1997 90hp running hot warning

[roach]

Ran all day mostly idling in no wake area. Before i went home decided to run WOT clean the
carbon and oil out of the exhaust. After about a minute high temp alarm goes off. At this point
I throttled back to motor idle and checked for water flow at the telltale and water was coming
out. Water was not hot or warm. Water temp was lake water temp probably around 45 degrees.
So the alarm went silent and I drove back to launch ramp at about 3300 rpms. No problem
with high temp alarm now. Wondering where I should start looking at first... Water pump
replaced in 2013..... what about thermostat replacement...… what's the best way to
troubleshoot these issues?

Thanks in advance,
Kevin

 

[Chris1956]

Well, 6 years is long for a waterpump. If sand gets into it it can really shorten it's life.

Thermostats do not last forever either. Inspect them. Replace them or test them.

 

[racerone]

There are 2 totally different 90 HP motors in 1997.----So post your model #

 

[roach]

Model 90TSLEUA

 

[Fed]

If you can drive around at 3300 and below then your water pump & thermostats are OK.

First suspect would be water deflectors.

 

[racerone]

Telltale will fool you.------Fact---The water that comes out the tell tale does NOT go through the engine block.------It can pee like a small pony while there is internal blockage inside the block.

 

[flyingscott]

Is the VRO hooked up? and which alarm are you getting exactly?

 

[oldboat1]

Tops of the heads too hot to touch? Get an infrared tester and check temp.

 

[oldboat1]

^^... Which is to say, a main threat is overheating with any outboard. Need to check the temp if any hint of overheating -- you mistakenly or prematurely rule out overheating at your motor's peril.

As was also mentioned, you are due for at least impeller replacement, and can't count on tell-tale as a temp indicator, or temp of intake water, etc. And if that's not enough, can ruin your motor if it's not getting lubrication, as hinted at in #7.

Can't guess at this stuff.

 

[Fed]

Thinking out loud here, that motor could have a vacuum switch on it.

How long after backing off did the alarm take to go silent?

If it went silent very quickly say bless than 15 seconds then you could have a fuel restriction but if it took more than a minute then it was probably a high temp alarm.
Both alarms are a continuous beeeeeeeeeeeeeeeeeeeeeeeeeeeeeeep.

 

[racerone]

I doubt that this V-4 model has the ---FUEL RESTRICTION ----switch on it.----I doubt that it has VRO on it.

 

[oldboat1]

good point. No oil warning signal. Must premix at 50:1, and trust your memory. Recommend a set routine for refueling to insure that 2-cycle is added in the right ratio. Might also mention that the motor has a water-cooled regulator or regulator/rectifier, and that little jewel can light up if there is insufficient water in the block. I would think muffs are a little risky in that regard, but don't think I've seen that spelled out anywhere.

 

[roach]

I have an infared temp tester. What would be a good/ bad temp reading? Point
it directly at the head next to the sparkplug? Also no VRO, Also I carefully do my
premix at 50-1. No water cooled regulator/rectifier.

 

[oldboat1]

Top of the heads (not area of the plugs). Temps should typically be in the 130-140F range when the engine is warmed up. 160F is too hot.