Evinrude 48 SPL Overheading

papakevin

Petty Officer 2nd Class
Joined
Apr 10, 2005
Messages
103
I just saw another post on an overheating with a Evinrude, but I think mine is a little different.<br /><br />Went to the lake today with my 16' Skeeter, wife, and son. For the first time, I put them both in a tube behind the boat, and pulled them around the lake for a while. The boat took a very long time to get on plane, but I'm assuming this is because of the weight in the tube behind the boat. (Right?)<br /><br />After running for about an hour, I went to idle to pull them in, and a buzzer went off in my control box, which I'm assuming was a overheating buzzer. I looked back at my motor and noticed the water was coming out of the motor as it should, but it wasn't as strong as it normally is. <br /><br />Since I was running it hard, I let it set for a few minutes and started it back up. Buzzer was on for about 15 seconds following the start-up, but went off when I gave the motor some gas and got it going in some water. After about 15-20 minutes, the buzzer went off again, so I shut it down. Let it cool off, then started it back up, and brought it in at about 1/4 throttle with no problems at all.<br /><br />When I pulled the boat out, I noticed some "lakeweed" (like seaweed, but in a lake) about the hydorfoil, so I'm thinking I may have sucked something into the motor and gunked up the circulation. Also when I first put the boat in, it drifted into a shallow area near the ramp and grounded the fin while it was running, so some mud and sand could have gotten into it.<br /><br />Now to my questions....(sorry for the long story).<br /><br />1) I know I need to get a manual for this motor. Any recommendations on what is the best one to get? Is there a location on the internet where I can pay and download a manual? I have a 1988 Evinrude 48 SPL.<br /><br />2) How can I go about cleaning the water intake in the event something did get sucked up? Do you think running it hard with a tube behind it could have caused the impeller to start and fail, or since some water is still coming out, is a clog more likely?<br /><br />3) Is there anything I can do to get the boat on plane faster (besides buying a bigger motor or going on a diet)? The motor already has a Stingray Hydrofoil. The prop has a few small nicks, but I don't know if this causes a big drop in performance.<br /><br />4) The boat idles rough and smokes on start-up. Could my plugs be fouled? Is there a brand of plugs which is highly recommended for this motor? <br /><br />Thanks again for any and all help.
 

papakevin

Petty Officer 2nd Class
Joined
Apr 10, 2005
Messages
103
Re: Evinrude 48 SPL Overheading

Any and all help is welcome and appreciated.
 
D

DJ

Guest
Re: Evinrude 48 SPL Overheading

1. Manuals are available here on iboats. See manual link at bottom left corner of page. Either the Seloc or Clymers are OK for routine maintenance.<br /><br />2. If you do not know when the last time the water pump impeller was changed, you're overdue.<br /><br />3. Without knowing what your wide open throttle rpm's are, you're guessing. That engine should run at least 5500 with an average load at WOT. A "slightly" dinged prop can seriously hurt performance. Before you buy another one, get a tachometer.<br /><br />4. Use CHAMPION plugs only.<br /><br />Because this engine has been a working so hard, you may want to do this (decarb). See link.<br /><br /> http://www.iboats.com/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=36;t=000016
 

papakevin

Petty Officer 2nd Class
Joined
Apr 10, 2005
Messages
103
Re: Evinrude 48 SPL Overheading

A manual is on order and on the way. Thanks DJ.<br /><br />I'm probably due for an impeller change. Any good information I can get on changing it out before the manual gets here? I'd like to be back on the lake this weekend. Also, if I did suck up some junk, any magic way to clean it out?<br /><br />Any suggestions on what type of tach I should get? I'm not looking for anything fancy. I believe the controller has a connection for a tach.<br /><br />I'll get the Champion plugs. Gap at 30, right?<br /><br />Thanks again! Keep any and all information coming!
 

Mark42

Fleet Admiral
Joined
Oct 8, 2003
Messages
9,334
Re: Evinrude 48 SPL Overheading

I took out my thermostat tonight and there was a little bit of gritty junk stuck in it. Looked like sand and seeweed goo. I plan to run it tomorrow on the hose without the thermostat just to help flush it out. Might even take off the thermostat cover for a moment to help blow stuff out of the head passages. <br /><br />I would not doubt for one minute that lake grasses and weeds clogged the intake. When you shut down and tilt the motor up to inspect, I think it falls off giving you the false impression that nothing was clogging the intake.<br /><br />My 93 omc manual says gap at 0.030". plug is Champion QL78YC.<br /><br />It could also be that your thermostat is failing by not fully opening. That would make it run OK most of the time, but get overheated under load like towing. I don't think the tow load stresses the water pump. Stress on the pump is determined by the motor rpm, not the load the motor is hauling.
 

papakevin

Petty Officer 2nd Class
Joined
Apr 10, 2005
Messages
103
Re: Evinrude 48 SPL Overheading

Excellent, thanks Mark42. Looks like I have a project for late Friday night. <br /><br />Hopefully, I'll be back in the water on Saturday. Thanks again.<br /><br />By the way, any suggestions on where I can pick up a good tach for my motor?
 
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