I have an '89 Evinrude xp150 that the hot horn will go off about 1 - 1 1/2 minute idle time after starting up. Local boat mechanic just put in new water pump and thermostats, and it did it to me again. Does anybody have any ideas what the problem could be?
Is it a solid on all the time, once every other second, or once every 20 seconds?
Yes, it's solid all the time. Also did not know that I needed to mention model number and serial number.
Model number : TJ1505LCEM
Serial number : R 08194674
That's why there is a rule #1. Do you have a water pressure gauge? How is the flow from the overboard disharge? What is the condition of the intake screens in the lower unit? Was it overtemping before the water pump replacement?
also make sure your last water pump was not missing any rubber if so it could be in your motor still make sure your temp is not acting up and see if any water is comming out from your midsection where your power head is bolted on bad gasket will cause lost of water
water pres. gauge has been pegged and does not work right, water discharge seems normal, screens look good to me (not broken or plugged, if I should be looking for something different let me know) yes the alarm went off before we changed the water pump. The old pump was only 14 months old and 6 of those months was in garage winterized. We have had the boat out 3 times before this started with no problems. When we went to go the next time horn went off just after backing off the trailer. Old water pump still looked good but was changed just as a precaution. Thermostats seemed to be slow to open so he changed them.
I don't think the motor would overheat just running 1to11/2 minutes if the water pump was working at all. OK. so where are we? Now we must determine what warning horn system is causing the horn to sound off. These systems will have brown wires to them. To find the problem you must disconnect each system one at a time until the horn stops. The horn is turned on when it is grounded, make sure that anything you unplug is not touching the motor if you leave it unplugged. With the motor running and the horn sounding off I would first unplug the knife connectors one at a time at the temp sensors in the heads. You can leave these unplugged. Then I would unplug the brown wire to the VRO oil tank you can leave this unplugged, then I would take the brown wire off of the grey switch with the little line running from the fuel line, you can leave this off. Next unplug the VRO pump, follow the wires from the VRO to the black plug, take off the wire harness around the plug and pull it apart. Plug the VRO back together. If the horn is still sounding it must be that the brown wire is shorted to ground somewhere, wireing harness to control box or more common a pinched wire in the control box. If you have the horn that chirps when you turn on the key they usually fail with the key on and the motor does not have to be running. Of course if you find the problem connect everyting back up. I hope this helps, Oldtimers like to talk a lot.
Your tech should have an IR temp gauge he can check the head temps with. If not he can use thermosticks to check them. Could be a defective sender too. Your tech could also test water pressure by popping in his pressure gauge in to the T for your gauge. Do the tests like Jerry says.
Thanks for all the help guys. It's going back to shop on Thurs. and I'll let you know how it turns out. Hopfully fishing on Sat.
I believe this crossflow motor has a fuel restriction sending unit with brown lead and small hose connected to it from main fuel linein motor cowling. It is located on either side attached to the intake covers high on the block. This will cause a constant horn signal. either it is defective or you do have a fuel restriction in suction side . service manual has the particulars on how to check it. hope this helps you.
It was a fuel restriction problem. He changed primer bulb and all is well. Thanks for all the advice.
Glad to be able to help, Thanks, david.
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