# Loss of power ?



## Djknyork (Dec 14, 2014)

Hoping I'm missing something guys. My '98 evinrude 40/28 went into limp mode last 2x out (took taking it out a 2nd time to even have a clue what it was, plus first time it happened was about 100 yards from the ramp). 
I took it in & the mechanic pulled weeds from the thermostat n said they were likely the culprit as they were likely not allowing it to fully open to provide full cooling at full throttle). Took it out today & it didn't go into limp mode so the overheat issue was fixed but I fear the damage may have already been done cause both my buddy & I noticed a lack of power & n increase in the amount of time to get on plane. So I thought one of 2 things: 1 somethings wrong with the pump or 2 a scored head. 
Other info: no increased smoke, no unusual sounds, idled fine just didn't rev up as quick as normal. 
I also noticed water coming from what appeared to be indents at the top of the pump (see video). For all I know it's always done this but wanted u guys opinions. Is the water squirting from the top of the pump normal? Could this be the cause of my loss of power? Thank you in advance guys.


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## PA Delaware Fisher (Dec 14, 2014)

I am no mechanic but that has to be the reason you lost some power. Maybe the guy who took it apart didn't torque it back down enough.


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## Djknyork (Dec 14, 2014)

Thanks it doesn't look right for sure but like I said I don't know if it was always doing this or not. 

Oh... The video was taken at idle on the trailer & the water pump was recently professionally changed (oddly enough about a month before going into limp mode).


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## BigTerp (Dec 15, 2014)

Looks like the pump/adapter plate isn't seated/sealed properly to the midsection. I'm sure your losing some pump efficiency with the water coming out like that. From the video it also looks like it's coming out in other areas where the pump/adapter plate meets the midsection. Actually just watched the video again, water should definitely not be coming out like it is. Its spraying from all parts of the top of the pump. Your definitely loosing pump efficiency that way. I would take the pump and adapter plate off and re-install it properly.

And the plugged up thermostat sounds like that for sure caused your overheat issue and going into limp mode. I never used to check my thermostat until JoshKeller pulled it for me and showed me all the trash it collects. Now I check it and clean it out regularly.


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## Lil' Blue Rude (Dec 15, 2014)

That's normal for water to come out there on these motors. That's why there's a hole in the front of the plate and the front of the mid for a drain hole. The tube the water travels up to the powerhead has a hole in the front of it about 1/8" or so to let water spray back down on the water pump to keep it cool since it's in the midsection with the exhaust. The pee tubes not the only place on these motor that water exits. There's also a second hole on the left side of the exhaust in the midsection where water come out into the midsection. So that's why there's water coming out like it is not because the adapters loose. There's no way for the water from the jet pump to get into the mid like that for it to loose any efficiency. Only other thing would be if the gasket that goes between the water pump and the pick up tube was damaged or missing but I think you would still have a over heat problem and a poor pee stream. 
Have you checked compression? Have you checked to see if the impeller was shimmed correctly after the water pump was replaced? Might have warped the head or cracked the head gasket. Probably wouldn't hurt to replace the head gasket. Just make sure to use a torque wrench and torque them to 18-20ft. lbs. Start on one of the middle bolts then go right or left depending where you started then up one then over to the one beside it then back down below the first two doing the same thing until all are torqued.


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## Djknyork (Dec 15, 2014)

Thanks for the replies guys. 
I believe the mechanic took one shim from above the impellar n put it below when he changed the water pump. Sounds like I need to take it to the shop n have the compression checked & maybe a new head gasket installed. I know this has probably been covered elsewhere but if compression is low that means what? Head warped, blown gasket, scored cylinder - any/all of the above? 

Im really hoping this isn't a terminal issue I really liked this motor, I thought it really did well for as small as it is.


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## BigTerp (Dec 16, 2014)

Lil' Blue Rude said:


> That's normal for water to come out there on these motors. That's why there's a hole in the front of the plate and the front of the mid for a drain hole. The tube the water travels up to the powerhead has a hole in the front of it about 1/8" or so to let water spray back down on the water pump to keep it cool since it's in the midsection with the exhaust. The pee tubes not the only place on these motor that water exits. There's also a second hole on the left side of the exhaust in the midsection where water come out into the midsection. So that's why there's water coming out like it is not because the adapters loose.



This is interesting. Rude knows MUCH more about these motors than myself. But I'm 99% sure my motor ('94 Johnson 50/35) doesn't throw water out like the OP's. I'll have to double check this Saturday when we are out duck hunting though.


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## Lil' Blue Rude (Dec 16, 2014)

Djknyork said:


> Thanks for the replies guys.
> I believe the mechanic took one shim from above the impellar n put it below when he changed the water pump. Sounds like I need to take it to the shop n have the compression checked & maybe a new head gasket installed. I know this has probably been covered elsewhere but if compression is low that means what? Head warped, blown gasket, scored cylinder - any/all of the above?
> 
> Im really hoping this isn't a terminal issue I really liked this motor, I thought it really did well for as small as it is.



Could be all of the above. Don't figure it would be hurt to bad if you stopped running it when it went into limp mode. More then likely would be a head gasket or something like that. If not rebuild the powerhead or buy another powerehad or short block on ebay, these are good strong motors. The mechanic should have but a shim from the nut side to the pump side of the impeller to shim it closer.
Like I said they all do it some more then others. Just look up some videos on youtube of prop motors idling on the muffs.


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## Djknyork (Dec 16, 2014)

Yes you are correct he shimmed it one shim closer. 
I had to run it probably 15 minutes in limp mode back to the ramp at idle. 
Rebuilding is way past my skill level anybody know about what that would cost?


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## Lil' Blue Rude (Dec 16, 2014)

I'd guess it's time for a rebuild then. Could be wrong. The limp mode might have keep it from getting too much damage but 15 minutes is a long time for a over heating motor. Like I said before might just be a head gasket leaking or might be scored cylinders causing low compression just have to check and see.


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## JoshKeller (Dec 16, 2014)

best thing to do would be to go to an auto parts store and get a $30 compression tester


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## Djknyork (Dec 17, 2014)

Thanks for the input guys.


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