Non detergent motor oil for old engine

I had no idea that nearly all modern motor oils contain detergent.

I am worried because I am preparing to run an 80 year old engine.

I am worried that if i use a conventional motor oil with the usual detergent content that it can release any engine deposits and allow them to circulate in the engine and clog something up.

I would rather go with a non-detergent oil such as valvoline with added Marvel Mystery oil to slowly work away with any deposits.

I have already dropped the oil pan and it was not that dirty.

Does anyone have an experience in these areas.....Any help will be greatly appreciated.

Practically all oil today is detergent oil. You can still get non detergent but you have to look for it and most auto parts places don't stock it.

If the engine is clean inside there is no harm in using detergent oil, and some benefit. As you have cleaned the oil pan and inspected the oil pump and screen it should be ok.

Detergent oil was introduced in 1951. If the engine was rebuilt in the last 60 years there is a good chance it was run on detergent oil.

It might help to tell us what model, make and year. Unless you think all engine are the same.

There were various kinds of lubrication systems in 1935 including splash and pressure fed, most engines used poured babbit bearings, but Chrysler introduced insert bearings the year before.

If we knew what kind of engine a specialist in that make, might have specific recommendations.

Current non-detergent oils will state they are non-detergent on the label. If, not it is detergent. The oil additive called "detergent" is not what we normally think of as a detergent. It is a chemical compound that keeps contaminants too small to be trapped in the oil filter, like carbon, water, etc., in suspension in the oil to keep them from settling out and forming sludge. I am skeptical that detergent oil will loosen existing sludge and keep it in suspension.

If you have inspected the oilpan and find no significant sludge then it should not matter what type oil you use as long as you change the oil and filter at regular intervals. After 5,000 miles or so of normal use motor oil additives start to loose their effectiveness so contaminants will start to settle out and begin forming sludge.

Practically all oil today is detergent oil. You can still get non detergent but you have to look for it and most auto parts places don't stock it.

If the engine is clean inside there is no harm in using detergent oil, and some benefit. As you have cleaned the oil pan and inspected the oil pump and screen it should be ok.

Detergent oil was introduced in 1951. If the engine was rebuilt in the last 60 years there is a good chance it was run on detergent oil.

It might help to tell us what model, make and year. Unless you think all engine are the same.

There were various kinds of lubrication systems in 1935 including splash and pressure fed, most engines used poured babbit bearings, but Chrysler introduced insert bearings the year before.

If we knew what kind of engine a specialist in that make, might have specific recommendations.

1933 ford model b

the pan actually had an inch of particles that looked like sand and scoped out like sand, not greasy or slick as heavy crude oil.

It probably was sand, dirt and sludge deposited there as a result of using non detergent oil. There used to be a theory that non detergent oil let the dirt and sludge settle out and get caked on the inside of the engine, where it did not get in the bearings.

Better to use detergent oil and an oil filter. There are add on oil filters that can be adapted to your motor. A bypass filter actually filters finer particles than the new full flow, the bypass is what you need.

When your car was made they wanted you to change the oil every 1000 miles to get the dirt and sludge out. With a good filter, detergent oil, and driving on good paved roads this can be extended to 2000 or 3000 miles. Filters will last 5000 or more.

I have to reply. My dad swore a Richfield mechanic ruined the engine in his 53 Olds by using detergent oil. Prior to that non detergent was used. I remember as a kid working for Texaco in the 60's their non detergent oil came in a red and white can and it did not have the nave Havoline...

1953 Olds had an OHV V8 with hydraulic lifters. The manufacturer recommended detergent oil. Running the engine on non detergent was dangerous to the health of the engine.

Tractor Supply sells non detergent oil.

1953 Olds had an OHV V8 with hydraulic lifters. The manufacturer recommended detergent oil. Running the engine on non detergent was dangerous to the health of the engine.

evidently the guy that owned the car before my dad did not use detergent and did not real his manual!

Kendall racing oil is a straight grade variant if that's also what you seek. Sold as "Nitro 40" or Nitro 50" it's a great alternative to old engines seeking straight grades and different additive packages. While I may get lambasted for this, it's a freaking Ford 4 cyl engine! It'll run on anything and live through volumes of abuse, NEVER needs hardened valve inserts, and frankly doesn't even need zinc (ZDDP) in the oil. Visit www.fordbarn.com and scam around on the Model A pages regarding oils and ZDDP. An eye opener to be sure, and 'ol Henry was very proud of his metallurgy knowledge. Most Ford owners are too. Good luck and don't over think it. Also, shameless plug here, I have a 1933 1 bbl manifold in above average condition. It does have the update done to the rear that some want and some don't. PM me here or email me at highlander809@gmail.com if you might want it.

check NAPA - I believe they carry a house brand non-detergent oil

Don't be surprised if it's more expensive than detergent oils... it was at Advance Auto when I went after some a few months back.