No sludge
Race Director
Joined: Oct 2005
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From: Camp Verde AZ
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Just shows the oil was changed at some sort of normal interval, you get sludge with short drives that don't heat up the motor and 15K mile oil changes.
I took a motor apart in high school shop class that had sludge so high in under the valve covers, it looked like a jello mold of the valve covers.
Doug
I took a motor apart in high school shop class that had sludge so high in under the valve covers, it looked like a jello mold of the valve covers.
Doug
Safety Car
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From: Georgetown TX
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My first $75 car a 55 Ford had so much sludge we had to use putty knives. That was 47 years ago and I swore I would never never own an engine like that again. I have used Valvoline all my life (synthetic the past 5 years) and have never paid for an oil change. I have taught all three of my kids (one son and twin girls) the importance of preventative maintenance. Oh to dump the old oil in the alley to keep the dust down like the old days. That old alley behind my mom's house has the greenest grass you will ever see.
John F
John F
Thread Starter
Melting Slicks
Joined: Sep 2003
Posts: 3,050
Likes: 2
From: Orange Ct
I have always changed and used a quality oil every 3k or at the beginning and end of the season. ( I know this is true because it said it was quality oil on the can). I may leave a message on the inside. Something like "Special Duntov engine no.1, do not for use in production"
Le Mans Master
Joined: Jun 2004
Posts: 9,015
Likes: 331
From: Southeast Missouri
Just shows the oil was changed at some sort of normal interval, you get sludge with short drives that don't heat up the motor and 15K mile oil changes.
I took a motor apart in high school shop class that had sludge so high in under the valve covers, it looked like a jello mold of the valve covers.
Doug
I took a motor apart in high school shop class that had sludge so high in under the valve covers, it looked like a jello mold of the valve covers.
Doug
Melting Slicks
Joined: Oct 2004
Posts: 2,730
Likes: 92
From: Lakeland FL
Another use for old oil
My first $75 car a 55 Ford had so much sludge we had to use putty knives. That was 47 years ago and I swore I would never never own an engine like that again. I have used Valvoline all my life (synthetic the past 5 years) and have never paid for an oil change. I have taught all three of my kids (one son and twin girls) the importance of preventative maintenance. Oh to dump the old oil in the alley to keep the dust down like the old days. That old alley behind my mom's house has the greenest grass you will ever see.
John F
John F
Team Owner
Joined: Mar 2003
Posts: 26,118
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From: Greenville, Indiana
I'd say it shows you've been using high detergent oil, the pcv system is working and your rings probably don't have a lot of blowby.
Prior to today's oil, pcv systems, it was common as others have said to open an engine and find the valve covers packed with sludge, just making an outline of the valve gear and the pan with enough sludge in it you could scoop it with your hand. That's even with doing the recommended frequent oil/filter changes.
They used to plug up so bad, the sludge would block the oiling system going to the rockers and you'd have to add an external oiling kit. A copper line running from an oil galley on the outside of the engine to the rocker covers. Lot's of old Stove Bolts and Y blocks had them.
Prior to today's oil, pcv systems, it was common as others have said to open an engine and find the valve covers packed with sludge, just making an outline of the valve gear and the pan with enough sludge in it you could scoop it with your hand. That's even with doing the recommended frequent oil/filter changes.
They used to plug up so bad, the sludge would block the oiling system going to the rockers and you'd have to add an external oiling kit. A copper line running from an oil galley on the outside of the engine to the rocker covers. Lot's of old Stove Bolts and Y blocks had them.
Last edited by MikeM; Apr 3, 2010 at 10:14 AM.
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Brett Foote
Racer
Joined: Oct 2005
Posts: 478
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From: Redlands CA
About 40 years ago oil contained a high percentage of paraffin wax. This is what caused the sludge. The wax cooled and settled in the cooler parts of the engine. There were some big lawsuits against the oil companies and they changed to low paraffinic oils with a high detergent loading, hence the clean engine we see today. I too remember opening up an engine and seeing a half inch of black sludge in places.
Team Owner
Joined: Mar 2003
Posts: 26,118
Likes: 1,874
From: Greenville, Indiana
About 40 years ago oil contained a high percentage of paraffin wax. This is what caused the sludge. The wax cooled and settled in the cooler parts of the engine. There were some big lawsuits against the oil companies and they changed to low paraffinic oils with a high detergent loading, hence the clean engine we see today. I too remember opening up an engine and seeing a half inch of black sludge in places.
Burning Brakes
Joined: Jan 2007
Posts: 960
Likes: 25
From: Middlesboro KY
We had terrible build up of sludge in the wife's volvo. Volvo shop charged $2000 to clean up the mess. They wanted another $450 to do more after only driving 60 miles from their shop when the "check engine" light came on again for the same problem elsewhere in the engine. Didn't go back for the second cleaning. Google search resulted in several similar occurances in same model volvo as well as some VWs. The solution according to my search was application of a product called Auto Rx. Ever heard of it? It's an internal engine wash. Anyway, always been a follower of "ain't no cure in a can!" but what the heck, put some in the wife's car. Might consider the vette someday if it proves effective.
Melting Slicks
Joined: Jun 2008
Posts: 2,110
Likes: 30
From: Columbia, SC
I had a professor who used to be an engineer of some type for GM in the 60s/70s. Horror stories abounded of the insane amounts of paraffin build up everywhere whenever they opened up an engine that saw regular changes with Quaker State.
Racer
Joined: Oct 2005
Posts: 478
Likes: 5
From: Redlands CA
The high paraffinic oils did come from the Pennsylvania oil fields. Yes it was Quaker State and Pennzoil. They paid for many engine replacements and overhauls. I quit using them decades ago and switched to Castor oil then Mobile 1 in all my vehicles. I've never had a oiling problem since.
Thread Starter
Melting Slicks
Joined: Sep 2003
Posts: 3,050
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From: Orange Ct
After I got the pan off and inspected the bottom end I found that the oil pickup from the pump was easy to move up and down. I see it's recommended that the tube be welded to the pump (at the right position). It seems to be possible to push it up if the baffles in the pan hit the pickup when replacing the pan. Was it originally just a force fit that kept it in the right position?
Race Director
Joined: Feb 2004
Posts: 14,984
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From: CT
My first $75 car a 55 Ford had so much sludge we had to use putty knives. That was 47 years ago and I swore I would never never own an engine like that again. I have used Valvoline all my life (synthetic the past 5 years) and have never paid for an oil change. I have taught all three of my kids (one son and twin girls) the importance of preventative maintenance. Oh to dump the old oil in the alley to keep the dust down like the old days. That old alley behind my mom's house has the greenest grass you will ever see.
John F
John F
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From: northern california
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My memory of engines in the '60s is that of sludge being extremely common,. I recall many engines so full of it you could barely find the valve train. This was in an impoverished part of northern Georgia and, with hindsight, I'd speculate regular oil changes were not considered one of life's necessities.
Late in 1966, I bought my '57 Shaker, compleat with an underwhelming 265 2bbl engine. Having a bad case of tinkeritis back then, I popped a valve cover to see how much sludge there was. There was none. Zip. Zero. Zilch. The fellow from whom I bought the car had changed the oil every 1000 miles and that's when I became a believer in regular, frequent changes.
Oh, and his oil of choice was Quaker State.
Jim
Late in 1966, I bought my '57 Shaker, compleat with an underwhelming 265 2bbl engine. Having a bad case of tinkeritis back then, I popped a valve cover to see how much sludge there was. There was none. Zip. Zero. Zilch. The fellow from whom I bought the car had changed the oil every 1000 miles and that's when I became a believer in regular, frequent changes.
Oh, and his oil of choice was Quaker State.
Jim
Race Director
Joined: Feb 2007
Posts: 15,422
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From: northern california
C2 of Year Finalist (track prepared) 2019
They used to plug up so bad, the sludge would block the oiling system going to the rockers and you'd have to add an external oiling kit. A copper line running from an oil galley on the outside of the engine to the rocker covers. Lot's of old Stove Bolts and Y blocks had them.
Jim