I recently reserected an old (I'm not sure what year it is) Yamaha YFM80 that was left to die in my In-Laws barn. I stripped it down and got it running great. When I took the bowel off the carb the main jet and arieator fell out in my hand. The positive & negative cables off the battery were all chewed up from some type of rodent.

Anyway, to the question. It was idling great. I hadn't changed the oil in it so I went ahead and drained out around a quart of oil. I didn't have any YamaLube or a manual to recommend a proper oil. I used a 30 weight with no "energy conserving" crap in it.

Anyway, it doesn't want to idle like it did before. It seems to be more cold blooded than before. You have to choke it up and let it warm up before it want to idle on it's own for any length of time. I am going to get me some YamaLube and change it again, but what gives?? Would oil make that kind of a difference??

I feel stupid asking this because I just totally overhauled my Raptor and it's runing like (as my friends say) a Raped Ape!! Then this little runt is being tempermental on me!!

I think it must be the oil, but what are your thoughts??

Thanks in advance

GregV

 

Hey Greg,

The oil weight and type does do this on small displacement engines, but I haven't heard a case so bad as the one you describe.

Are you sure you aren't forgetting something that you did at that time to cause it?? Maybe just coincedence??

By the way....how much oil did you put in there?? The engine only holds about 3/4 of a quart.

Patrick

 

If this is a 2-stroke, GM ATF works best!

 

The only thing else I did was pick up the back end of it to drain all the old oil out. I thought maybe I stuck the float or something so I used the caveman approach and picked up the front end and dropped it twice to free it, if that was the case. Like I was saying, it still runs good, it's just not as quick to idle like it was. I had better check on the amount of oil, because I'm pretty sure I am around a whole quart.

Thanks Guys.

P.S. it is a 4-stroke 2fat4moto ( Great name by the way [img]i/expressions/face-icon-small-smile.gif[/img] )

 

Oh, no need for GM ATF!