Engine temp
Engine temp
Lady's and gentlemen we have a problem. Engine temp went up today setting off alarm and motor went to limp mode. I have a 2014 220 with a Volvo V8 270. I changed the impeller this spring. I run fine all summer so far until today. Now for a bit of today's insight with was around 10 miles from the marina when we get the call my FIL had been transported to ER critical care unit. My wife was on board so I floored it all the way back. When I was 100 yards from the marina is when the alarm went off. We put the boat in the slip and took off. FIL is in Sable condition and while sitting here I thought I would see what all of your thoughts are?
Re: Engine temp
What did the temp go up to?
Very possible you just picked up a bag or something that blocked the water intake. Trim up the drive and see if you see anything fall off.
Glad the FIL is ok. My mom passed away this last December and we went through a lot of ambulance trips in the previous year.
Very possible you just picked up a bag or something that blocked the water intake. Trim up the drive and see if you see anything fall off.
Glad the FIL is ok. My mom passed away this last December and we went through a lot of ambulance trips in the previous year.
2017 R5 350HP Mercruiser Bravo III
Northridge, CA
Big Bear Lake, CA
South Lake Tahoe, CA
Northridge, CA
Big Bear Lake, CA
South Lake Tahoe, CA
Re: Engine temp
That happened to me once, I was running hard and the temp was fine then all of the sudden the buzzer was going off. I don’t remember what the engine temp went up to but I throttled back put the boat in reverse for a few seconds and then back to forward. As soon as I started moving forward the temp started to drop. I never saw anything behind the boat but I’m sure I picked up something that covered the fresh water intakes.bruceb58 wrote: Sat Jul 10, 2021 6:15 pm What did the temp go up to?
Very possible you just picked up a bag or something that blocked the water intake. Trim up the drive and see if you see anything fall off.
Glad the FIL is ok. My mom passed away this last December and we went through a lot of ambulance trips in the previous year.
Re: Engine temp
Salt water or fresh water?
If salt, could be scale and corrosion in manifolds and risers.
I wouldn’t worry about the temperature. Limp mode should be well below the damage point.
If salt, could be scale and corrosion in manifolds and risers.
I wouldn’t worry about the temperature. Limp mode should be well below the damage point.
2003 262 8.1 Volvo
- Krob1114
- Vice Admiral

- Posts: 1874
- Joined: Sun Jun 09, 2019 8:03 am
- Location: Greer’s Ferry Lake, AR
- Contact:
Re: Engine temp
Welcome to out Cobalt family.
Glad you FIL is in stable condition.
Hopefully the previous posts are correct and problem will be solved. We had similar problem with speedometer not working on our previous boat. Tube that measured water was blocked with trash.
Glad you FIL is in stable condition.
Hopefully the previous posts are correct and problem will be solved. We had similar problem with speedometer not working on our previous boat. Tube that measured water was blocked with trash.
2019 Cobalt R3 @ Greers Ferry Lake, AR
Home in Hernando, MS
Home in Hernando, MS
Re: Engine temp
I had a similar problem last year. We had unusual aquatic plant growth in our marina due to zebra mussels filtering the water so more sunlight makes it to the bottom. Anyway, my VP350 always runs at 161F and on this day it ran up over 180F and sounded an alarm. I slowed down and then put the boat in reverse and motored backward a bit. I assume it was plant growth on the intake because the problem went away and hasn't returned. I replace the impeller annually.
2019 Cobalt R3 - V8/350 - Ebony Hull w/ Knock Out Red Edge Stripe
Re: Engine temp
Our temp goes up about 10 degrees after an extended run and then quickly go back to idle. It cools back to 162 in less than a minute.
2020 CS23
The Kids Made Me Do It
The Kids Made Me Do It
-
sailor55330
- Vice Admiral

- Posts: 1268
- Joined: Thu Feb 01, 2018 4:37 pm
- Contact:
Re: Engine temp
I had a VP 5.0 of about the same era as your 270. Seems like it ran all day long at 175, regardless of speed or rpm, so it makes me think the engine was runnign above that. On that boat, I actually had an impeller hose slip off at speed and the tem spiked to almost 250 for about 60 seconds before I saw the gauge (no buzzer). Put the hose on and she cooled right down and kept running.
On my 2016 5.3, she idles and 162, runs wide open and tows at 165 and drops within 30 seconds back to 162. Water temp does not make a difference except in cold water (65) it takes slightly longer to warm up, but not much.
On my 2016 5.3, she idles and 162, runs wide open and tows at 165 and drops within 30 seconds back to 162. Water temp does not make a difference except in cold water (65) it takes slightly longer to warm up, but not much.
- jhnmdahl
- Vice Admiral

- Posts: 2365
- Joined: Tue Jan 06, 2015 5:11 pm
- Location: Twin Cities, MN
- Has thanked: 1 time
- Been thanked: 1 time
- Contact:
Re: Engine temp
Make sure there's no water leaking anywhere, inspect the water inlet for debris, and inspect/change the impeller for starts. I've had an experience similar to Sailor's, and it's unlikely you've done any damage. Please do let us know how it turns out,
John
John
Administrator of the www.cobaltchat.com Cobalt boats community forum
2015 210 (Volvo Penta 5.7L V8-225)
2015 210 (Volvo Penta 5.7L V8-225)
Re: Engine temp
Update on what happened. Apparently at some we was running in shallow water. Sucked up some sand and clogged the water out line. In doing so it also damaged my exhaust thermostats. My initial check of the impeller was it looked new since I just changed it this spring. However due to the water out line clogged up the impeller was still trying to pump water through the motor and in turn the metal shaft broke away from the rubber impeller. It would turn just enough to pump small amount of water which when I took hose off it looked like it was working fine. Then when under load it would just spin on the shaft. So the fix was clean out sand at all the ports and change out impeller. All is good and back up and running. Motor runs good. Water temp is good for 3 weeks now.
- AsLan7
- Fleet Admiral

- Posts: 11458
- Joined: Sat Jul 29, 2017 10:58 am
- Location: Erie PA
- Been thanked: 1 time
- Contact:
Re: Engine temp
.
Great to hear S73.
… and thanks for the follow up too.
Great to hear S73.
… and thanks for the follow up too.
2002 Cobalt 262
&
2005 Cobalt 263
496 MagHO
(sold )
Erie, PA
Currently boatless (for now)
will fly for food
(CChat moderator)
&
2005 Cobalt 263
496 MagHO
(sold )
Erie, PA
Currently boatless (for now)
will fly for food
(CChat moderator)
- Krob1114
- Vice Admiral

- Posts: 1874
- Joined: Sun Jun 09, 2019 8:03 am
- Location: Greer’s Ferry Lake, AR
- Contact:
Re: Engine temp
Another reason we never get below 10 foot depth.Scsmith73 wrote: Fri Aug 20, 2021 4:32 pm Update on what happened. Apparently at some we was running in shallow water. Sucked up some sand and clogged the water out line. In doing so it also damaged my exhaust thermostats. My initial check of the impeller was it looked new since I just changed it this spring. However due to the water out line clogged up the impeller was still trying to pump water through the motor and in turn the metal shaft broke away from the rubber impeller. It would turn just enough to pump small amount of water which when I took hose off it looked like it was working fine. Then when under load it would just spin on the shaft. So the fix was clean out sand at all the ports and change out impeller. All is good and back up and running. Motor runs good. Water temp is good for 3 weeks now.
2019 Cobalt R3 @ Greers Ferry Lake, AR
Home in Hernando, MS
Home in Hernando, MS
- Big Block Power
- Fleet Admiral

- Posts: 17930
- Joined: Sat May 07, 2016 8:05 pm
- Location: Neenah,Wi
- Contact:
Re: Engine temp
That's the Max depth of our lakeKrob1114 wrote: Sat Aug 21, 2021 5:15 amAnother reason we never get below 10 foot depth.Scsmith73 wrote: Fri Aug 20, 2021 4:32 pm Update on what happened. Apparently at some we was running in shallow water. Sucked up some sand and clogged the water out line. In doing so it also damaged my exhaust thermostats. My initial check of the impeller was it looked new since I just changed it this spring. However due to the water out line clogged up the impeller was still trying to pump water through the motor and in turn the metal shaft broke away from the rubber impeller. It would turn just enough to pump small amount of water which when I took hose off it looked like it was working fine. Then when under load it would just spin on the shaft. So the fix was clean out sand at all the ports and change out impeller. All is good and back up and running. Motor runs good. Water temp is good for 3 weeks now.
03Cobalt220 8.1gxi DP
"Kids in Tow2"
"Pot The Jus" Originator :-)
Neenah Wi
#ItsBu'sfault
#FARCON Marine CC Core!
"Kids in Tow2"
"Pot The Jus" Originator :-)
Neenah Wi
#ItsBu'sfault
#FARCON Marine CC Core!
Re: Engine temp
There wouldn't be a boat on Blackhawk lakeBig Block Power wrote: Sat Aug 21, 2021 7:57 amThat's the Max depth of our lakeKrob1114 wrote: Sat Aug 21, 2021 5:15 amAnother reason we never get below 10 foot depth.Scsmith73 wrote: Fri Aug 20, 2021 4:32 pm Update on what happened. Apparently at some we was running in shallow water. Sucked up some sand and clogged the water out line. In doing so it also damaged my exhaust thermostats. My initial check of the impeller was it looked new since I just changed it this spring. However due to the water out line clogged up the impeller was still trying to pump water through the motor and in turn the metal shaft broke away from the rubber impeller. It would turn just enough to pump small amount of water which when I took hose off it looked like it was working fine. Then when under load it would just spin on the shaft. So the fix was clean out sand at all the ports and change out impeller. All is good and back up and running. Motor runs good. Water temp is good for 3 weeks now.![]()
CS23
Who is online
Users browsing this forum: No registered users and 19 guests



