages: 8547
Registered: March 2007
Location: S.E. Michigan

Karma: 7

Senior Member

Greg,

You are correct and I can. Most lube oil filters flow from the outside to inside. I am going to have to check because that is not a given and lots of manufacturers do it differently. If you are seeing sand in the bottom, I would be surprised, but that is not uncommon for NEW engines. If it is finer than the sand you know, that is core sand and it was expected to be trapped in the filter. That keeps coming out of the castings about forever (until the engine is scrapped). The black gunk is also common, that is combustion by products and if the engine is not new, then that should also be expected. That is what the filter is really there to catch.

You say clean inside and out? We always took a box knife and cut the filter paper clear of the ends so it could be flattened out. Then we would spread it out under a lot of light and look for "sparklies". Those are usually aluminum and lead that came off the bearings. Even after that, there was always an aluminum cookie sheet available that we could lay the paper out and go over it with a magnet. When you do this, there will always be some light stuff that sticks to the magnet. This is why engines have a limited life.

If you don't find flakes that are big enough to see with the naked eye, you don't have a problem. Or, at least not an immediate problem.

If this is not enough answer, just say so. As you may have guessed, I can go on about this for another page - maybe more.

Matt_C

Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit

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Re: Cutting open my oil filter [message #371526 is a reply to message #371524]

Thu, 16 November 2023 18:55

JohnL455

Messages: 4447
Registered: October 2006
Location: Woodstock, IL

Karma: 12

Senior Member

Flow on our engines is in the small holes and out the center. Original filter was PF-30 with no anti drain back flap as Olds filter is mostly vertical, not needed. GM discontinued the PF-30 and superseded with the PF-24 borrowed from the Buick stable which does have the anti drain back valve visible at the small holes. Buick needs the check valve as filter sits sideways. I use the Wix standard grade NOT XP. Standard has 20 micron rating by Wix. XP has no rating by Wix. 51258 fits 455. 51522 for small block 403

John Lebetski
Woodstock, IL
77 Eleganza II

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Re: Cutting open my oil filter [message #371527 is a reply to message #371524]

Thu, 16 November 2023 19:58

Greg C.

Messages: 224
Registered: October 2019
Location: Knoxville, TN

Karma: 0

Senior Member

Thank you, Matt, and John. I will spread the paper out and look at it in sunlight. Your answer does make me feel better. So a little gunk is to be expected at each oil change.

I've been using the 51258 on my 403. Seems like I looked it up somewhere and that's what I've used both times.

Is that a problem? It's a short filter, and I use long filters when possible, but it looks like a long filter would be awfully close to the half shaft. But that may be because of the way my filter adapter is clocked.

Greg Crawford KM4ZCR Knoxville, TN "Ruby Sue" 1977 Royale Rear Bath 403 Engine American Eagle Wheels Early Version Alex Sirum Quad bags

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Re: Cutting open my oil filter [message #371528 is a reply to message #371524]

Thu, 16 November 2023 21:05

JohnL455

Messages: 4447
Registered: October 2006
Location: Woodstock, IL

Karma: 12

Senior Member

From the interchange 455 and 77 403 used the 51258. In 78 they went to the tiny diameter sized 51522. I don’t like the long filters for the reason you mentioned and more vulnerable to tire shards etc.

John Lebetski
Woodstock, IL
77 Eleganza II

[Updated on: Thu, 16 November 2023 21:06]

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Re: Cutting open my oil filter [message #371529 is a reply to message #371525]

Fri, 17 November 2023 09:58

Matt Colie

Messages: 8547
Registered: March 2007
Location: S.E. Michigan

Karma: 7

Senior Member

Greg,

I always chuckle when I hear about larger and smaller lube oil filter on spark ignition engines.

If your engine is creating enough debris so the size of the filter matters, you have problems so big that the filter will probably not save the engine. Many production engines never had a real oil filter. None of the air cooled VW engines had an oil filter, just a screen to keep any big chunks from damaging the lube oil pump.

So, use what ever filter you like and do not worry about it....

Now Diesels are another issue. They product combustion by-products that are large. Those chunks of carbon can't damage anything on their own because they are too soft, but they can accumulate and interrupt the flow of lube oil in places it needs to go.

Matt_C

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Re: Cutting open my oil filter [message #371530 is a reply to message #371529]

Sat, 18 November 2023 18:50

Greg C.

Messages: 224
Registered: October 2019
Location: Knoxville, TN

Karma: 0

Senior Member

Thanks Matt.

I cut out my filter paper and spread it out in sunlight. I didn't see any "sparklies". The gunk that was in the pleats could be smeared and mashed with my fingers, and didn't have a lot of grit to it, so this was encouraging.

Didn't see much that was picked up by a magnet out of the paper, or in the bottom of the filter.

I remember helping a new owner a year or two back that had low oil pressure. He had driven it from Iowa with the oil light coming on at every stoplight. He kept saying it was full of oil, and he had just gotten it changed the day before. He mistakenly thought the transmission dip stick was the engine dipstick, and pulled it to show me it was full. He had paid a garage in Iowa to change his oil, but they didn't do it.

It took three quarts to get it back on the stick, so it had maybe a quart in the pan. We changed the oil and filter, and checked pressure with a mechanical gauge. It idled at 40 psi. He drove it from Knoxville to Raleigh with no issues. I really didn't expect it to run that long. But I haven't heard from him since.

I cut open his filter, and it was loaded with debris in the bottom of the filter that swirled around when you moved a magnet on the opposite side of the metal filter case. I think he was lucky to get to Raleigh.

Greg Crawford KM4ZCR Knoxville, TN "Ruby Sue" 1977 Royale Rear Bath 403 Engine American Eagle Wheels Early Version Alex Sirum Quad bags

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Re: Cutting open my oil filter [message #371531 is a reply to message #371524]

Sun, 19 November 2023 08:38

JohnL455

Messages: 4447
Registered: October 2006
Location: Woodstock, IL

Karma: 12

Senior Member

Ha. Guessing his Dexron was also brown not red, leading him to believe that was engine oil on the trans stick.
At least they didn’t put coolant in the oil fill! That one is seldom a good outcome.

John Lebetski
Woodstock, IL
77 Eleganza II

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Re: Cutting open my oil filter [message #371532 is a reply to message #371524]

Sun, 19 November 2023 11:05

Larry

Messages: 2875
Registered: January 2004
Location: Menomonie, WI

Karma: 10

Senior Member

At Dick Patterson's recommendation, I put a FilterMag on my oil filter. At the Corunna MI rally, Dick showed us a clear container with oil and iron metal particles in the bottom. The metal particles were of the size/grit that would pass through the paper elements of most oil filters. He shook it up to disperse the particles in the oil, and then applied the FilterMagg to the outside of the container. It instantly cleared the oil of the iron particles sticking them to the side of the clear container. What a practical clear demonstration of what could be floating around in our oil. When I first installed a FilterMag 18yrs ago, for the first couple of oil changes, I cut the filter apart and was astounded at the amount of grey material that the Magnet collected on the inside of the metal filter. Convinced me that it was removing contaminates not needed. JWID

Larry

78 Royale w/500 Caddy
Menomonie, WI.

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Re: Cutting open my oil filter [message #371536 is a reply to message #371524]

Tue, 21 November 2023 13:54

JohnL455

Messages: 4447
Registered: October 2006
Location: Woodstock, IL

Karma: 12

Senior Member

When Cinnabar did my engine they installed a magnetic drain plug. Less surface area but it works. They can’t really install the FilterMag type as all their customers do not change their own oil especially on a road trip, and the FilterMag will often get discarded with old filter instead of being transferred over. Luckily only a few tiny shards ever found on drain plug over the years.

John Lebetski
Woodstock, IL
77 Eleganza II

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Re: Cutting open my oil filter [message #371537 is a reply to message #371536]

Wed, 22 November 2023 10:25

rjw

Messages: 697
Registered: September 2005

Karma: 4

Senior Member

JohnL455 wrote on Tue, 21 November 2023 14:54

When Cinnabar did my engine they installed a magnetic drain plug. Less surface area but it works. They can’t really install the FilterMag type as all their customers do not change their own oil especially on a road trip, and the FilterMag will often get discarded with old filter instead of being transferred over. Luckily only a few tiny shards ever found on drain plug over the years.

I don't know what they are talking about when they say a FilterMag will often get discarded with old filter. I have a FilterMag and I can't take the filter off without removing the magnet because it would hit the block during removal. At least that is the case in my 455 so there is no way it would be tossed with the old filter. I like the idea of magnetic drain plug since I have never opened up a used oil filter.

Richard
76 Palm Beach
SE Michigan
www.PalmBeachGMC.com

Roller Cam 455, TBI+EBL, 3.42 FD, 4 Bag, Macerator, Lenzi (brakes, vacuum system, front end stuff), Manny Tranny, vacuum step, Tankless + OEM water heaters.

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