48hp evinrude

[mmart]

hey guys, let me run this by some of you guys. 48 evinrude m#e48esleim, s#g02980685. problem, runs great at idle but when you rev it past half throttle it starts surging. figured carbs clogged at high speed circuit. removed carbs cleaned (soaked in carb cleaner overnight). re-assambled and installed. the carbs were not that bad. dumped old fuel for new, changed the plugs (NGK equivilent) ran motor but still surges. here is the bizzare part, I have heard of this happening but not to me. the eng started reving out like there was no rev limiter. turned the key off, still kept reving, pulled the tether, still reving, pulled the spark plug caps off of the plugs, still reving out. I unhooked the fuel line and it stop after a min. or so. all the time it was hooked up on a flush. hooked everythig back up and it ran fine at low and high speed for about 10 mins then it started suging again at half to full throttle, now I am thinking that it may be an electrical issue, did a search to see if anyone has had this issue before but found nothing. any help would be greatly appreciated

 

[Goodoleboy]

Re: 48hp evinrude

Your mighty lucky she didnt blow up. A two stroke can do this when over reved with no load on engine.<br /><br />NEVER...go above idel while runnin on the muffs. The reason it keeps on reving after all plug wires are removed is because of carbon hot spots in heads or tops of pistons.<br /><br />Engine needs to be decarbed. You can read up on how to do this in FAQs.<br /><br />And I would strongly recomend you get those NGK plugs out of that engine before you do any thing else. Use proper rated champions... ONLY.<br /><br />I wouldnt try running this engine until you do a good decarb on it.<br /><br />Next time you have a "run away" she just mite hurt somebody real bad.<br /><br />Good Luck!

 

[MCM]

Re: 48hp evinrude

Hi, 4 possible causes:<br /><br />Open lead (key switch to power pack)<br /><br />Faulty key switch<br /><br />Incorrect wiring harness (probably not if original)<br /><br />Faulty power pack<br /><br />Maybe others as well but these are probably the most likely.<br /><br />Mike

 

[mmart]

Re: 48hp evinrude

goodolboy, I thought the ngk plugs might be an issuue, i will switch back to champions, will de-carbonizing the motor help with the surging, or just remove the hot spots (carbon in the motor) I understood what caused the reving up part. after buying a clymers manual and reading the troubleshooting section, I thought it might be the power pack. I will test that area next. thanks for your help

 

[Goodoleboy]

Re: 48hp evinrude

Welcome to forum.<br /><br />Surgeing is almost always caused by faulty fuel pump. However I wouldnt change it until you put in the water at full power. Then if it continues to surge then rebuild or replace fuel pump.<br /><br />I would do a link and sync. on this motor. Check WOT timeing as well as idle timeing.<br /><br />Do all of this after first decarbing engine. You can use those NGK plugs to decarb with then put in new champions as recomended by you manual.<br /> <br />Decarb at idle ONLY. That sucker will blow if you try to rev it on the muffs.<br /><br />Your foolin with a stick of dynomite!.. Keeper down. <br />If Iam scarein ya...good..thats what Iam tryin to do.<br /><br />If it gets away from you ....disconnect the fuel line instantly...then jerk plug wires off and back away as quick as possible.<br /><br />Good luck!

 

[mmart]

Re: 48hp evinrude

hey goodolboy, well you are not scaring me, but I am a very cautios person, and I appreciate you're candor. I will heed you're warning.I am starting to dabble in outboards. I am a motorcycle/ pwc tech for over 15 years, but these outboards I am finding out are a whole different animal. I am very glad I found this forum, I've learned alot by reading many of the posts. I really appreciate your help.

 

[Goodoleboy]

Re: 48hp evinrude

Good Iam glad you are machanic and of the cautios nature.<br /><br />I knew I was going a bit over the top so to speak. But also realiseing that many other people new to outboards reads these post also. <br /><br />So if it helps somebody then thats good...!<br /><br />Welt my work is do here...off to save the rest of the world now....!<br /><br />Geese...Iam sickning!..Grin!<br /><br />Good Luck!