Evinrude 225HP overheating not pump/thermostats

[eve225]

I have a 1989 225 evinrude motor, with a recently rebuilt power head, (2 years ago), any way the motor is overheating, setting off high temp sensor on starboard side. I already have (not in this order) replaced waterpump, thermostats, pick up tube, temp sensor, pulled head cover, checked head gaskets, good compression in all cylinders. The motor is definetly overheating not just hot. I have tried everything and I planning on pulling powerhead to check gasket where powerhead meets mid section for leaks. Motor runs mint, never a problem til now. Any other ideas or suggestions would much appreciated. I know that power head may be cracked internally but I am hoping it isn't and i think there is no way to test for this?? Help<br /><br />Thank again

 

[rickdb1boat]

Re: Evinrude 225HP overheating not pump/thermostats

Simple, but did you check the pick-ups on the lower unit for obtructions? It Happens! Did you check the temp of the head with a thermomelt stick to see how hot it's getting? Also, is timing set correctly?

 

[eve225]

Re: Evinrude 225HP overheating not pump/thermostats

Yes motor is definitely overheating checked with new gauge and by replacing overheat sensor on starboard side. Motor is only overheating starboard side. Timing is OK as well. Pick ups are clear checked while replacing water pump, you can see right down to screens.

 

[rodbolt]

Re: Evinrude 225HP overheating not pump/thermostats

hello<br /> try testing the water control valve. if it is trying to hold the thermostat on the seat it will get hot. the tstat alone cant flow enough water at high speed. and remember all the water you put in must get out. dont forget to check the discharge ports.<br /> good luck and keep posting

 

[eve225]

Re: Evinrude 225HP overheating not pump/thermostats

Thanks , but on this motor the thermostat and pressure relief are all one unit, also how could i check the discharge ports where does the water flow out besides the tell tale. PS the motor runs cool or cold when thermostats/pressure reliefs are removed from top of blocks

 

[BillP]

Re: Evinrude 225HP overheating not pump/thermostats

Maybe the tstats are defective or assembled incorrectly. If it runs cold without them I'd say you elimated a lot of other possibilities of the overheating. Can you swap tstats on this engine to see if if overheats the other bank?

 

[eve225]

Re: Evinrude 225HP overheating not pump/thermostats

Tried it but still runs hot at speed

 

[rickdb1boat]

Re: Evinrude 225HP overheating not pump/thermostats

At this point, I'd double check the water pump installation & the water pick up tube<br />.

 

[bollard]

Re: Evinrude 225HP overheating not pump/thermostats

Just a suggestion, but I have seen an engine run lean at high speed and heat up like crazy. May want to check the fuel system for clogged filters or other restrictions. Usually one carb (or part of one) will be the lean inlet and so the hottest part will be on the lean side.

 

[eve225]

Re: Evinrude 225HP overheating not pump/thermostats

Found exhaust gases in water. At top of block. There is exhaust gas in cooling water, We also found a bad gasket where power head meets mid section I will test run tomorrow but there was no exhaust gas after replacing gasket. And was running cooler. Have any of you ever heard of this problem or have an idea why it might have happened

 

[eve225]

Re: Evinrude 225HP overheating not pump/thermostats

We replaced the gasket where the power head meets the mid section. Boat is now running correct temp again. We think that when the power head was replaced it was not tigtened enough or the gasget was pinched. just thought you guys would like to know thanks for the help. by the way has any one heard of this before??

 

[93bronco]

Re: Evinrude 225HP overheating not pump/thermostats

this just happened to me last week.<br />an oversite on my part of not following the manual.<br />-<br />hopefully after your motor reached operating temp - you shut it down to retorque bolts/nuts.<br />thats what i neglected to do & got the same situation.<br />-<br />im pulling my power head in the morning to replace my base gasket.