1993 evinrude 90 hp overheat

[jkgroff]

My motor only overheats when running wide-open. I've replaced waterpump and thermostats. From information I've gotten, I need to replace water flow jackets inside the head. I've never pulled heads before. Any tips or helpful information?<br /><br />Thanks

 

[Dhadley]

Re: 1993 evinrude 90 hp overheat

What youre after are the deflectors. There will be 4 small pieces of rubber hose in the water passages. 2 on each side. They swell with age and "pooch" out into the passage. That actually slows or stops the water flow.<br /><br />Pulling the heads isnt a big deal. Just pull the head bolts, unhook the temp sender wire, remove the t-stat hose and pop her off. <br /><br />While you have the head off you may want to think about pulling the cover plate off and cleaning out the passages in the head. <br /><br />You may have to use heat since this is most likely a salt water motor. Take your time.

 

[DHPMARINE]

Re: 1993 evinrude 90 hp overheat

No big deal pulling the heads.Once they are off try removing the water covers on them and see if the passages are blocked or reduced by corrosion. Also in the block water passages there are rubber water defLectors to check that slow the water down,so it will absorb and draw out heat.<br /><br />Start right,get the factory service manual so you have torque patterns and specs,and it should aslo show you where the defLectors should be located.<br /><br />DHP

 

[Solittle]

Re: 1993 evinrude 90 hp overheat

Make sure that you use new gaskets on reassembly and torque the bolts to spec - see the manual for values.

 

[jkgroff]

Re: 1993 evinrude 90 hp overheat

The motor has been used in saltwater. How do you loosen bolts with heat? Will a little hand held propane torch work?

 

[OBJ]

Re: 1993 evinrude 90 hp overheat

The idea with heat is to apply it to the area around the bolt. This will cause the metal around the bolt to expand a little releasing (hopefully) the frozen bolt. Being patient with frozen bolts helps.......as well as harsh language.....

 

[jkgroff]

Re: 1993 evinrude 90 hp overheat

Bringing this old post back...I need a good mechanics help...I replaced the water flow restrictors and installed a new head gasket. I ran the motor in my driveway with water muffs on. It ran fine for a couple minutes then water sputtered a little bit out the tell tale. Then the overheat alarm went off. The water coming out was verywarm. What should I check...<br />Thank You

 

[reeldutch]

Re: 1993 evinrude 90 hp overheat

whats the condition of your water pump?<br />thermostats?<br />just pumping water doesnt mean you have sufficient water pressure.<br />if your tell tale sputters you might want to check the waterpump. <br /><br />good luck

 

[jkgroff]

Re: 1993 evinrude 90 hp overheat

Hey reeldutch<br />The water pump is new, the thermostats, are new, they werte replaced a few months ago, only a few hours on them. Is there any way to check for blackage elsewhere. Or to flush out cooling system?<br /><br />Thanks

 

[reeldutch]

Re: 1993 evinrude 90 hp overheat

take of the lower unit and blow out the system with compressed air into the water tube.<br />make shure the watertube is ok.<br /><br />also you can disconect the hoses from the heads that go to your tstats put some longer hoses on the heads bring them outside the lower pan<br />and run the motor.<br />there should be plenty of water gushing out.<br />motor should run cool.<br /><br />if this checks out ok the stats might not open.<br />stuck closed.<br /><br />if it still runs hot take of the heads and water covers. you will be surprized how much crap you will find in there.<br />this is a saltwater motor right?<br />you always flush after dipping in the salt pond??<br /><br />what are your compression nrs?<br /><br />your welcome

 

[dc in ms]

Re: 1993 evinrude 90 hp overheat

FYI,<br /><br />My V6 ran hot on starboard side at some point in the past. I was told the pressure valve on the opposite side probably stuck open causing a low or no flow condition on the starboard side (diverting water flow). This does make some sense. Any one seen this before?

 

[reeldutch]

Re: 1993 evinrude 90 hp overheat

is it corrected?