Running temperature

[Just Limin']

I'm constantly worrying about running temperatures. A throwback to my old sailboat's engine. On my R25SC with a 150 Yanmar, it seems to run mostly at 196 degrees. We cruise at 6-8 knots. Of course, it increases when we go faster. It this about right?

Thanks,

Bill Eggert
Annapolis

 

[knotflying]

Sounds about right. I have the 4BY2-180 I get 196 degrees around 2,500 RPM and when WOT around 201 degrees. Of course water temperature will give a slight variation.

 

[Hydraulicjump]

Same 4BY2-180 as knotflying, but slightly cooler running temps. Seems pretty consistent in the PNW, San Francisco Bay and Delta.

1800 rpm 188-89, 44 psi
3600 rpm 190-191, 77psi
4000 rpm (WOT), 193 (highest ever), 78 psi

Been tracking this closely for 260 hours and replace impeller regularly.

 

[HRowland]

The thermostat in our BY2 series engines starts to open at 190F and is not fully open until 205F. Modern engines are designed to run hotter to help meet EPA emission requirements.

Also note that just because our electronics display temperature with 1 degree resolution does not mean it is that accurate. The sensor is an analog temperature to resistance device, the electronics then converts this to a digital value. There are tolerances at both steps. Once you know what is normal for your engine you can be aware of a deviation and take action.

Howard

 

[workingdogs]

Observe departure from normal . Just like airplanes ! Very well expressed !

 

[nzfisher]

I have heard that the 4 cyl yanmar diesel runs at around 240 f when in the auto it was originally designed for. While this information was off a web blog, it might be worth taking into consideration and verifying when worrying about high temps in our boats with impeller failures and clogged intakes. I am currently hard pressed to get mine over 201 at 3400 rpms in 55 degree water.

 

[PhilR]

My 4BY2 180 runs 205 deg. at 80 % throttle. The alarm goes off around 225-230 deg. That's what happened when my defective coolant hose let go back in 2012.

 

[Gin]

Hmmm. Wondering what the Volvo users are experiencing. I should have been logging the temp and psi info, but haven't. I will start. Meanwhile, my impressionist sense is that the new Volvos (a) run a bit cooler (temp = 178 to 182 when fully warmed up, depending on how much load) and psi is higher (78 to 90, and often erratic). Any Volvo owners that can offer observations?

As I said, I plan to start a log ...

Gini

 

[Lenny and Louise]

We have one year old volvo on our R25SC. Runs about 178 at our usual 1900 turns. Oil pressure varies but around 70 psi seems ususal.

 

[BobR]

My Volvo D4 runs 185 degrees at cruise.

Bob

 

[Larrynbarb]

Lenny and Louise, your numbers are the exact same as ours on our 2013 25SC. But my WOT rpm is 3000, nothing like Hydraulicjump's 4000.

 

[Gin]

Larrynbarb, WOT at 3000 seems low. We get 4150 (fully loaded, but other circumstances ideal -- like freshly painted bottom) on our R27. Check your engine manual to see if 3000 is what the specs call for.
Gini

 

[Larrynbarb]

Tnx Gini, I'll have to re-read it. Do you have the Volvo engine?

 

[HRowland]

Per the Volvo-Penta web site, D3-150 is 3000 RPM max and D3-200 is 4000 RPM max.

Howard

 

[Gin]

Howard, good catch. We have the 200. Hence the WOT spec of 4100. Didn't expect such a difference for the 150hp model.

Gini