Temperature Guage-Trust or Not

[trymyluck]

Hi All
How many people only worry about water coming out the telltale as to running temperature of their outboard, I know thats all we ever worried about with the older motors.

Yep she's coming out;D

Nup no water there:'(

When we brought our current boat we noticed a couple of weeks after we brought it that the temperature gauge actually read about 30% cooler then the motor should but the motor temp seemed to be ok. I'd already serviced the lower end even though there seemed like plenty of water passing thru, That was an eye opener. Amount of water coming out the telltale increased heaps to the point I didnt need to look to know if i'm pumping water when i start the motor.:o:o

Knowing that the motor wasn't overheating or running too cold I didnt worry too much about where the gauge sat although I did change the thermotats just in case.

Then yesterday while running around Hervey Bay I looked down and the temperature was up to 90 to 95 instead of 65 to 70.:o:o Oh s#&t.
Quick check, plenty of water, motor didn't feel overly hot or smell like it was overheating so I just put it down to the gauge coming to life after hitting a bit of choppy crap.(Still in the dog house with the other half ::))

So the question is do you put much faith in the gauge or not. Sure was a lot less complicated when I didn't have a gauge and just checked that the telltale was flowing.:P Might have to convince the boss that we need to get one of those laser pointed thermometers for checking the bearings at work;);)

Mark

[Noelm]

I guess if you are so inclined, remove the gauge and just look at the tell tale "like in the good old days" or take the gauge for what it is, a GAUGE, not a be all to end all precision laboratory instrument, in some ways I guess you could have a gauge with no numbers on it at all, if it goes way further than it used to, then something is amiss and needs attention/maintenance.

[Spaniard_King]

Mark,

to back up the tell tale (as some times they block up) just put in a water pressure gauge.. easier than a temp gauge.

[FNQCairns]

At 95 deg the engine is usually stuffed (although the owner may not know it yet) so we can as best case anyway assume the gauge is incorrect at that reading. Still it's not impossible your engine was running too cool and now it's correct??? still if it where me i wouldn't let the guage or the engine get away with the difference you saw, track it down it may be nothing but it may not either.

I have no tell tail as the water pressure gauge is connected to the outlet, the cooler your engine runs but still within operating temperature the less problems you will have with water gallery buidup.

cheers fnq

[trymyluck]

Noelm That is exactly how I look at the gauge, an indicator that something has changed and needs to be checked.

Spaniard_King & FNQCairns What sort of Pressure gauge do you use, are they made for this application and do they come with the hardware to mount or are they just a standard gauge?

[FNQCairns]

Noelm That is exactly how I look at the gauge, an indicator that something has changed and needs to be checked.

Spaniard_King & FNQCairns What sort of Pressure gauge do you use, are they made for this application and do they come with the hardware to mount or are they just a standard gauge?

I have the standard Yamaha one, it comes with a water tube with an olive, a supplied (usually) fitting is inserted into the engine at a provided point (or you make one) and the tube fitted, I simply disconnected the pisser tube at the cowl jet forced the olive inside then zip tied closed.

It's nice to not have to look behind when on the water as i tear through some floating crap, happens lot's up here in the wet season.

Another idea is to fit one of these http://cgi.ebay.com.au/ws/eBayISAPI.dll?ViewItem&item=130283877361&ssPageName=MERCOSI_VI_ROSI_PR4_PCN_BIX&refitem=130272175127&itemcount=4&refwidgetloc=closed_view_item&refwidgettype=osi_widget&_trksid=p284.m185&_trkparms=algo%3DSI%26its%3DI%26itu%3DCR%252BUCI%2 6otn%3D4%26ps%3D42

I have one of these in my diesel 4wd and it is simply beaut! Have been planing on purchasing this marine one for the boat...many claim to look at a temperature gauge often enough to catch a damaging overheat in real time but they are ALL telling porkys.

cheers fnq