1993 Yamaha 40hp mlhr

Hey everyone,
In the process of trying to find a bigger motor for my lunker v16, I found a 40 hp Yamaha from a somewhat local dealer, was wondering if anybody had any input or previous knowledge good or bad about the motor. It’s a 1993 Yamaha 40hp that appears to be manual start only and in the one and only picture I have of it right now it looks to be in good cosmetic shape.Any advice or things to look for are greatly appreciated

I had a Yamaha 40 and it was a awesome motor. Started great, trolled great,and was decent on fuel. I had a Reed go in 2015 which took out the top end. But it was owned buy a guide before I bought it and I put a ton of hours on it myself.

Have a compression test done on the cylinders. Obviously being a 93, there will be wear on the motor, but that will give you a realistic understanding of the rings/cylinder condition. #1 you want to see that they are wearing evenly #2 how far below factory spec it is. I have a 91 ProV150 that is worn…..heavily worn!!! and it still fires right up and runs like a stud in the Kentucky derby

I see it says Precision blend on it, what in a nutshell does that stand for? Also about what should the compression be on this motor?

Precision Blend was Yamaha’s oil injection system. So, it’s a 2-stroke motor with oil injection, meaning you don’t have to premix oil in the gas (this is assuming that the previous owner didn’t bypass the system). From what I have read, the Precision Blend system was quite reliable.

I assume it has an oil pump and it blends your oil/gas at the engine – no manual mixing

I don’t know the exact specs for that engine. Typically 2stroke engines are around 115psi. (varies 100 – 130ish) below 100 is showing wear. more than 10% difference between cylinders is uneven wear and bigger issues

Thanks everyone, very helpful info!

These were very good outboards and if you travel there are still many lodges and resorts that have a whole fleet of 2 stroke Yamahas that have run for decades in salt water and are still going strong.

Precision Blend is Yamaha’s oil injection system.

If the previous owner has disconnected it, run away. It was a very good system and there should have been no need to mess with it, so it would make me wonder what other hacking the previous owner did to the outboard.

Compression from the factory was 125. After break in this would most likely be 120. For the age of the engine, anything 100 or above I would say is acceptable, but +1 on Randy’s comment. Variance between cylinders is a key indicator of possible issues.

Ive got a 93′ 60hp. It has been a great motor. The only thing ever done to it was put in a new head gasket and of course water pumps.

I have a 40hp Yamaha model elrr can anyone tell me the part# for the throttle cable! Any help would be appreciated!