96TL
Well-known member
Me and Dale were talking about why the F250 requires premium fuel to run, and what would happen if you ran regular. I gave Yamaha a call to find out some more info. I'll post it here for those interested.
The rep I spoke with said it actually does not need premium fuel (93). It needs a minimum of 89, which is mid-grade, and usually the lowest grade found at marinas (which is true in my area). Its a high compression motor, tuned specifically to 89, and anything lower than 89 will retard the timing and MAY cause pinging or knocking and excessive carbon build-up. The F250 has a knock sensor, and will change the mapping to prevent engine damage, but you will lose some HP in the process. He didn’t know how much. Regardless, they still do not recommend running 87 at all. Just not worth the risk.
I dont think its really a big deal. Most high performance car engines today demand premium fuel as well (mine does). That’s what the motor was tuned for. The F250 is (was) Yamaha’s flagship motor. I’m sure they wanted to squeeze every drop of HP out of it as possible. I would probably save just $20.00 or so per tank if I went to 87 anyway. I only fill up 3 times per season. Not a big deal.
Also, if you're missing your owner's manual, you can view them online here.
http://www.yamaha-motor.com/outboard/se ... s=outboard
Dom
The rep I spoke with said it actually does not need premium fuel (93). It needs a minimum of 89, which is mid-grade, and usually the lowest grade found at marinas (which is true in my area). Its a high compression motor, tuned specifically to 89, and anything lower than 89 will retard the timing and MAY cause pinging or knocking and excessive carbon build-up. The F250 has a knock sensor, and will change the mapping to prevent engine damage, but you will lose some HP in the process. He didn’t know how much. Regardless, they still do not recommend running 87 at all. Just not worth the risk.
I dont think its really a big deal. Most high performance car engines today demand premium fuel as well (mine does). That’s what the motor was tuned for. The F250 is (was) Yamaha’s flagship motor. I’m sure they wanted to squeeze every drop of HP out of it as possible. I would probably save just $20.00 or so per tank if I went to 87 anyway. I only fill up 3 times per season. Not a big deal.
Also, if you're missing your owner's manual, you can view them online here.
http://www.yamaha-motor.com/outboard/se ... s=outboard
Dom