Efi 5.7 ideal idle temp, cool waters

[Shabah180]

After 10 minutes of idle from start up, in your opinion is it bormal to see gauge temp of 170-175?

 

[khe]

Mine reads 168-170. 5.7 EFI (Throttle body injected). Your readings could be OK - has it always run in that temp. range? When was the last time you changed the water pump impeller? The reason I ask is that when the impeller starts to fail, you'll see a slightly elevated temp. but not overheating.

 

[Shabah180]

170 at just after warm up? I thought it eas supposed to be 140-155. 170 maybe at wot

 

[alldodge]

After 10 minutes of idle from start up, in your opinion is it bormal to see gauge temp of 170-175?

If you have closed cooling then yes (don't remember what you have)

 

[Shabah180]

If you have closed cooling then yes (don't remember what you have)

Hey buddy!! Ok sorry, a friend called me hes on the water right now, doesnt have access to i ternet. Raw water cooled, efi, he just asked me if it was normal as he just bought the boat. Mine is carburated 95 350 5.7 which idles 140-155 and never higher than 170.

Hes saying gauge reads 170 10 min sfter start up. Gauges arnt completely reliable either but should be close. I told him i though thats hot for cooler waters at idle prior to running it on the water.
I just didnt want to jump the gun but typically it could be a impeller or manifold issue no?
Well inguess it could be lots of things, seeing as he has no base line to go off, no temp lazer to check against gauge accuracy.

 

[Scott Danforth]

its EFI. EFI motors run a 160 degree t-stat.

carbed motors run a 140 degree t-stat

cant compare temps between a carbed motor and an EFI motor unless both of them are running heat exchangers (and then both run 160 degree t-stats)

 

[Shabah180]

its EFI. EFI motors run a 160 degree t-stat.

carbed motors run a 140 degree t-stat

cant compare temps between a carbed motor and an EFI motor unless both of them are running heat exchangers (and then both run 160 degree t-stats)

No pardon the confusion, his is an efi.

 

[Shabah180]

its EFI. EFI motors run a 160 degree t-stat.

carbed motors run a 140 degree t-stat

cant compare temps between a carbed motor and an EFI motor unless both of them are running heat exchangers (and then both run 160 degree t-stats)

Scott are you able to explain what the difference is in a 140 and a 160 devree t stat?

 

[ingalp01]

One thermostat allows cooling water to circulate through the engine at 140 degrees, the other opens at 160 that's the only difference.

 

[Scott Danforth]

Scott are you able to explain what the difference is in a 140 and a 160 devree t stat?

one opens 20 degrees higher than the other.

so on one, you would see between 140 and 150 on your dash gauge. on the other you would see between 160 and 170 on the dash gauge

 

[Shabah180]

one opens 20 degrees higher than the other.

so on one, you would see between 140 and 150 on your dash gauge. on the other you would see between 160 and 170 on the dash gauge

Thanks for that guys!

 

[tpenfield]

I assume that your friend is back on land now. I imagine that the guy was asking about the temperature with concern of it rising too far, too fast. :noidea:

My boat (with closed cooling) gets to 165-170 within about 10 minutes idling an at no wake speeds. On land running on the muffs, it is more like 15+ minutes to get up to temperature. I attribute the difference to great water flow at idle speed from the hose/muffs and little exhaust back pressure on land.

 

[JoLin]

its EFI. EFI motors run a 160 degree t-stat.

carbed motors run a 140 degree t-stat

cant compare temps between a carbed motor and an EFI motor unless both of them are running heat exchangers (and then both run 160 degree t-stats)

Not necessarily. My 2014 RWC Merc Reman, 4bbl carb, came with a 160. My normal warmed-up idle temp is 170-175, and I read 175-180 at speed. Never varies.

 

[Shabah180]

I assume that your friend is back on land now. I imagine that the guy was asking about the temperature with concern of it rising too far, too fast. :noidea:

My boat (with closed cooling) gets to 165-170 within about 10 minutes idling an at no wake speeds. On land running on the muffs, it is more like 15+ minutes to get up to temperature. I attribute the difference to great water flow at idle speed from the hose/muffs and little exhaust back pressure on land.

Thanks ted, i know it was a spur of the moment question, and yes he pulled the boat out and is going to do an impeller change the t-stat.
It could be the gauge, impeller, manifolds or it could be nothing.
It was just to get info on an "average" running temp on a 350 efi raw water. 10min after start up, Out of all the placed to go, you fella's on here have a wealth of good information. Very foutunate to have fella's take time from their day to explaine stuff!