Coolant Alarm Sounding.

[Speedboat]

I've got a 2013 Mercury 175hp Pro XS Optimax Serial # 2B018990 model 175P73EY. Recently I was at the lake and had the alarm sound on my mercury. Switching the motor off I found I believed the cause to be the coolant system. I took the boat to the Mercury tech to have the motor diagnosed and fixed. I believe the cause for the alarm sounding is that the water pump and thermostat is due to be replaced. My question how involved is it to replace these two components? My mercury tech will be performing these task I was just interested so I would have an idea as to the cost of these repairs. All this said if the water pump and thermostat are the needed repairs.

[Idaho Sandman]

$200 ish in parts and a couple hours labor.

[Savage]

Wrong boards Sir your motor is not a 3.0 liter.

[SilverFox579]

Since it's a 2.5L I can tell you servicing the water pump and inspecting thermostats (there are 2) is something anyone with a little patience, genuine Mercury service manual for your engine (by serial number), and some mechanical aptitude can do themselves. You'll likely pay ~ 2hrs labor plus parts. Make certain your mechanic also inspects/cleans the compressor strainer - very important.

I've done all service on my engine since new and it is still running the original t-stats. Don will probably move this to the 2.5L forum for you.

[Riccochet]

T-stats are easy. Water pump is a bit more involved since you need to pull the lower unit, and have a stable platform to work on it.

Dealer is going to charge you around $50 per t-stat and probably $100 for the water pump kit, and 2-3 hours for the work.

Like mentioned you'll also want the compressor strainer cleaned. And while they're at it might as well rebuild the poppet valve since it's the last piece of the cooling system puzzle. Should be about $50 in parts and another hour of labor, but worth having done if it hasn't been done before.