89 Evinrude 150 alarms

bakerjw

Petty Officer 1st Class
Joined
Apr 3, 2013
Messages
288
I know that this is kind of an open ended question so please bear with me.

I picked up an 89 Evinrude 150 on an 1850 center console Stratos.

I took it out on the water the other day and it didn't seem to be pumping much water out the visual indicator tube. It increased if I increased RPMs so I got it on plane without too much trouble. After a minute or so, the alarm started intermittently beeping. I took it back home and dropped the lower unit to replace the water pump. Since the boat has an unknown history, I figured that it was cheap insurance.

I also pulled the thermostats and flushed water back through the motor from the top down and the bottom up. Everything seemed to flow well. I replaced the thermostats and the water pump last night. It did take a second try to get the shift rod adjusted but once that was complete, everything buttoned up nicely.

We took the boat out again today. The water pump pressure was much better. It popped off a line in the cowling that fed into the siphon tube. There was also good pressure to the temperature gauge up front.

So, I have good water pressure. The temperature gauge shows in the middle. The motor isn't generating the RPMs that I would expect. 4600 or so with a 14.5" x 19" prop. And I get occasional alarms.

Someone removed the VRO injection from the motor.

What alarms are there on these motors? And what is the best way to track them down?

I still have to do a compression check on all 6 cylinders and check for spark. I'm just trying to get a game plan to track down the warning.
Any help is appreciated.
 

boobie

Supreme Mariner
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Nov 5, 2009
Messages
20,826
Re: 89 Evinrude 150 alarms

With the vro gone you should a have only an over heat alarm. Or is the vro still there and you're using it just for a fuel pump ??
 

bakerjw

Petty Officer 1st Class
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Apr 3, 2013
Messages
288
Re: 89 Evinrude 150 alarms

Thanks a lot for the quick response.

My ignorance will show now.
The oil tank and associated lines and wiring have been removed. But, I don't know about the VRO pump.
It may or may not be there.

I don't think that it is overheating as I did observe good water flow and the thermostats were both replaced. It could be a bad temperature sensor. I'll have to track them down on the schematics and check them out.
 

bakerjw

Petty Officer 1st Class
Joined
Apr 3, 2013
Messages
288
Re: 89 Evinrude 150 alarms

I just checked and the majority of the VRO system is still there. Can that be causing issues with the alarms?
 

boobie

Supreme Mariner
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Nov 5, 2009
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Re: 89 Evinrude 150 alarms

Are the wires coming out of the vro still connected to the mtr harness. If so, disconnect them and tape 'em.
 

emdsapmgr

Supreme Mariner
Joined
Dec 9, 2005
Messages
11,551
Re: 89 Evinrude 150 alarms

A constant horn is for an overheat or high fuel vacuum. Intermittent horns are VRO-related. Follow boobie's suggestion.
 

bakerjw

Petty Officer 1st Class
Joined
Apr 3, 2013
Messages
288
Re: 89 Evinrude 150 alarms

Thanks guys. I greatly appreciate the advice and suggestions based on your expertise.

Using Evinrude schematics and parts diagrams while looking over the engine, I have followed where the incoming fuel line goes to the (I assume) fuel pump. The fuel pump appears to be diaphragm driven by pressure from the engine. The incoming oil line goes to a smaller assembly on the back of the fuel pump. There is a 3 wire bundle (gray, tan and black) coming from this that IS still connected to the wiring harness. I am assuming that this is the connection for the VRO and it hasn't been disconnected.

The one thing that I didn't replace yet is the inline fuel filter in the engine compartment. I previously drained the tank and replaced the screw on fuel filter and water separator. If the old filter was full of gunk, it might be limiting fuel into the fuel pump.

The schematic shows a cut off switch that looks like the fuel vacuum sensor that is mounted high on the engine.

I also know where the port and starboard temperature switches are located.

The next time that I take the boat out, I can easily disconnect each of these sensors and determine which one is causing my alarms. Hopefully it is just the VRO.

Any other recommendations are greatly appreciated.
 

boobie

Supreme Mariner
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Nov 5, 2009
Messages
20,826
Re: 89 Evinrude 150 alarms

Maybe I missed it but are you running a 50:1 oil/fuel mix ??
 
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