1993 Evinrude 88 SPL getting hot

Hello everyone I am new to the forum. I found this during a search to my problems. I do alot of my own mechanic work and have owned a few different Johnson and Evinrude engines. I have a 1993 Evinrude 88 SPL that is overheating. I can put my boat in the water, idle out away from the marina and run at WOT (5000 rpm) for about 3 minutes and my horn goes off. The starboard head is running at 160 degrees and the port head is 200 degrees. (I have tela-temp`s installed on each head) I have installed a new water pump, cup and plate assembly, exhaust cover gaskets,thermostats, relief valves and springs, head gaskets(twice), 4 water restricters, head cover gaskets, powerhead to exhaust adapter gasket, and water passage cover gasket. I found sand in the head covers and in the small passages in the exhaust manifold and cleaned everything. I did notice when I had the powerhead off that there was carbon deposits in the port side exhaust passages that were not in the starboard side. I feel something is wrong on the port side but what could it be??????????? Can anyone help?

Re: 1993 Evinrude 88 SPL getting hot

Stat's working properly ???
Did you backflush the entire system. Sounds like maybe a blockage on one side (the hot one)
Welcome to iboats

Re: 1993 Evinrude 88 SPL getting hot

I have flushed it with a garden hose here at home and I have to believe the stats are working. I just purchased this motor and the first time I ran it it overheated. I started checking and discovered there were no thermstats or relief valves in it. I have to assume the prior owner had the same problem and just sold it. The water restricters on the port side were swelled and had created a blockage which is why I replaced them.

Re: 1993 Evinrude 88 SPL getting hot

Port head just has to have a blockage somewhere. Starboard head is a little warm as well.
How are you checking it ???? on muffs or actually in the water ???

Re: 1993 Evinrude 88 SPL getting hot

I flushed it with a hose but am running wide open throttle at the lake is where my problem is.

Re: 1993 Evinrude 88 SPL getting hot

I think you still have a blockage or partial restriction somewhere in there. What condition was the old impeller in ????

Re: 1993 Evinrude 88 SPL getting hot

When running hard across the lake, the pressure relief valves should open fully. When that happens, there is extra cooling water flow to the powerhead and the temps should decrease-certainly well below 160. I would think they should be under 145 at full throttle, so you are still warm on the starboard head also. You've pretty much taken everything apart and should have found something. You did say you had sand in the head and exhaust covers. When you replaced the 4 water diverters, did you find any sand around the cylinders? I'm assuming you put the new diverters in the correct locations? I've seen them misplaced which will cause overheats. The attached pic shows a misplaced/deformed diverter on the far right of the picture. Carbon accumulation is common on an engine which has been running cool. The prior owner was running w/o stats, so the engine probably never got up to normal operating temps-hence carbon accumulation. You may have more carbon on the ringsets on that side than the other. A decarb with Bombardier Engine Tuner should take care of any concerns in this area. When you put the new impeller in, did you find any restrictions between the water pickup holes in the lower unit and the impeller housing base?
As a last resort, you could pull the flywheel, and then remove the powerhead water passage cover at the top of the block and look down inside for any debris accumlation.

Re: 1993 Evinrude 88 SPL getting hot

The old impeller was not too bad. To answer the other question I have removed the flywheel and looked inside the water passage and found no debris. I have discovered another issue. When I installed this motor the tach was set at 4 and my service manual said it should be set at 6. So with that info I am thinking maybe I am running beyond WOT. If my tach is displaying 5000 rpm but I am actually running 6000 ( or whatever it may be) could this cause it to overheat?

Re: 1993 Evinrude 88 SPL getting hot

I installed the water restricters as shown and I did not find any sand around the cyclinders. I found no restrictions around the impeller housing either. Thanks for all your help.

Re: 1993 Evinrude 88 SPL getting hot

You need to run the tach on the 6 setting to get an accurate reading from the tach. Unlikely that the tach issue is related to your overheat issue. Have you run the engine since you put the thermostats and pressure relief valves back in-does it still overheat? Did you temporarily try hooking a (0-30 psi) water pressure gauge up in place of the telltale-what pressures does it show at idle and full throttle?

Re: 1993 Evinrude 88 SPL getting hot

Yes it still overheats with the new stats and relief valves. I have not checked water pressure, better try that next. Thanks for your advice.

Re: 1993 Evinrude 88 SPL getting hot

Is the water tube in good condition ?? Did all the O rings go where they needed to ??

Re: 1993 Evinrude 88 SPL getting hot

I had a Johnson 88spl around that year model and had minor cooling issues. All of which were fixed with similar work that you said you did. There was one time, however, the deflectors and thermostats were new and it still would get hot. I took the stats out and boiled them in a pan of water. One of the stats would open and the other would not. These were brand new thermostats. I threw both of them away and ran that motor for another 3 years with no stats. It never sounded the buzzer again and I sold it that way. I never had rough idling or weird issues like other claim from not running thermostats. Here in Texas the waters are warm enough to not need them anyhow. Be sure both your stats are opening.

Re: 1993 Evinrude 88 SPL getting hot

When you have the engine idling on the garden hose, you can always pull one (head) hose off at the thermostat housing and check for water flow. Reconnect it, and pull the other one off. If you've got great flow from both hoses, the problem is at the thermostat housing (a restriction) or after it. Running two thermostats keeps the block full of water, as they act like a restrictor.

Re: 1993 Evinrude 88 SPL getting hot

kenmyfam said:

Is the water tube in good condition ?? Did all the O rings go where they needed to ??

Click to expand...

I pulled the lower unit and discovered that when I reassembled it after putting a new water pump in it I did not have the water tube properly aligned and the rubber grommet inside the pump housing came out and turned sideways in the water tube. The water tube is bent and will have to be replaced also. I am shocked it actually pumped water up to the powerhead. Thanks for all the help it is much appreciated.

Trubba

Re: 1993 Evinrude 88 SPL getting hot

Glad you found the problem. Can the tube be straightened out ??? you can use a pipe spring in some circumstances. Then make sure the o rings go back in place.