Small engine oil.........

Dellbertt · Jun 4, 2008

Saw a small engine post and reminded me of this.

Several local people that I respect their mechanical knowledge have said that all small engines are supposed to run on mineral oil or non-detergent oil. Like lawn mowers, transfer pumps, etc. It"s supposed to make then run cooler and keep good compression.

I have always run straight 30wt. detergent with good luck.

Any thoughts?......

Bob · Jun 4, 2008

I use Mobil One synthetic in several OHV Briggs engines. It ended valve sticking and subsequent pushrod destruction.

Steven f/AZ · Jun 4, 2008

I've run everything from the cheapo WallyWorld oil to 15w-40 diesel oil to full synthetic in all of our lawn mowers, grain auger engines, etc. and have NEVER had a problem. Even have a worn-out generator full of 20w-50 so it doesn't burn so much. Never a problem in 15 years so far, I'm sure Dad has been doing it that way for all of his 40 years or so of farming. I know darn well there hasn't ever been any non-detergent junk oil on the farm.

45 JDB · Jun 4, 2008

I have used Mobil 1 5W-30 Synthetic in all my samall engines for years and have NEVER had a problem. Non-detergent oils lead to deposits and gunk things up. The cleaner the engine the longer it will last.

MikeinKy · Jun 4, 2008

The important thing with small engines, is keep them full because the oil acts as a coolant.

JT · Jun 4, 2008

small engines need a detergant oil.

Wayne from MN · Jun 4, 2008

Non-detergent oil is really only good for a non-combustion type situation; an air compressor for example.
Do the manufacturers put non-detergent oil in at the factory? I do not know of any.
Today's oils are far superior to yesteryears so following the original owner's manual on an antique can be misleading as to what oil to use.

Bob M · Jun 4, 2008

Ummm…I think your “experts” are confused!

Running non-detergent oil in a small engine (or any 4 stroke engine) crankcase causes sludge to accumulate. Sludge buildup in turn shortens engine life.

---

A couple possible explanations for the confusion:

1 - Some small engine manufacturers recommend using straight weight detergent oil (eg. SAE 30) over multi-viscosity oils (like 10W-30). Reason: Viscosity index improver additives in multi-vis oils tend to break down under the high temperatures of small, air cooled engines resulting in reduction of the oil’s lubricating ability. Single weight oils do not experience this breakdown.

2 - Before dedicated “2 stroke” oils were developed, 2 stroke engine manufacturers recommended straight, non-detergent oil mixed with the fuel. This is because additives in detergent oil (metallic salts, etc) when burned leave conductive deposits on spark plug electrodes. And the deposits cause plugs to foul/misfire.

---

Bottom line: Forget the “experts” at the coffee shop…..follow the engine mfr’s oil recommendations!

IH2444 · Jun 4, 2008

The official Briggs and Stratton oil is a detergent oil....

El Toro · Jun 4, 2008

I have used 30wt detergent for years in these air cooled engines. No problems with engines. Hal

IH2444 · Jun 4, 2008

Some of the Kohlers with hydraulic lifters have lifter problems if you run too thick oil in them.
I have been running 10w40 synthetic in all my small engines for a few years. Only costs a few more bucks a year and the syn stuff handles the heat better.

Tom Fleming · Jun 4, 2008

You want to use a detergent oil. period. Everyone has their "pet" oil, SAE 30, 15W-40, 5W-30, and on and on. Non-detergent oil is for compressors and hydraulics (in some cases). I believe my Cub manual says to use non-detergent SAE20 in the touch control unit (could be wrong here, and the manual is not close by).

One thing that is more important than which oil you use, is changing it regularly, and the filter.

Myself, I use detergent SAE 30, straight weight in the summer, and SAE 10 straight weight in the winter. However, any quality detergent oil, changed on a regular basis is what is important. And, Oh My God, when in a pince, I have mixed multi-vis with straight weight when a tractor was low. Not enough oil is also MUCH worse than topping off with a different weight or type of oil.

IMHO.

Small engine oil.........

Dellbertt

Member

Bob

Well-known Member

Steven f/AZ

Well-known Member

45 JDB

Member

MikeinKy

Well-known Member

JT

Well-known Member

Wayne from MN

Member

Bob M

Well-known Member

IH2444

Well-known Member

El Toro

Well-known Member

IH2444

Well-known Member

Tom Fleming

Well-known Member

Similar threads