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Just changed the oil on the ‘61 Olds 98, after doing the MMO soak in two cylinders, and there was lots of crud in the old oil. Some is magnetic, the only chunks that stuck to the yellow magnet are pictured. Any ideas why so much gunk in the oil? Some looks to be orange colored, and it all breaks apart by squishing it between my fingers.
This oil was about 3 months old with barely 50 miles driven on it. Mobil 1 filter, 10w-30 conventional oil.
Could be many things, valve seal material, corrosion, timing set gear material, bearing material, pieces of carbon. If you decide to pull the oil pan be certain to look deep inside the oil pickup. At this point I'd do another oil and filter change and cut the old filter open to look inside.
You might be wasting a few bucks at the moment with Mobil 1 filters untill it cleans up after a few oil changes.
Could be many things, valve seal material, corrosion, timing set gear material, bearing material, pieces of carbon. If you decide to pull the oil pan be certain to look deep inside the oil pickup. At this point I'd do another oil and filter change and cut the old filter open to look inside.
You might be wasting a few bucks at the moment with Mobil 1 filters untill it cleans up after a few oil changes.
For now, I'll do another oil change, and cut inside the filter I just removed, as well as this newest one I just put on today. I will use a cheaper filter until it clears up, if it clears up.
Just use a good filter, like a Wix. Don't use the extra long life or "synthetic" filters - those actually have *larger* holes so they don't clog up and can be used for 10,000 miles. "dirty oil is better than no oil" seems to be the thought process with the new stuff. Do a few changes with short-ish (500 to 1000 mile) intervals and see how it goes.
It's real common to have lots of burnt oil under the intake due to the exhaust crossover. I'm not as familiar with the pre-65 engines, but I expect the intake/crossover/turkey tray setup is pretty similar. Chunks will break loose from time to time. Seeing lots of silver or copper sparkle in the filter (say, if it looks like a disco ball threw up inside every fold) is a sign of a real bad problem. A tiny bit of sparkle (you notice a few specs here and there if you look hard) doesn't matter. Chunks of aluminum is bad. Chunks of oil crud is not.
The oil crud can clog the oil pickup. It's always nice to have an oil pressure gauge so you can tell if pressure drops off.
Some excellent points above, made me remember my 64 HC 330 in a Cutlass convertible. The sludge was so bad the screen at the bottom of the fill tube was clogged and there was a mountain of crud under the intake. Pulled the heads did a thorough cleanup, replaced the rocker shafts did frequent oil changes and it ran well.
Just use a good filter, like a Wix. Don't use the extra long life or "synthetic" filters - those actually have *larger* holes so they don't clog up and can be used for 10,000 miles. "dirty oil is better than no oil" seems to be the thought process with the new stuff. Do a few changes with short-ish (500 to 1000 mile) intervals and see how it goes.
It's real common to have lots of burnt oil under the intake due to the exhaust crossover. I'm not as familiar with the pre-65 engines, but I expect the intake/crossover/turkey tray setup is pretty similar. Chunks will break loose from time to time. Seeing lots of silver or copper sparkle in the filter (say, if it looks like a disco ball threw up inside every fold) is a sign of a real bad problem. A tiny bit of sparkle (you notice a few specs here and there if you look hard) doesn't matter. Chunks of aluminum is bad. Chunks of oil crud is not.
The oil crud can clog the oil pickup. It's always nice to have an oil pressure gauge so you can tell if pressure drops off.
No chunks of aluminum, no big sparkles. Very few tiny specs, which sounds like it's ok for now. I will most likely change the oil and filter this month yet and report back.
Some excellent points above, made me remember my 64 HC 330 in a Cutlass convertible. The sludge was so bad the screen at the bottom of the fill tube was clogged and there was a mountain of crud under the intake. Pulled the heads did a thorough cleanup, replaced the rocker shafts did frequent oil changes and it ran well.
I'm hoping it doesn't get to the point of engine teardown, which I have never done before. In the future, this may be a job for a seasoned classic car shop.
Just for reference, how long was it between the prior oil change and the time the pictures were taken?
Prior to the pictures taken yesterday, it had been sometime in March, so maybe 2 months. Since the March oil change, I've driven the vehicle about 50 miles, if that. I've started the vehicle every once in a while, during the winter, which I probably shouldn't have done. I should have just let it sit until I was ready to warm it up, drive it, and change the oil. The spark plugs were very sooty, all 8 of them, which I've read can be due to running the vehicle not under load, not warming it up completely.
^^^ You're exactly right about that ... don't start the car up unless you can drive it and bring everything up to full operating temperature.
That said, I'd change the oil now with conventional oil and a decent filter like a NAPA Gold and monitor it. If it keeps getting really dirty, keep changing it. If it's staying clean, I'd change it again in 1000 miles or so, just to be on the safe side.
As mentioned dinosaur juice = dinosaur juice filter. Synthetic = synthetic filter.
That crud does not look catastrophic. Definitely keep an eye on it.
Get a mechanical oil gauge...dont use the plastic line use braided or copper with a vibration loop at the firewall.
If that engine has never been apart, 63 years of crud could be hiding. Remember the oil technology took a while to get good. Back in the day and even now If you didnt/dont pay attention to oil service the build up could be significant.
Pull a valve cover. If it comes off and leaves a loaf of bread the same shape as the valve cover you got sludge Exxon Valdez style.
I run this in all IC engines (after break in). I buy it in gallon jugs. Look it up it doesnt suck.
Some excellent points above, made me remember my 64 HC 330 in a Cutlass convertible. The sludge was so bad the screen at the bottom of the fill tube was clogged and there was a mountain of crud under the intake. Pulled the heads did a thorough cleanup, replaced the rocker shafts did frequent oil changes and it ran well.
I think you'll find that the 1964 330 engine was the "new generation" block that used a turkey tray. The 1964 394's had a "valley pan" that bolted to the the block to the casting section that holds the cam bearings. The bottom of the intake manifold did not contact engine oil.
I think the newer oils have more detergents that can clean years of sludge and crud build up over time. Keep using good oil filters and change oil as suggested. .
As mentioned dinosaur juice = dinosaur juice filter. Synthetic = synthetic filter.
That crud does not look catastrophic. Definitely keep an eye on it.
Get a mechanical oil gauge...dont use the plastic line use braided or copper with a vibration loop at the firewall.
If that engine has never been apart, 63 years of crud could be hiding. Remember the oil technology took a while to get good. Back in the day and even now If you didnt/dont pay attention to oil service the build up could be significant.
Pull a valve cover. If it comes off and leaves a loaf of bread the same shape as the valve cover you got sludge Exxon Valdez style.
I run this in all IC engines (after break in). I buy it in gallon jugs. Look it up it doesnt suck.
How involved is it to install an oil pressure gauge? I’ve never installed one. So it is best to order a quality gauge, and then some copper line separate?
'64 330's were the next gen; but, I believe they didn't use a turkey tray, rather a baffle that bolted down into the block/valley using a four piece intake gasket set. They also used rocker shafts not individual rocker arms with a pivot bridge.
How involved is it to install an oil pressure gauge? I’ve never installed one. So it is best to order a quality gauge, and then some copper line separate?
Fond the oil pressure sending unit, remove it and install the oil line in its place. I’m not sure where the oil sending unit is on the older engines, never messed with one.
I'd add the recommended amount of MMO to the oil to assist with the cleanup. As general practice do the oil changes on a warm to hot engine, just be reasonable with the temp to avoid burns.
Fond the oil pressure sending unit, remove it and install the oil line in its place. I’m not sure where the oil sending unit is on the older engines, never messed with one.
It's in the same place as usual - on the shelf behind the water pump.
Here are links to a variety of gauge line options:
How involved is it to install an oil pressure gauge? I’ve never installed one. So it is best to order a quality gauge, and then some copper line separate?
Have Stewart Wagner "green line" ( copper line ) in the 88 and oem oil lamp is also connected.
Fond the oil pressure sending unit, remove it and install the oil line in its place. I’m not sure where the oil sending unit is on the older engines, never messed with one.
It's on the right rear of the block.
Between the head and the bellhousing.
On all 394 engines.
May 8th, 2024, 01:23 PM
