Differant warning alarms.

[DPH]

O.K. I have a confusing story however I will do the best I can.
I own a 1993 115 Johnson. While at idle I got a no oil alarm. Turned the motor off and right back on with no alarm. App. 5-6 min latter no oil alarm. Again turn motor off and right back on and no alarm. Ran the boat wot for 15-20 min and got an overheat alarm. Slowed down and check intake and water comming out of the (p) hole was cool, with good water pressure. Ran boat and alarm went off by itself. The next time I took the boat out I premixed the gas just to be safe. I know the VRO is working since I am going through oil. I know the motor is not overheating since I was in clear water, had good water pressure, and the water coming out of the motor was cool. I have run the boat a few times, and now I just have and intermentant over heat alarm that will go off and on with no change in operation. For example I will be running the boat at 4500rpm and the overheat alarm will sound (with good water pressure) and than turn off by itself 1 min later? I thank I just have a bad horn, or a short somewhere any other advice???

 

[Cofe]

Re: Differant warning alarms.

Get or borrow a temperature gun. A motor can over heat even though it has a good stream of water. (a thermostat controlls water to the heads.) A thermostat may be not working. Check the head temperatures.

 

[ezeke]

Re: Differant warning alarms.

The telltale lets you know that the waterpump is functioning, but tell you nothing about the flow of water through the cooling passages of the engine (or lack therof).

You could have a blockage in the thermostat housing, or bad water passage deflectors.

If you have confirmed that your engine is not actually overheating, check the wiring for a short in the tan wire, especially at points where the harness bends a lot and at the harness plugs.

 

[DPH]

Re: Differant warning alarms.

I will try this. What is the tempature range I should be looking for? Also any reason the oil alarm was going off and now its not, or was it just a coincidence?

 

[Solittle]

Re: Differant warning alarms.

The temp gun should have a range from normal atmospheric temp to well over 200 degrees. Your engine should run around 140-145 degrees with the thermostats open. One head will normally be a tad higher than the other. The temp gun is also useful to determine hot spots.

No matter what the temp gun tells you it may be time to service the water pump and possibly the thermostats. If your engine is a cross flow you may need to replace the rubber water restrictors in the powerhead as well.

I would not recommend running your engine hard if at all after those alarms go off. They go off because something is wrong.

 

[DPH]

Re: Differant warning alarms.

Thank You. Are the thermostats easy to get and replace?

 

[ezeke]

Re: Differant warning alarms.

If your engine is a crossflow, then yes, servicing the thermostats can be time consuming and tedious.

 

[marinemech1]

Re: Differant warning alarms.

you didn't specify what your engine is ...your overheat alarm could be a fuel restriction if your motor is equipped with that senor ie v-6??
Wayne

 

[marinemech1]

Re: Differant warning alarms.

oops didn't see 1993 115...my bad
overheating at speed could be cause by.... a weak water oump,restricted water flow bad thermostat etc.
Probably the pump is drawing exhaust gas into itself due to a worn seal and pump liner....disassemble inspect and install a water pump kit. if you didn't find problem check head temp when horn sounding.use water before touching as you could burn your fingers motor should be warm but not hot on both heads.
Wayne

 

[DPH]

Re: Differant warning alarms.

O.K. which one should I start with. The water pump (whitch was replaced less than 2 yrs. ago.) or the T-Stats?

 

[bob johnson]

Re: Differant warning alarms.

I dont know why more people dont have temperature gauges, and water pressure gauges...

these are the tools needed to monitor the most common dangers to the outboard!!!

bob

 

[ezeke]

Re: Differant warning alarms.

If the water pressure appears strong, then check the thermostats. You will need a kit: http://www.iboats.com/mall/partfind...gd_poid=111072&gd_row=49&**********=694345508

 

[DPH]

Re: Differant warning alarms.

BOB I do have a pressure gauge and it as always showed good pressure throughout the process. I think after all of the great advice and information I have learned I am gonig to go ahead and rebuild water pump (since it has been almost 2yrs.) and replace thermostats. Just have never done t-stats before and was courious how hard it was tho get to them and replace, and if there are any "tricks to the trade" that I need to be aware of before tearing into it. Again thanks for the help.

 

[bob johnson]

Re: Differant warning alarms.

whats good?

if you water pressure is very good..then that is saying your water pump is excellent...

it is doing all it can DELIVERING water under a lot of pressure.

the problem then lies someplace else...

maybe..thermostats...if you had a temp gauge you could watch the temps rise and if they didnt fall back off at about 160 ish. then you know the t-statd didnt open

or you may have blockage...

so if your pressure was showing excellent
and your temps fell all of the sudden at 160 degree back down to 120, but then rose again....up past 180 and to 200 or more, then it pretty much says you have blockage or your motor has LOTS of friction!!!!!!

it isnt operating mechanically correct...

good luck

bob