View Full Version : Premium vs. Regular Gas
After filling my tank yesterday for the first time this year the price for premium gas was 92 cents Canadian. The temptation is there. Should I try running regular gas? I am running a '95 Merc. 40 hp. with oil injection. Is anybody out there running regular? Will I damage my motor? I have never ever put a drop of anything but premium in it and it runs like a top, but these prices are going to have a definite effect on my fishing this year. OUCH!!!
I have a 2000 Merc 150 EFI and my manual says to use regular. Premium is only needed in hi performance engines. What does your manual say to use?
MarkG
05-27-2001, 07:57 PM
Had been running premium for years in my 90HP Merc,ran great.,but when they started "reformulating" and "oxygenating" etc. it didnt run nearly as well. I switched to midgrade and regular and ran much better than on reformulated premiums.I dont run premium in anything anymore.
steve(IL)
05-28-2001, 12:09 PM
Contrary to what you'd think, it's my understanding that running premium can actually do your motor a disservice..something to do with oxygenates. Check your owners manual or talk to a factory rep.
Driftr
05-28-2001, 01:11 PM
Food for thought! With the prices the way they are Premium fuel will sit alot longer too. Regular will be the freshest.
Driftr
T-Mac
05-28-2001, 03:46 PM
Run regular.
I know what the manual says, but I've had several shop techs and one factory rep from Merc tell me run89 octane, no more, no less. 89 still exceeds the min if it is from a source that has older fuel. Yet, it doesn't have all the extra crap in it premium does. In the old days, I saw a torn down engine that had nothing but premium in it at around 750 hours. It was like new. It was torn down do to over rev from a sheared gear case. I've seen lease motors torn down with problems that you know got the lowest grade fuel. They were quite filthy. Another thing I found and was told by the same folks is to run the engine tunner regularly.