150 evinrude lost power

[kelly70394]

i'm not much of a boat person, so bear with me.<br /><br />I bought a 1994 18' Astro bass boat with a 1993 150 Evinrude XP not oil injected. I test drove it and it operated very nice. Ran at 54.9mph. The previous told me that the motor was serviced recently. I could see some parts still has part # stickers on them and they look brand new.<br /><br />I took it out on two occasions and it ran great. Three days ago, I launched the boat, and started the motor. It ran knida rough, but I assumed it did that because it was cold.<br /><br />Once I believed it was warmed up, I accelerated. While traveling down the bayou, I noticed the motor appeared to be missing(I guess. Did like a car does when it misses)<br /><br />Then the RPM gauge started to go up and down from 3300rpm-? to 1000 rpm. Then the motor died. I started it back up, and tried it again. It lost power and died.<br /><br />Started it again and let it idle. It ran fine to me. So I placed it in gear and accelerated slowly. The motor vibrated and it would not come off the plane. Placed it back on idle, ran fine. I got escourted back by my fishing buddy. While enroute to the marina, I tried placed it in full throttle, it vibrated, and it appeared to be bogging down as if I had something around the prop. Of course they didn't. <br /><br />I explained this to a boat mechanic and he told me it maybe the powerpack. Any one else has any idea's? Previous owner told me to mix 1 qaurt of oil to every six gallons, which i do

 

[andy6374]

Re: 150 evinrude lost power

Start with the basics. Check the compression and then for spark. <br /><br />Then move on to fuel. Start with the tank and work your way to the carbs, checking the primer bulb, fuel pump, fuel lines, water separator along the way.

 

[Walker]

Re: 150 evinrude lost power

Check for overheating too. Sounds like maybe the SLOW system kicked in.

 

[alden135]

Re: 150 evinrude lost power

Originally posted by kelly70394:<br /> Previous owner told me to mix 1 qaurt of oil to every six gallons, which i do

You're running twice the recommended oil.<br /><br />50:1 is 16 oz oil to 6 gal gas

 

[DHPMARINE]

Re: 150 evinrude lost power

when you test spark and compression,next step should be a fuel sample,looking for dirt or water. If these pass muster,then you can go deeper.<br />Your engine can handle the double oil (providing it's TCW 3 ),but cut back to eliminate sludge and other buildup.<br /><br />DHP

 

[alden135]

Re: 150 evinrude lost power

I wasn't making a diagnosis, merely pointing out the incorrect ratio.<br /><br />Diagnostics are what you guys are for

 

[kelly70394]

Re: 150 evinrude lost power

I haven't seen a fuel/water separator nor any filtration, so I'm guessing that caused the problem? <br /><br />Dealing with the oil mixture, thx for the infomation. Also, the Overheat alram came on while I babied the boat to the marina, but it was running very slowly @ full throttle. The water pump works fine, the engine "pees".

 

[OBJ]

Re: 150 evinrude lost power

The engine has two thermostats....one for each head. If one fails closed, you will get the overheat alarm even though the engine pees' OK. I would investigate the alarm a little more along with a set of compression readings and spark tests.<br /><br />Most of these engines will have an inline fuel filter somewhere on the port side of the engine. Just follow the fuel nipple hose inside the pan and you should run into it. If there is none, it would be wise to have one installed.