Full synthetic marine gear lubricant?

thinkxingu · 11-21-2022, 05:42 AM

Why? A 5 quart jug of Mobile 1 is under $30 at Walmart and will last a few seasons.

Sent from my SM-G990U1 using Tapatalk

SAB1 · 11-21-2022, 08:05 PM

I’m by no means a wrench but gear oil is not going to have additives like detergents and dispersants to combat byproducts from combustion.

Loub52 · 11-21-2022, 08:15 PM

Quote:

Originally Posted by thinkxingu

Why? A 5 quart jug of Mobile 1 is under $30 at Walmart and will last a few seasons.

Sent from my SM-G990U1 using Tapatalk

The gear oil was recommended as a suitable alternative by a hardware clerk. They had no fully synthetic 5/30 engine oil available. The more I thought about the suggestion as I was about to break the seal on the container and finish changing the oil, I thought it would be better to do some more checking.

Charlie T · 11-21-2022, 10:38 PM

Quote:

Originally Posted by Loub52

The gear oil was recommended as a suitable alternative by a hardware clerk. They had no fully synthetic 5/30 engine oil available. The more I thought about the suggestion as I was about to break the seal on the container and finish changing the oil, I thought it would be better to do some more checking.

Let me start by saying I'm a huge proponent of Synthetic oil, I use it in all my engines. BUT, don't blindly substitute Synthetic for Dyno oil in small engines or older engines without full knowledge of what you are doing.

Virtually all modern Auto engines use a Roller lifter on the camshaft, this type of lifter reduces internal friction and allows for more aggressive valve lift events which can equal more power, better emissions and better mileage. Older engines and most small engines like a snowblower have an old style "Flat Tappet" cam/lifter. The flat tappet engines require a zinc additive known as ZDDP to combat excessive wear between the lifters and cam. As modern engines, with roller lifters don't suffer from this wear issue, most, not all synthetic oils don't have the ZDDP additive. Use of this type of oil without ZDDP in a flat tappet engine could result in excessive valve train wear and engine failure. There are some synthetics that specifically include the ZDDP needed, I know of a few specific Mobil 1 formulations that have it. The V twin oil designed for Harley's is one of them. Use caution when straying on oil types in an engine, it's easy to do more harm than good.

YMMV of course.

Charlie T

Poor Richard · 11-23-2022, 05:56 PM

Quote:

Originally Posted by Loub52

The gear oil was recommended as a suitable alternative by a hardware clerk.

I would be speaking with the hardware store clerk's manager about the total crap advice their employee is giving out but that's just me.

8gv · 11-23-2022, 08:20 PM

One can run an internal combustion engine with practically any lubricant in its crankcase.

The question is, how long will it run?

During my formative years I acquired a lawnmower engine that no longer had a lawnmower attached.

For reasons only understandable only to a young teen, I performed a "test" on it.

The crankcase oil was replaced with Wesson cooking oil.

The empty fuel tank received a quantity of Coleman camp stove fuel.

I wired the throttle WFO and started her up.

The engine droned on for several minutes while filling the driveway with plenty of noise and the aroma of fried food.

It got boring so I went back inside the house.

A few moments later there was a loud clank that turned my head in time to see the engine cartwheel across the driveway.

The conclusion I drew from the test was not to run an engine on Wesson oil or maybe Coleman fuel but definitely not both!

TiltonBB · 11-24-2022, 08:57 AM

When I was young the men (3 brothers) at the local gas station convinced me that I needed to flush out the engine on my first car with a 50/50 combination of motor oil and kerosene. In an hour or so of driving around that engine was junk.

It became a learning experience. I went to the local car junkyard and bought a used engine and swapped the engines out in my father's garage.

I should have known better than to listen to the gas station guys. They were the same people who convinced me that I needed to drain the air and reinflate the tires on my bicycle because old air loses it's bounce. Hey, I was only seven years old. I thought adults knew stuff!

11-21-2022, 05:42 AM	#1
thinkxingu Senior Member Join Date: Jul 2014 Posts: 6,323 Thanks: 1,174 Thanked 2,096 Times in 1,297 Posts	Why? A 5 quart jug of Mobile 1 is under $30 at Walmart and will last a few seasons. Sent from my SM-G990U1 using Tapatalk

11-21-2022, 08:05 PM	#2
SAB1 Senior Member Join Date: Feb 2012 Location: Tuftonboro Posts: 1,243 Thanks: 192 Thanked 329 Times in 239 Posts	I’m by no means a wrench but gear oil is not going to have additives like detergents and dispersants to combat byproducts from combustion.

The Following User Says Thank You to SAB1 For This Useful Post:
Loub52 (11-21-2022)

The Following 2 Users Say Thank You to Charlie T For This Useful Post:
Loub52 (11-22-2022), Poor Richard (11-23-2022)

11-23-2022, 08:20 PM	#6
8gv Senior Member Join Date: Jan 2012 Posts: 2,115 Thanks: 64 Thanked 749 Times in 483 Posts	One can run an internal combustion engine with practically any lubricant in its crankcase. The question is, how long will it run? During my formative years I acquired a lawnmower engine that no longer had a lawnmower attached. For reasons only understandable only to a young teen, I performed a "test" on it. The crankcase oil was replaced with Wesson cooking oil. The empty fuel tank received a quantity of Coleman camp stove fuel. I wired the throttle WFO and started her up. The engine droned on for several minutes while filling the driveway with plenty of noise and the aroma of fried food. It got boring so I went back inside the house. A few moments later there was a loud clank that turned my head in time to see the engine cartwheel across the driveway. The conclusion I drew from the test was not to run an engine on Wesson oil or maybe Coleman fuel but definitely not both!

11-24-2022, 08:57 AM	#7
TiltonBB Senior Member Join Date: Feb 2005 Location: Gilford, NH and Florida Posts: 3,026 Thanks: 706 Thanked 2,208 Times in 940 Posts	When I was young the men (3 brothers) at the local gas station convinced me that I needed to flush out the engine on my first car with a 50/50 combination of motor oil and kerosene. In an hour or so of driving around that engine was junk. It became a learning experience. I went to the local car junkyard and bought a used engine and swapped the engines out in my father's garage. I should have known better than to listen to the gas station guys. They were the same people who convinced me that I needed to drain the air and reinflate the tires on my bicycle because old air loses it's bounce. Hey, I was only seven years old. I thought adults knew stuff!