Old Johnson 115hp: How do I know if it is a 2-stroke or 4-stroke?

[legendworks127]

I got an old Johnson 115 from off a project boat, but there seems to be conflicting information online as to whether it could possibly be a 2-stroke or 4-stroke. I'm trying to figure out if I need mixture or just straight gas to try to get this motor back running.

 

[racerone]

How old is old ??-----Do you see a timing belt or timing belt cover ?-----Post a picture or a model # -----I would say it is a 2 stroke motor with gas oil mix of 50:1.-----I suggest you read a manual or see some boating friends before you turn the key to start it.-----Outboards are often ruined by a lack of knowledge of how to operate them.

 

[legendworks127]

How old is old ??-----Do you see a timing belt or timing belt cover ?-----Post a picture or a model # -----I would say it is a 2 stroke motor with gas oil mix of 50:1.-----I suggest you read a manual or see some boating friends before you turn the key to start it.-----Outboards are often ruined by a lack of knowledge of how to operate them.

I think it's a 1975, but I do need to check to see if I can find the serial number once I get home.

 

[Chris1956]

gee what is the model number? Most OBs from that era were 2 cycle.

 

[racerone]

A 1975 model would be a 2 stroke !!---A V-4 with 2 carburetors in front of the engine.------Johnson marketed some rebadged 4 stroke models in the early 2000 model years.----They were built by SUZUKI.----Read some manuals before you start this 2 stroke engine.-----Or have it checked out by a shop and pay them to teach you.

 

[legendworks127]

A 1975 model would be a 2 stroke !!---A V-4 with 2 carburetors in front of the engine.------Johnson marketed some rebadged 4 stroke models in the early 2000 model years.----They were built by SUZUKI.----Read some manuals before you start this 2 stroke engine.-----Or have it checked out by a shop and pay them to teach you.

Would a 1975 be direct-injected, or a fuel-oil mix?

 

[racerone]

A 1975 model V-4 and 115 HP would run on a 50:1 gas oil mix.-----I strongly suggest you find an owners manual and read it 3X before trying to start this motor.-----Sounds like this is your first outboard motor.----Install a new water pump impeller.-----Do not run this motor without water supplied to the impeller.----Read some books !

 

[legendworks127]

gee what is the model number? Most OBs from that era were 2 cycle.

This is the motor serial number tag

 

[legendworks127]

A 1975 model V-4 and 115 HP would run on a 50:1 gas oil mix.-----I strongly suggest you find an owners manual and read it 3X before trying to start this motor.-----Sounds like this is your first outboard motor.----Install a new water pump impeller.-----Do not run this motor without water supplied to the impeller.----Read some books !

It's a 1975 electric start two-stroke. I've got an owner's manual, and I also had someone replace the water pump impeller.

 

[clemsonfor]

I got an old Johnson 115 from off a project boat, but there seems to be conflicting information online as to whether it could possibly be a 2-stroke or 4-stroke. I'm trying to figure out if I need mixture or just straight gas to try to get this motor back running.

Are we being punked here?

But if you have any doubt just mix the gas. Absolutely won't hurt a 4 stroke!

Two stroke will have a pre oil tank, a VRO pump unless it's too old for VRO and if that's the case it's 100% two stroke. A 4 stroke as said has a T belt also a filter on most probably, and also a dipstick and oil fill. It will also have a model and serial number plate, which should match the power head if it's original, on the bracket you can search online to see what it actually is.

 

[jimmbo]

Are we being punked here?

But if you have any doubt just mix the gas. Absolutely won't hurt a 4 stroke!

Two stroke will have a pre oil tank, a VRO pump unless it's too old for VRO and if that's the case it's 100% two stroke. A 4 stroke as said has a T belt also a filter on most probably, and also a dipstick and oil fill. It will also have a model and serial number plate, which should match the power head if it's original, on the bracket you can search online to see what it actually is.

The Oil Premixing System(VRO) was introduced in 1984, any OMC outboard prior to that will need to have oil added to the gas. In the case of a 115, 50:1 using a TCW-3 Oil.

 

[clemsonfor]

The Oil Premixing System(VRO) was introduced in 1984, any OMC outboard prior to that will need to have oil added to the gas. In the case of a 115, 50:1 using a TCW-3 Oil.

I thought the other day about my post and remembered it was VRO. They made the "spl" motors up into the 90s which were premix as well and didn't have the VRO systems.