What temperature should it run at?

3

34 ford

Cadet
Joined
Sep 20, 2011
Messages
28
Hi,
I have a 1988 Bayliner 2155 with a OMC 350 .
Just replaced exhaust manifolds risers and outdrive pump impler(all newParts).
Running it in the driveway with water muffs and garden hose.
It idles at temperature at 140 degrees. I put it in forward gear and run it up to 2500rpm
to 3000rpm for about 10 minutes, it climbs to 175 to 180 degrees, then let it idle back down
and it drops back down to 140 to 150 degrees.
Is that normal for just running it off the garden hose? Or should I take it to the Lake,
and get a better reading?
The exhaust and risers do get really hot to touch when up to 175 to 180 degree.
Thanks for any help.
 
Reinell-BRXL-191

Reinell-BRXL-191

Petty Officer 1st Class
Joined
Apr 18, 2012
Messages
295
Re: What temperature should it run at?

If the thermostat is working properly, the temp while running should be around 160-180 - this of course depends on the water temp being fed to the engine... here where I live, the water coming out of the hose is 95-98 degrees! But what you are describing as temps from running to idle seem in the proper range and would not concern me at all - my lake is 85 degrees right now, and the temp on the motor sits right at the 160 mark most of the time

Just remember that a garden hose normally flows in the 5-8 gpm range - At higher rpm, I am sure the impeller can move a lot more than it can be fed by a hose... this will increase water temps
 
Nivekt

Nivekt

Chief Petty Officer
Joined
May 13, 2009
Messages
481
Re: What temperature should it run at?

I have a '79 OMC 260 motor which is the GM 350. It idles on the hose at about 155F and on the lake around the same. When running around at WOT for a while it will get up to 170 but thats it. That is with a lake temp of 81F. My boat type is in my sig and the original factory Cobalt manual states that if the temperature reaches 180 the engine is overheating and needs to be shut off and trouble shooted. I just replaced the temp. sender, thermostat and exhaust manifolds/risers before I took the aforementioned temp. readings.
 
southkogs

southkogs

Moderator
Staff member
Joined
Jul 7, 2010
Messages
14,796
Re: What temperature should it run at?

Get a reading on the lake. It should be the same as in your drive, but it isn't always. I've always targeted 160? as an operating temp, and I won't run at speed if it's heating over that.
 
cr2k

cr2k

Captain
Joined
Mar 19, 2009
Messages
3,730
Re: What temperature should it run at?

175* is about max you want to see, anything above that I would start looking for cause.
 
You must log in or register to reply here.
Top