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1965 18hp Evinrude Fastwin issues

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petefrommaine

New member
Hey Guys,

New to the forum so hey ya'll. I got this motor on the trade for a running 6 horse and I have to say im a little dissapointed. Was told it wouldnt start and was just a carb issue, but he had done a carb kit. Well I get it home and put the hose on it, and gas is entering the carb, but it fires up but it wont stay running. The engine jumps RPM and then shuts down, its not pumping water either. I decide to address the water pumping issue and put in a new impellar, so now its pumping water but it still won't stay running, dies in about 30 seconds of starting. I then decide to put new plugs in it and I also replaced the fuel pump. I can now get it to run for about a minute so it seems the fuel pump has helped but the darn thing will cough and then die. So im thinking of taking the carb apart and doing another service on that. When i pump the primer bulb it fills the bowl, but if i keep squeezing, gas will push out the throat and out a nozzle on the side so im thinking something is up with the float. The other thing that im a little worried about is the lower unit. Although its pumping water well, the leg is getting hot, not to hot that I cant keep my hand on it but warmer than any other motor Ive had. I looked at the thermostat and its old but seems to be entact and working. Ill try and get a video of it running tomorrow. Any help would be appreciated
 
If it has been overheated you will see a discoloration of the head and exhaust cover. How is the compression? The leg gets pretty warm on these old girls and as long as you have a clear and open exhaust housing, just keep an eye on water flow. If the impeller was broken up, you could have something plugging a passage in the Powerhead. How did the pump look and why wasn't it pumping? The stalling just about has to be the carb. You had better dig into that. Check spark for good 3/8" blue/white jump. Spark plugs are not the best way to test spark as even weak, problem spark can jump .025 inch.
 
The pump actually looked ok when i took it out, i think it was just worn, the splines a little weak. Ill get a spark tester and look at that, compression is good, but yea im thinking more and more its the carb. When i squeeze the bulb and it gets hard it should stay hard right? I shouldnt be able to force more fuel into the bowl if the float is working correctly?
 
Right, but while its running,the bulb will be softer as it is in a vacuum mode. Weak impeller "fingers" have to be pretty bad to not pump any water on this motor, that is odd to me.......perhaps instead there was not enough water to get the old dry pump properly primed. The intake side of the pump has to be cleaned and checked too, often this is overlooked.
 
Get a rebuild kit for the carb and give it a thorough cleaning. Pull on the rope slow if it has good compression on both cylinders the rope will be hard to pull. Put it in a barrel of water to properly test the water pump. Pull the thermostat and start it up water should quickly gush out the hole. Are the plugs wet with fuel when it stalls? Sounds to me like you have a stuck float sometimes just tapping on the side of the carb with a wrench while running will get the float working again.
 
Right. The screen in the fuel pump may not be making a perfect job of filtration. The fuel system from there back to the tank may need to be flushed and cleaned. Nothing goes out of my shop here in Minnesota that has had carburetor work done by me, that the hose and fuel tank have not been thoroughly cleaned. The guy can have his old gas back and do what he wants with it. You will not BELIEVE what I have found in fuel tanks and hoses.
 
THanks for the help and responses guys!! Im gonna go home and take the carb apart, clean it up, get a rebuild kit, next time i start it up ill take the thermostat out see how it pumps, ill give you guys an update once i do that. Thank you again.
 
Hey so I have an update. I cleaned the carb and put it back together. I am now able to get it running for over a minute however; the leg is getting piping hot and the water coming out of the exhaust is steaming!!!! I know it shouldnt be getting that hot. There seems to be a lot of water coming through the exhaust hole so I know its pumping pretty good? Would this indicate the thermostat is not working?
 
Another update, so i pulled the thermostat cover and pulled the thermostat out. I ran the motor which seems to be starting and running better. Water took about 7 seconds but then started gushing out of the port. I shutdown the motor, replaced the cover for the thermostat housing but I did not put the thermostat back in. I ran the motor for two minutes like this and much better results. Water coming out was warm but not super hot and the leg stayed really warm but not hot like it was. I was also able to run the motor down to a point where i could pop it into forward and reverse before it coughed and died so I think i just have to dial in the needle.
 
It sounds to me like the thermostat is working properly do not run it without one. With the thermostat in run it for five minutes and put your hand on the head. You should be able to hold your hand there for a slow count to six.
 
You said that you "replaced" the fuel pump. Okay, but was it new or used? I usually don't go used pumps unless I completely inspect them and they meet my standards. The diaphragms will stretch out and dry up from sitting and won't deliver an effective pulse. You will run low on fuel and the motor will die. As a simple test, put the tank on a level a couple feet above the motor. A siphon will be created and you will then get adequate fuel delivery.
 
You also mentioned the water pump was worn? If there are grooves on the plate or the housing is pitted it needs to be replaced it will cut down on the life of the impeller.
part # 0382468 for the complete kit
 
new fuel pump, i dont mess around rebuilding them, unless a new one would be ungodly expensive, but they are cheap enough and it looked like the fuel pump was almost original to the motor. It was old, and i was okay with buying a new one. The housing looked ok, and honestly its pushing a good amount of water through the exhaust hole and when i ran it without the thermostat and housing cover, there was a good amount of water being gushed out.
 
If you have any doubts replace the thermostat do not run it without one. It will greatly cut down on service life and performance. Get a jug of salt away and run it in a barrel for at least half an hour with the saltawy in it. feel the exhaust cover on the side of the engine it should always stay somewhat cool. If it is getting hot you need yo pull the covers and head and clean the circuits with a small wire. put on a new head gasket and cover gaskets and then run it again in the saltaway to flush the corrosion, silt and minerals out.
 
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SaltAway got it. yea thats what i was thinking next, ill probably just replace the thermostat since its so old and its only like 12 bucks. Hopefully the saltway works and i dont have to pull the head covers and replaced all that and retorque, but if i do i do.
 
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