evinrude overheat problem

[tylerr83]

I'm sure you guys have seen my previous posts about an 87 evinrude 50 that i've had an overheating issue with. I have replace the water pump and thermostat...and today removed the head to check for a possible blockage in the powerhead preventing good circulation....looked ok...new head gastket on...narrows things down some...i'm giong to finish up tomorrow by replacing the temp switch...if this doesn't solve the problem i'm not sure what to do...it would seem that the only other issue could be with the water line that runs through the midsection....i noticed when i first replaced the water pump that there is no grommet or gasket or anything where the upper part of the water pump connects with the water tube...is this how it is supposed to be...i looked on a parts diagram and there is a grommet pictured....but i think its for the upper part of the water tube where it feeds the powerhead....only other thing i can think of is maybe some blockage in that wate tube?....any ideas?
thanks ,
Tyler

 

[HighTrim]

Re: evinrude overheat problem

There should DEFINATELY be a grommet atop the impeller housing part #0315748. There is also a water tube grommet #0315837. Combined they are about 3 bucks. These could likely be your issue as you are losing water pressure. While the lu is down, I would remove the t stat and flush the water line with the garden hose or compressed air from the water line up to the t stat housing, then back down from the t stat housing to the water line, ensuring there is no blockage. Clean out the water intake area as well. You will also need another t stat gasket. Also ensure that you do not jam the grommet into the impeller housing during re install, it will restrict water flow, causing the same overheat.

http://shop2.evinrude.com/ext/index.aspx?s1=61db945167cb5825f529765e4238e2ca

 

[tylerr83]

Re: evinrude overheat problem

hightrim...there is a grommet atop the impeller housing itself...then there is a metal piece that sits atop that that fits over the water tube...after looking over that diagram with a tech today...seems the grommet that I was referring to is the one at the top of the water tube where it feeds the powerhead....i actually ran the motor this afternoon in the river since removing the head and cleaning any salt and stuff athat was accumulated in there....there was no blockage, but its cleaner now....also replaced the temp switch...did not get the overheat horn...i kept a close watch on how hot the head felt leaving it idling for a long time....it got warm but when i opened up the throttle some it got much cooler...i'm guessing it reached something like 140 and the thermostat opened....so i think this problem is taken care of (i hope) i'm gonna take it for a more extnesive ride this weekend....but in the meantime i have another issue to take care of....after shutting down the motor for a minute at the dock, i went to start it back up and nothing happened at all...i'm guessing its the solenoid. gonna have to troubleshoot that one after work tomorrow....
...all this work just to catch a few fish.....

 

[HighTrim]

Re: evinrude overheat problem

Glad to hear you are no longer overheating, the temp switch was likely your problem.

Before you go replacing the solenoid or starter, start with the basics. Most of these cases are wiring/connection related. Go over all connections with a file or sand paper, then re tighten. Dont just look at them, make them shine, they can be deceiving. Check the wiring for nicks, cuts, abrasions, or crunching when you flex it. These are all sure signs that they need to be replaced. This goes for all wiring/connections at the battery, starter, solenoid,ignition switch, etc.... Do not neglect any grounds.

Disconnect and inspect the large red harness plug in the cowl. Clean it as best you can with electrical contact cleaner, smear some grease around the contact edges and reconnect. Now use the ignition switch to try and start the engine. If it works every time the connector was the culprit.

Measure the voltage at the starter (+) terminal while somebody turns the key over to "start" - if you get within half a volt or so of the battery voltage, the starter is faulty.

Bad voltage at starter (with clean tight connections), measure the voltage at the solenoid small terminal with the yellow/red wire with the key turned over to "start" you should read within a half-volt of battery voltage, otherwise you have a wiring fault between the keyswitch & solenoid. Good voltage at solenoid but bad voltage at starter means faulty solenoid.

Voltage "Drop Testing" is another quick and easy test to determine faulty sections of wiring or components

 

[tylerr83]

Re: evinrude overheat problem

thanks for the tips chris...hopefully i'll be able to get to the bottom of this tomorrow

 

[tylerr83]

Re: evinrude overheat problem

corrosion on the terminal of the power wire to the solenoid....all good now...thanks for the help

 

[HighTrim]

Re: evinrude overheat problem

Not a problem, just glad we saved ya from buying a new solenoid.

Now go catch some fish!