2000 Johnson 90 hp tell tale water very hot

[FlaMtnBkr]

Due to health reasons I haven't been able to start my boat in about a year. I wasn't able to get it running so started messing with it. The gas from tank appeared to have a lot of oil in it. I disconnected fuel line and pumped bulb until clear gas was coming out and hooked back up. I drained gas from each carb float bowl and it appeared it was half gas and half oil. I primed the bulb and got it to start fairly easy. It smoked like crazy so I let it run and then shut it off after a minute and repeated the cycle until it was no longer belching smoke out, which I assume was from all the oil. I have no idea why there was so much oil but I'm not worrying about that for now.

After it stopped smoking I let it run for a few minutes and then noticed the water coming out of tell tale was making steam on the ground. I felt the water and it was quite hot. I shut it down and assumed that burning all the extra oil got things hotter than normal. I let it cool for 45 min and started it again and within 30 seconds it was pretty darn hot. At first I thought the thermostat might be stuck but that doesn't make sense for it to be that hot. There wasn't a great stream of water coming from tell tale, but I would think adequate.

Any ideas what could be causing the excessively hot water (my main concern)? Any idea why the carbs would have so much oil after sitting? Sorry for the long post, but wanted to give some background info. Let me know if more info is needed. It is a 2000 90 HP Johnson and the model is J90plsse (i think, its a bit faded). It is a V4 and has oil injection with the reservoir in the center console.

Any help or ideas will be greatly appreciated! Thanks!

 

[Solittle]

Re: 2000 Johnson 90 hp tell tale water very hot

"quite hot" is not the best measure of temperature. Did your overheat horn go off? Do you have a temp or water pressure guage? Do you know anyone who has an infa red temperature gun? - Should be around 140-145 degrees for most v-4s. Should feel real hot to the touch on the heads but not burn your fingers.

Possibilities are unservicable water pump, stuck thermostats, bad deflectors. other water passage block.

Solve the "overheating issue" for now - run the crap out of it - then think about the smoking.

 

[metriccrescentwrench]

Re: 2000 Johnson 90 hp tell tale water very hot

I can't quote specs for your engine, but I'd bet they're close to the one's I've worked on as far as temps. At idle the heads should be around 145 as mentioned (you should be able to hold the palm of your hand on the head for a few seconds before it feels too hot to touch). At higher speed the head temp drops down to around 125.

 

[FlaMtnBkr]

Re: 2000 Johnson 90 hp tell tale water very hot

So water temp doesn't mean much? I just don't remember it ever being more than 'warm'. It was steaming so that is getting close to 200 deg F. I have a temp gun but it's at other house. I will pay attention to the head close to the spark plug and see how hot it gets. I assume the 145 deg is at idle after a good warm up and it should never exceed that temp.

The boat doesn't have a water temp or pressure gauge and I'm not sure it even has a dummy alarm/light for over heating. I will post back on what the engine temp appears to be. Any more ideas are welcome. Thanks!

 

[FlaMtnBkr]

Re: 2000 Johnson 90 hp tell tale water very hot

I just went and started it up and in around 2 min it was pretty hot. I could only hold my hand to it for a second at most. Also, I am only using bunny ears to provide water. And the boat does appear to have a dummy light for over heating, but I would rather not test it out.

What could be causing it to over heat (?) at idle?

 

[Chris1956]

Re: 2000 Johnson 90 hp tell tale water very hot

Overheat at all speeds can be caused by a bad waterpump and/or bad thermostat. When was the last time the waterpump was rebuilt? If more than 3 years ago, it is probably time....

 

[crb478]

Re: 2000 Johnson 90 hp tell tale water very hot

Can you put it in the water and rev it up over 1500 rpm so the bypass valves in the thermastat open, and everything cools normally? You may not be getting enough water on muffs. Leave the boat on the trailer if you can so you dont end up stuck in the water.

 

[FlaMtnBkr]

Re: 2000 Johnson 90 hp tell tale water very hot

So there is a cooling water bypass valve? You said in the thermostat but every thermostat I have seen opens on temp only (I think?). I was looking for the thermostat but I guess I didn't find it. What I thought might be the housing is on the top of each cylinder bank and has a big nut. But I doubt there are 2 thermostats. It would be nice to track down a service manual so I can look at water flow diagrams as well as placement of thermostat and water pump. I'm sure I can figure it out but I don't want to tear into things that arent what I think they are. I know manual downloads are frowned upon but if someone has one it would be appreciated. I'm disabled and it will be a while before I can buy a manual or worst case, take it to the shop.

I guess at this point I'm not even convinced there is a cooling problem. However, I don't want to run it and risk damaging anything.

 

[FlaMtnBkr]

Re: 2000 Johnson 90 hp tell tale water very hot

Edit: double tap

 

[Chris1956]

Re: 2000 Johnson 90 hp tell tale water very hot

A service manual is a good idea, as the waterpump replacement is not straightforward. I don't think there is a thermostat bypass on that motor.

 

[b4odmnpl]

Re: 2000 Johnson 90 hp tell tale water very hot

Thrmostats are simple to change on this engine. I have a j90plsse. Take your spark plug socket and remove the plastic nut on the back of the motor. They are located high on the block by the spark plugs. Careful. A spring holds the t stat in place. You might need a small screw driver to work the tstat out. I took mine out and found small pieces of sand blocking flow through the tstat. Simple as changing sparkplugs. Good luck.

 

[FlaMtnBkr]

Re: 2000 Johnson 90 hp tell tale water very hot

So there are 2 thermostats on the engine? I guess what I thought was the thermostat was correct. Was there a gasket that needs to be replaced? On other engines there has been a gasket that usually gets torn up when getting to the thermostat.

Edit: Solittle mentioned "bad deflectors". Could someone elaborate?

 

[metriccrescentwrench]

Re: 2000 Johnson 90 hp tell tale water very hot

So there is a cooling water bypass valve? You said in the thermostat but every thermostat I have seen opens on temp only (I think?).

Take a look at your engine diagram at shop2.evinrude.com (go to the 'cylinder & crankcase' diagram for your engine). You'll see that there's a spring behind the thermostats. At low rpm the water pump produces relatively low water pressure and the thermostats stay seated. At higher rpm the water pump produces more pressure and the thermostats lift off their seat, allowing higher water flow.

And yes, before you try replacing the water pump get a FACTORY service manual. I also agree with the idea of checking it with the boat in the water, on a trailer.

 

[b4odmnpl]

Re: 2000 Johnson 90 hp tell tale water very hot

Two thermostats. I didnt see any gaskets. I did put a small amount of pipe compound pn the threads. Probably not needed. I hope you get yours fixed.

 

[JustGreg1957]

Re: 2000 Johnson 90 hp tell tale water very hot

So there are 2 thermostats on the engine? I guess what I thought was the thermostat was correct. Was there a gasket that needs to be replaced? On other engines there has been a gasket that usually gets torn up when getting to the thermostat.

Edit: Solittle mentioned "bad deflectors". Could someone elaborate?

I just replaced my thermostats on a 2002 90HP Johnson and there are o-rings on the plastic covers. No gaskets.

 

[b4odmnpl]

Re: 2000 Johnson 90 hp tell tale water very hot

I didnt see any orings. Maybe some pipe thread compound.

 

[b4odmnpl]

Re: 2000 Johnson 90 hp tell tale water very hot

I am still having problems with engine miss. No real pattern to it. I think its fuel starved and want to clean the carbs does anyone know how to pull the carbs?

 

[JustGreg1957]

Re: 2000 Johnson 90 hp tell tale water very hot

I didnt see any orings. Maybe some pipe thread compound.

If this worked there is a pic of the o-ring #23 on the pic.