Yamaha outboard 4-stroke Engines

[ERR446]

I am considering a new 115 hp or 200hp(to be introduced in July 2002) Yamaha EFI 4-stroke. Can someone enlighten me about the timing chain/belt design and if it is reasonable to expect it to be a problem? GRIZ1000@aol.com

 

[ERR446]

Re: Yamaha outboard 4-stroke Engines

To be more specific, my question is if the timing belt breaks can the pistons colide with the valves?

 

[MIKE F]

Re: Yamaha outboard 4-stroke Engines

ERR446 I don't have an answer for you (doesn't seem like anybody else does either)<br /> <br />I was wondering when you originally posted this how you could consider a 115 or 200 for the same boat. Seems like there would be quite a difference in cost- performance etc.

 

[ERR446]

Re: Yamaha outboard 4-stroke Engines

The new boat I am considering is rated for a 200hp Max outboard. I don't want to buy more power than I need to travel between fresh water fishing spots (top speed not all that important), do a little trolling at low speed, and pull water skiers (some beginners who want to get up quickly). Thus I am considering a 150 hp and the max rated hp. Maybe you can help. The hull dry weight is 2300#, deep V, 20 feet by 8 1/2 foot beam.

 

[MIKE F]

Re: Yamaha outboard 4-stroke Engines

ERR446 I answered your post on the Trailer Boat Magazine web site. My latest post to you was to check out the DFI engines as an alternative to 4 strokes.Again I'll say that the 115HP is probably not enough - particularly if it's a four stroke.I think with a boat rated for 200HP a 150HP or a 175HP would be fine for overall performance.<br />I knew this question seemed familiar.

 

[ERR446]

Re: Yamaha outboard 4-stroke Engines

Thanks for your Trailer boat forum and this response. After you comments on TB I started considering a 150hp 2-stroke. Think I'll probably by a carb 6-cylinder from Mercury or Yahama.

 

[MIKE F]

Re: Yamaha outboard 4-stroke Engines

Sounds like a winner.Hp should be fine and definitely cheaper than DFI or 4 stroke.I'd like a bigger engine but don't use the boat enough to justify replacing what I have.If I were to change I might go for a EFI. or not.

 

[seahorse5]

Re: Yamaha outboard 4-stroke Engines

To answer your first question, the 115 valves will hit the piston if the timing belt jumps or breaks. The 200-225 motors have notches in the pistons and the factory says all 24 valves won't hit.

 

[ERR446]

Re: Yamaha outboard 4-stroke Engines

Thanks, this was the answer I was wondering about.