1998 90hp SPL running warm, voltage too

[skiffinNH]

Anybody familiar with the Evinrude 90spl? Short story, had a remanufactured power head swapped in nearly 3 years ago. Engine runs great, compression is great, plugs are new, along with plug wires, and this year, a new electric choke. Two weekends ago I noticed the temp gauge start to creep up to the upper half of the spectrum, well above where it normally hung out. I immediately checked the pee stream and it was fine. So I continued watching the temp, and it climbs as I throttle up, and slowly subsides as I throttle down and eventually idle. At the same time, I've noticed both on my dashboard gauge and on my fishfinder digital readout, that I'm pushing nearly 17 volts through my system. So my question is, can a bad voltage regulator, and thereby too much voltage in the system, cause the temp gauge to act funny? I replaced the impeller yesterday (monday) morning and the symptoms stayed exactly the same...the boat otherwise runs well save for the occasional "sneeze" when i come down off of a higher speed run..Thanks anyone who can give me a bit of guidance

 

[Chris1956]

Re: 1998 90hp SPL running warm, voltage too

Yes, The temp gauge is electric, and high voltage will cause it to read inaccurately. Ditto for Gas gauge.

Does that motor have a rectifer or a VR on it?

 

[ondarvr]

Re: 1998 90hp SPL running warm, voltage too

A 90 spl only has a rectifier, no regulator, so the voltage will climb as RPM's increase.

I haven't had the gauges change readings with the higher voltage, but I guess its possible.

Turn on some lights or create a draw on the system to lower the voltage and see if the temp gauge reading changes.

 

[skiffinNH]

Re: 1998 90hp SPL running warm, voltage too

Thanks for the replies guys. Here's a little more info. At idle, I am showing about 13-14 volts, both on the digital read-out on my Garmin, as well as the gauge on the dash. At idle the temp sits in a low range, but as I accelerate, I watch the volts soar up over 17 or so while the temp climbs over the 150ish mark. I'm just concerned about a blockage or something within the cooling system. The boat is used 99% in freshwater, always flushed out w/ muffs after the rare salt water use. The powerhead is only 3 yrs old, and the entire cooling system got a "once over" during the re-power... The pee stream is strong, so I know water is at least circulating through the block... Thanks for your input guys

 

[bob johnson]

Re: 1998 90hp SPL running warm, voltage too

nomally the thermostat doesnt open till over 140 degrees..and running at 150 isnt a bad thing...

even though once the t-stat open the temps should fall right after....but may climb back up if you stay in the throttle....

is this something that is specifically DIFFERENT than before??

bob

 

[skiffinNH]

Re: 1998 90hp SPL running warm, voltage too

hey bob, yeah, its definitely different...the temp used to climb up to 140 while under way, then quickly dropped back down after slowing down and then idling...dropping way down...would extra warm lake water be making a difference? The water temp in the lake is now up over 80...didnt know if that makes a difference. Also, should I only be getting the 14.5 volts out of my motor? Is 17ish something to be concerned about?

 

[ondarvr]

Re: 1998 90hp SPL running warm, voltage too

The voltage and temperature should rise at different rates unless it is the voltage causing the high temp reading.

The voltage should go up in direct relastionship to the RPM,s or very close. The temp should take some time to increase and lag behind the RPM's.

The other thing is it shouldn't "sneeze", that's a sign of it running lean, lean will create more heat. It may need to have the carbs cleaned.

 

[bob johnson]

Re: 1998 90hp SPL running warm, voltage too

very warm lake water will definately have an eeffect on your cooling system..

I dont know much about electrical issues and certainly cant diagnose many of them....

I know my cars voltage guage spikes upwars a little as I rev the motor!!!

but there is something else in the car that keeps that from hurting anything..

good luck

bob

 

[skiffinNH]

Re: 1998 90hp SPL running warm, voltage too

thanks for all the help guys. I am going to check my battery connections and clean my carbs prior to anything else. Im just afraid of destroying any of my electronic components with the excess voltage. If there's any other input on my situation, I'm all ears. Thanks