Any ideas?

NgtvNrg

Seaman Apprentice
Joined
Apr 30, 2007
Messages
49
I've had a reoccurring overheating issue at high speeds on a 1996 Evinrude e90tleda. So far I have replaced the thermostats and poppit valves, impeller and housing, and the water deflectors. I am getting good water flow out of the tell-tale since replacing the waterpump. I ran it on muffs for a few minutes after replacing the deflectors to test for leaks and there were none. What concerns me is that the tell-tale stream gets pretty warm now. It has always been cool before. Is this normal or is there something else I should look into? Any ideas or suggestions would be appreciated.
 

iwombat

Captain
Joined
Jul 12, 2006
Messages
3,767
Re: Any ideas?

My 85hp is usually pretty warm out the stream. Have you cleaned the water intake vents yet? Could have a bunch of crud in there restricting the flow.
 

NgtvNrg

Seaman Apprentice
Joined
Apr 30, 2007
Messages
49
Re: Any ideas?

Thanks for your help. Are you talking about the screen over the water pickup on the lower unit? If so, I checked and cleaned them when I replaced the waterpump. I have seen other post that say the water from the tell-tale doesn't circulate through the engine before it comes out. Is that true? If so than how does it get hot? I am just trying to make sure everything is ok before I test it on the water.
 

iwombat

Captain
Joined
Jul 12, 2006
Messages
3,767
Re: Any ideas?

Yes I was talking about the screen in the lower unit.

As for the water temp. It all kind of depends on where your tell-tale is tapped into the motor. Unless it's right next to the water intake, I'd expect it to get at least some heat transfer.
 

Chinewalker

Fleet Admiral
Joined
Aug 19, 2001
Messages
8,902
Re: Any ideas?

I had a very similar issue with my 1984 90hp where it would pump fine at idle and slow speeds, but at higher speeds it would steam up. Turned out there is a VERY tiny passage in the waterpump housing that must be open. It acts as a vent for the pump. If it is plugged up the pump will lose prime shortly after the pump is no longer submerged, .ie when on plane... I had dutifully installed the o-ring that resides between the stainless steel cup and the housing, including a big bead of sealant in the groove, filling up the passage in the process... Worth a look...
- Scott
 

ezeke

Supreme Mariner
Joined
Sep 19, 2003
Messages
12,532
Re: Any ideas?

Your indicator elbow should be tapped into the lower right hand corner of the exhaust cover and your thermostats are 143 degrees. With that combination, expect warm water.​

Many of the older crossflow V4 motors were fitted with 105 degree thermostats, including the ones from the seventies.​
 

mikesea

Lieutenant Commander
Joined
Oct 1, 2006
Messages
1,830
Re: Any ideas?

that oring that was mentioned is important,believe it is called a quad ring,may have fallen out during service,also,cavitation can cause air to be sucked up,I had an inboard outboard do it ,the causewas a bad prop.hard to believe,but my boat performed perfect until wide open,as a goof,i tried a friens prop just to see if the boat would perform better,not expecting the wot overheat to go away and it did,also,is the bottom clean of barnicles,that could cause turbulant water pick up
 

NgtvNrg

Seaman Apprentice
Joined
Apr 30, 2007
Messages
49
Re: Any ideas?

Thanks ezeke. I went outside an looked and it comes right out of the exhaust cover. I've never noticed it being warm before. Could that have been because it wasn't cooling efficiently? I believe the cause of the overheating to be the deflectors, they were really swollen and rotted.
 

ezeke

Supreme Mariner
Joined
Sep 19, 2003
Messages
12,532
Re: Any ideas?

I would think that it was the result of the new and properly functioning thermostats. If you have other issues, like alarms, pay particular attention to Chinewalker's comments.​
 

NgtvNrg

Seaman Apprentice
Joined
Apr 30, 2007
Messages
49
Re: Any ideas?

I removed the lower unit, took the waterpump apart and reassembled it. Put the muffs back on and ran it for about 5 minutes. This time the tell-tale stream didn't even get warm and I could leave my finger on the heads for about 10 seconds. While I had the lower unit off I put a water hose on the water pickup tube. Some water came out from around the section that houses the tube. Is this normal or something I should be concerned about?
 
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