Engine Running Temperature Thermostat

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JohnForr
Posts: 45
Joined: Mon Sep 01, 2014 6:46 pm
Location: Punta Gorda, Fl

Engine Running Temperature Thermostat

Post by JohnForr »

What temperature does your Universal35B run at?
I live in South West Florida and the water temps are pretty warm and right now are close to 80 degrees.
Mine has been running at about 180 degrees. The thermostat is supposed to be a 160 degree stat.
John & Mary Jane Forr
Punta Gorda, Fl
Hull #007
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TBOT422
Posts: 424
Joined: Sun Jun 26, 2011 5:36 pm
Location: Clearwater, FL

Re: Engine Running Temperature Thermostat

Post by TBOT422 »

John,

180 degrees is a little high. Probably an indication of a partially clogged heat exchanger or the beginnings of a leaking raw water pump. We just got back from a 3-week cruise from Tampa to Marco Island. Motored most of the time. Temperature was just over the 160 degree mark. A friend with another C350 noticed their boat was running a little hotter than normal (around 180) and found a leaking raw water pump. The mechanic ran an acid flush through the heat exchanger, then replaced the raw water pump and all was fine back around 165 degrees.

Good Luck
Gary & Janet
The Best of Times (Hull #422)
JohnForr
Posts: 45
Joined: Mon Sep 01, 2014 6:46 pm
Location: Punta Gorda, Fl

Re: Engine Running Temperature Thermostat

Post by JohnForr »

Thank you very much. I suspected 180 was too high. I am glad you responded. I am now going to check the thermostat, raw water pump and clean out the heat exchanger. I have not checked my heat exchange zinc since last November, so that gets done also.
John & Mary Jane Forr
Punta Gorda, Fl
Hull #007
wolfe10
Posts: 587
Joined: Mon Dec 11, 2006 2:58 pm
Location: Ft Myers Florida

Re: Engine Running Temperature Thermostat

Post by wolfe10 »

Because gauges can be inaccurate, I have an alternate suggestion for determining if it is time to address your cooling system:

Does the temperature go up between when the engine is warmed up and, say 3/4 throttle? full throttle? If so, then yes, that indicates that the cooling system is not able to remove the BTU's needed to keep the engine in thermostatic control. If the gauge is where it has always been and only at wide open throttle does the gauge move, you are still OK.

Now, if you are getting ready for a long trip, yes Preventive Maintenance may be a very good idea. If doing that, do all of it: Change raw water impeller, boil out heat exchanger and install new end gaskets, replace thermostat and replace engine coolant. Be sure to bleed the air from the cooling system, including at the water heater. I also rerouted the raw water strainer to raw water pump hose for a straighter run and removed the 90 degree fittings at the water pump by rotating the raw water pump clockwise. Also, then rerouted the raw water to heat exchanger hose. 90 degree turns and extra feet of hose detract from cooling system efficiency.
Brett Wolfe
C350 #180
"Vindaloo"
Ft Myers FL
nybor
Posts: 248
Joined: Sun Jan 06, 2013 7:55 am

Re: Engine Running Temperature Thermostat

Post by nybor »

My 1 cents

When I bought my boat and ran the engine, the temperature ran a bit above 180. So I changed the thermostat and now it runs a hair over 160

dave
JohnForr
Posts: 45
Joined: Mon Sep 01, 2014 6:46 pm
Location: Punta Gorda, Fl

Re: Engine Running Temperature Thermostat

Post by JohnForr »

Thanks. We checked the thermostat and it is a 160 degree F one. It appears to be working fine. When putting thermostat back in we are having a hard time getting it to stop leaking around when the gasket is. I put in a new gasket and that leaked so now we are trying gasket sealer.
John & Mary Jane Forr
Punta Gorda, Fl
Hull #007
wolfe10
Posts: 587
Joined: Mon Dec 11, 2006 2:58 pm
Location: Ft Myers Florida

Re: Engine Running Temperature Thermostat

Post by wolfe10 »

Might be a good idea to check and make sure the thermostat housing and head are not warped.

Easy for any part removable from engine. Get a sheet of glass, sheet of 600 and sheet of 2000 grit wet dry sand paper. Try the 2000 first. If the part is warped, start with courser and work to the finer. On the head, a sanding block or similar (again a large smooth surface) and sandpaper.

Learned this trick on VW carburetors where the aluminum bases warped. Fixed a lot of them for 30 minutes work instead of hundreds of dollars.
Brett Wolfe
C350 #180
"Vindaloo"
Ft Myers FL
JohnForr
Posts: 45
Joined: Mon Sep 01, 2014 6:46 pm
Location: Punta Gorda, Fl

Re: Engine Running Temperature Thermostat

Post by JohnForr »

I am going to see if the liquid gasket works.. That will be tomorrow. And then I will examine the top of the housing. There is a lot of gunk on that housing.
John & Mary Jane Forr
Punta Gorda, Fl
Hull #007
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