Engine Coolant Temp alarm

[DandyAndy]

Hi all

This is my first post after being a member for some time!.. typically any questions i have are usually already answered .

so here is my first post and i'm sure its been answered before but i have yet to find it!

I have:

2009 Malibu Wakesetter 23' LSV

158 Hrs on the engine (just serviced at 130)

This past weekend we were out to get our first real ride of the season (nor cal - Delta) and the wedge would not go down as we anticipated.. (ended up going up and down but did not sound the deploy buzzer as usual) so i looked under the dash to check fuses.. as it was our first ride of the season maybe it was time to replace a few.. i noticed as i unplugged a 5 amp cricket fuse an alarm almost instantly popped up.. "engine coolant temp".. the boat was off and only on aux power... thought it was odd myself.. then while filling our ballasts to wake surf it popped up again! the temp reading was at 181 degrees... then it goes away and jumps back down to 169-171 and holds steady.. then it will randomly jump up to 180 and kick the sensor again and go away.. it only happened a few times all day but it got me wondering...

am i chasing an electrical issue or a temp issue? did i cause an issue with the computer when i pulled that in aux?

what is the typical temp for these boats? even 180 sounds to be in the "normal" range?

I look forward to some responses and yes i'm a little green around the ears when it comes to boats but i figured this group would point me in the right direction!

thanks

Andy

[GreenMan]

Hi, Andy.

When you say the indicated temperature 'jumps' up and down, do you literally mean it snaps up and then down instantaneously? If so, you have some sort of electrical fault since the coolant can't change temp that quickly let alone the sender respond that quickly.

Since the same thing occurred when you unplugged that 5 amp fuse, maybe that's the first area to hunt around.

Are you sure it is now properly seated in the socket?

Are you sure the installed fuse is OK? Try swapping it with another known good fuse.

Does any further jiggling around there incite the issue again? Loose wires behind or something.

If the indicated temp drifts up and down over, say 30 seconds or something, you probs have a cooling issue like failing impeller etc. Is it engine speed related?

Your description sounds more like the first scenario though.

Regards, Stephen.

[grandude]

Look into a re route kit from Indmar. It is a set of 6 hoses that will regulate your temp to a rock steady 160 as well as helping protect your cats from major damage if left as is. You might call customer service and give them your engine number and they can confirm if you need this, but it sounds like a classic symptom.

The routing of the coolant hoses on engines of that time frame had water flow that was supposed to be cooling the cats restricted until the thermostat opened which can let the cat temp spike then dump cold water in on top of it. Bakes will be aware of this kit as well. It's a fairly easy task with some basic mechanic skills.