Cruisers Forum
 


Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on Cruisers Forums. Advertise Here
 
Thread Tools Search this Thread Rate Thread Display Modes
Old 03-11-2012, 06:22   #1
Marine Service Provider

Join Date: Oct 2009
Location: In the U.S.
Boat: FP Tobago 35 [sold]
Posts: 426
2GM20F Temperatures

Does anyone know what the correct engine temperature should be on this engine?

Since I have no temp gauge, will be using an infrared laser to check the engine temp.

Should I be checking the heat exchanger or the block itself for the best check? I assume they should be about the same.

Thanks!
__________________
Mark (It's Irie - Sailing Blog)
The Wirie AP+ and The Wirie pro - Long Range Marine WiFi and 2/3/4G Systems
kiltym is offline   Reply With Quote
Old 03-11-2012, 06:50   #2
cruiser

Join Date: Aug 2011
Location: Tampa Bay area
Boat: Hunter 31'
Posts: 5,731
Re: 2GM20F Temperatures

Quote:
Originally Posted by kiltym View Post
Does anyone know what the correct engine temperature should be on this engine?

Since I have no temp gauge, will be using an infrared laser to check the engine temp.

Should I be checking the heat exchanger or the block itself for the best check? I assume they should be about the same.

Thanks!

I have a temperature gauge (and the same engine). My engine runs consistently at 160 degrees. I understand that's a little low but the mechanic assures me it's hot enough. Even running it up to red line, the temp doesn't vary, to the point that I wondered if it was really reading ...

until two days ago.

We were moving my boat to its new location, and a lot was going on ... and I forgot to open the seacock.

After we'd been underway a few minutes I looked at the exhaust -- and she wasn't pumping water! Since the engine is barely a year old and I had very recently changed the impeller, I realized -- the seacock was closed. I have just started doing that routinely and haven't put a hook by it yet for the keys ...

Looked at the temp gauge and it was up to 180. So I had multiple clues, passed the helm over to my friend, went below and opened the seacock, and within five minutes the temp was back down to 160.

Oh I take that back I have a 3ym, not 2. On my old engine, which had major overheat problems, I tried a laser heat gun and found that it was really hard to read the same spot each time. If you're going to go that route, I suggest that once you've found the hottest spot, which you can use the gun to do, you mark it, so you read the same spot each time.
Rakuflames is offline   Reply With Quote
Old 03-11-2012, 07:16   #3
Registered User
 
Sailmonkey's Avatar

Join Date: Sep 2009
Location: Houston
Boat: ‘01 Catana 401
Posts: 9,626
Re: 2GM20F Temperatures

I would suggest you shoot at something like the thermostat housing. The heat exchanger is likely to be cooler than engine temp, and sections of the block may not have coolant in them. The thermostat housing is where the thermostat regulates the temperature from anyway.

Just a wild guess, that engine should run between 160°F and 180°F under load.
Sailmonkey is offline   Reply With Quote
Old 03-11-2012, 07:39   #4
Moderator
 
noelex 77's Avatar

Cruisers Forum Supporter

Join Date: Jul 2007
Boat: Bestevaer.
Posts: 14,678
Re: 2GM20F Temperatures

It is certainly worth doing this even if you have a temperature guage to establish some baseline results.
I think most freshwater cooled diesels will be reasonably similar.
Maine sail has a great article on this:
Engine Temp Monitoring & Over Heating Baseline Assessment Photo Gallery by Compass Marine at pbase.com
noelex 77 is offline   Reply With Quote
Old 03-11-2012, 07:45   #5
cat herder, extreme blacksheep

Join Date: Jul 2008
Location: furycame alley , tropics, mexico for now
Boat: 1976 FORMOSA yankee clipper 41
Posts: 18,967
Images: 56
Re: 2GM20F Temperatures

my 2qm20h runs at 130-140 f. they run cool, as per my yanmar dealer/distributor in san diego. i dont know running temps for fresh water cooled yannies, but i am sure your yannie man does.....
zeehag is offline   Reply With Quote
Old 03-11-2012, 07:55   #6
Registered User

Join Date: Dec 2008
Location: Oriental, NC
Boat: Mainship Pilot 34
Posts: 1,461
Re: 2GM20F Temperatures

I just shot my 3gm30f (same engine, one more cylinder) with an IR gun at wot rpm. Realize that water temps here in Oriental have nosedived recently and were in the mid to upper 50s.

The temperature at the water pump housing stabilized at about 180 after running 5 minutes at wot. It probably would have been 200 or so at normal summertime water temps.

The temp immediately dropped to 160 or so when I backed off to low cruise speed.

David
djmarchand is offline   Reply With Quote
Old 03-11-2012, 09:52   #7
Registered User
 
CCBullseye's Avatar

Join Date: Sep 2012
Location: Virginia, up river from Chesapeake Bay
Boat: Cape Cod Shipbuilders Bullseye
Posts: 106
Re: 2GM20F Temperatures

It has been several years since I owned a 2GM20F, but it seems to me that it was suppose to run pretty warm with fresh water, like 185. They are made differently than the raw water cooled engines which are suppose to run much cooler. The best place to test the water temperature is where the sensor is located, right on top of the thermostat housing. You can pick up a sensor with a gauge to test it.
CCBullseye is offline   Reply With Quote
Old 03-11-2012, 17:09   #8
Eternal Member
 
Chief Engineer's Avatar

Join Date: Aug 2006
Location: North of Baltimore
Boat: Ericson 27 & 18' Herrmann Catboat
Posts: 3,798
Re: 2GM20F Temperatures

To give you a picture....aim the gun at the intake line and then at the line leading to the exhaust elbow.....that will give you coolant temp and differential
Chief Engineer is offline   Reply With Quote
Old 03-11-2012, 17:39   #9
cruiser

Join Date: Aug 2011
Location: Tampa Bay area
Boat: Hunter 31'
Posts: 5,731
Re: 2GM20F Temperatures

Quote:
Originally Posted by CCBullseye View Post
It has been several years since I owned a 2GM20F, but it seems to me that it was suppose to run pretty warm with fresh water, like 185. They are made differently than the raw water cooled engines which are suppose to run much cooler. The best place to test the water temperature is where the sensor is located, right on top of the thermostat housing. You can pick up a sensor with a gauge to test it.

Mine (new engine, only about a year old) has never run to 180 except the other day when I forgot to open the seacock. 160 is what I get consistently, all the time, at all RPM's. I've paid attention to it because I had such major overheat problems with the old engine... oy vey!
Rakuflames is offline   Reply With Quote
Old 03-11-2012, 18:22   #10
Moderator Emeritus
 
roverhi's Avatar

Join Date: Aug 2005
Location: Carlsbad, CA
Boat: 1976 Sabre 28-2
Posts: 7,505
Send a message via Yahoo to roverhi
Re: 2GM20F Temperatures

Is the engine salt water cooled or freshwater cooled through a heat exchanger. If its salt water cooled, it should be run under 150 degrees to keep salt from cystalizing and blocking the cooling passages. A freshwater cooled engine should run hotter but probably less than 200 degrees
__________________
Peter O.
'Ae'a, Pearson 35
'Ms American Pie', Sabre 28 Mark II
roverhi is offline   Reply With Quote
Old 04-11-2012, 04:29   #11
Marine Service Provider

Join Date: Oct 2009
Location: In the U.S.
Boat: FP Tobago 35 [sold]
Posts: 426
Re: 2GM20F Temperatures

Quote:
Originally Posted by Rakuflames View Post
Mine (new engine, only about a year old) has never run to 180 except the other day when I forgot to open the seacock. 160 is what I get consistently, all the time, at all RPM's. I've paid attention to it because I had such major overheat problems with the old engine... oy vey!
I appreciate the info but as you stated, you have a different engine.
__________________
Mark (It's Irie - Sailing Blog)
The Wirie AP+ and The Wirie pro - Long Range Marine WiFi and 2/3/4G Systems
kiltym is offline   Reply With Quote
Old 04-11-2012, 04:31   #12
Marine Service Provider

Join Date: Oct 2009
Location: In the U.S.
Boat: FP Tobago 35 [sold]
Posts: 426
Re: 2GM20F Temperatures

Quote:
Originally Posted by roverhi View Post
Is the engine salt water cooled or freshwater cooled through a heat exchanger. If its salt water cooled, it should be run under 150 degrees to keep salt from cystalizing and blocking the cooling passages. A freshwater cooled engine should run hotter but probably less than 200 degrees
It's freshwater cooled.

Thanks everyone for your responses, all helpful.
__________________
Mark (It's Irie - Sailing Blog)
The Wirie AP+ and The Wirie pro - Long Range Marine WiFi and 2/3/4G Systems
kiltym is offline   Reply With Quote
Old 04-11-2012, 04:37   #13
Marine Service Provider

Join Date: Oct 2009
Location: In the U.S.
Boat: FP Tobago 35 [sold]
Posts: 426
Re: 2GM20F Temperatures

Quote:
Originally Posted by Chief Engineer View Post
To give you a picture....aim the gun at the intake line and then at the line leading to the exhaust elbow.....that will give you coolant temp and differential
Intake line of the seawater or the coolant into the heat exchanger?

And what would this differential show me?

The hose leading to the elbow is the "warmed" sea water. If I measure the seawater intake it will tell me the temp difference but not sure what this value really tells me, except that some amout of heat is going out the exhaust.
__________________
Mark (It's Irie - Sailing Blog)
The Wirie AP+ and The Wirie pro - Long Range Marine WiFi and 2/3/4G Systems
kiltym is offline   Reply With Quote
Old 04-11-2012, 05:25   #14
Registered User
 
Cotemar's Avatar

Community Sponsor

Join Date: Dec 2007
Boat: Mahe 36, Helia 44 Evo, MY 37
Posts: 5,731
Re: 2GM20F Temperatures

kiltym,

This may help you monitor both engines at the same time. Works great, been using them for a few years now.

http://www.cruisersforum.com/forums/...tml#post654749
Cotemar is offline   Reply With Quote
Old 04-11-2012, 05:30   #15
cruiser

Join Date: Aug 2011
Location: Tampa Bay area
Boat: Hunter 31'
Posts: 5,731
Re: 2GM20F Temperatures

Quote:
Originally Posted by kiltym View Post
I appreciate the info but as you stated, you have a different engine.

Sorry, I thought we had the same one. I read 20, not 30.
Rakuflames is offline   Reply With Quote
Reply

Tags
2gm, 2gm20

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Advertise Here


All times are GMT -7. The time now is 14:04.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.