1974 40HP Evinrude Water flow Problems

[duckmon243]

i'm not getting any water flow out of the ports at the top of the lower unit. i've had the motor for 5-6 years and had a spray there before. just noticed lack of flow last fall while running motor in cold water. the only symptom i noticed was: after idling for some time the motor died then seemed like starter dragged when re-starting. (possibly the pistons starting to seize from being hot?) i've replaced the impeller, didn't help. then replaced the whole pump assembly (impeller, housing, liner etc)still no help. i've also blown air into the water tube that goes into the engine and sounds like air is returning through the exhaust. i would think that that is normal. i've backed my trailer down the ramp and tested in water after replacing parts and ran for 5 minutes or so and appears to run ok just no water flow. i can put my hand on the head and hold for few seconds and doesn't seem real hot. i don't have the manual for this motor but was told when i bought it than there was no thermostat. i live in Nebraska and it's been too cold to work on at the lake but i'm getting ready to give it another try soon. anybody have any ideas?

 

[lmoreau]

Re: 1974 40HP Evinrude Water flow Problems

I can't even see mine as my Ouachita steers from the bow...I was told by local dealers that there should just be a dribble or mist if anything at all. Almost all of the water is expelled through the prop and foot. If it wasn't hot after 5 min, take it on a cruise RPM ride for 10-15. If no buzzer and the heads are scorching, you should be ok. May want to test your buzzer first!

 

[DJ]

Re: 1974 40HP Evinrude Water flow Problems

duckmon243,<br /><br />At idle, the most you would ever get out of those ports is a spray. At planing speeds you would get a slow stream. Those are exhaust relief ports.<br /><br />Yes, your engine has a thermostat. It is necessary to have to make the engine run properly. It is under the water jacket cover on the head.

 

[duckmon243]

Re: 1974 40HP Evinrude Water flow Problems

thanks for the feedback! one thing that you both mention is a slight spray. this is on a 16 ft flatbottom and has tiller steering. before, when i was running on the water i could look around the motor and see a fairly good water spray coming from the exhaust relief ports.<br />any ideas what might have caused a change?<br /><br />one other factor that i might mention: this problem came up during the very last part of duck season. weather was nasty, the water was very cold. the blind that i use during the season doesn't allow me to look out and around the motor to see if there is any water flow when running high RPMs when underway. when idling i could look back and check and noticed no spray. after replacing the water pump, i only ran the motor on the trailer cause the lakes were starting to freeze up and i didn't want to get stuck out far away from a boat ramp. weather just wasn't right for a shake down cruise.<br /><br />DJ: i have 1977 35hp johnson and i can see a bulge on the head where the thermostat is. i can't see anything that looks like that on this 40hp 'rude. i have gotten conflicting reports as to if this motor has a thermostat or not. do you have the manual or are you confident that i do or don't have a thermostat? if i do have a thermostat could this be part of the problem? would the water being cold last fall be a factor?<br /><br />Lee: by the way: this is on a 16 Ouachita. Great old boat! I must note that this motor does not have thru the prop exhaust. it also does not have a buzzer. i wish it did. how can i tell if it's overheating or getting too hot? i don't want to damage the motor due to overheating.<br /><br />thanks,<br />duckmon

 

[DJ]

Re: 1974 40HP Evinrude Water flow Problems

duckmon243,<br /><br />I do not have a manual but I am reasonably certain your engine has a thermostat.<br /><br />The cold water will definetly have an effect on the amount of discharge.

 

[duckmon243]

Re: 1974 40HP Evinrude Water flow Problems

thanks admiral! i'll have it in the water soon. i'll let you know what happens.

 

[kwoolard]

Re: 1974 40HP Evinrude Water flow Problems

I have the exact same motor, just a Johnson instead. It does not have a thermostat!