Temp question

[lirex3]

First off... Hello everyone, I am new to this forum. I have a 2002 searay 225 weekender I purchased a few months ago that needed a repower. All done and boat runs great. I am seeing around 170 deg on my gauge and one riser is warmer than the other. I was not sure about that 170 temp so I swapped out the temp sender and new oem temp gauge. Still showing 170- 172 deg. I used a temp gun and it is showing 140 to 145 deg at multiple locations on the motor. Is that normal for a gauge to be off that much? I figured it may be calibrated that way from factory to give you a buffer zone so shut it down and not hurt a motor. Anyone see this same issue? Other than that I love this boat!!!

 

[lirex3]

Re: Temp question

Also I put about 40 hrs on the new engine and did my first oil change around 6 hrs of use.

 

[alldodge]

Re: Temp question

Welcome to the forum

You haven't mentioned what we are working on but I'll base my comments on an EFI engine. A temp of 170 isn't bad, cars run 180 to 200 so 170 is OK. Given that you probably have a 160 degree thermostat and then gauges are not calibrated, but it does sound like yours is fairly close. Now if you have carberated engines there may be an issue. If you can provide a bit more info our answers/question could change.

 

[lirex3]

Re: Temp question

Thank's AllDodge...

It's a 5.0 mercruser efi engine, and yes it has a 160 deg thermostat. I figured that 170 was ok, I read other sites and they have write ups that state 170 to hot. My truck runs 204 deg on really hot days and 199 is normal for it. I have a 2012 dodge ram 1500 with the 5.7 hemi. If I were to try a 140 deg thermostat being fuel injected it probably would run to rich is that correct? Also forgot to mention risers and manifolds are also new oem type mercruser. And everything in regards to cooling was replaced when I put the engine in, all parts replaced were either mercruser and quicksilver.

 

[alldodge]

Re: Temp question

Thank's AllDodge...

It's a 5.0 mercruser efi engine, and yes it has a 160 deg thermostat. I figured that 170 was ok, I read other sites and they have write ups that state 170 to hot. My truck runs 204 deg on really hot days and 199 is normal for it. I have a 2012 dodge ram 1500 with the 5.7 hemi. If I were to try a 140 deg thermostat being fuel injected it probably would run to rich is that correct? Also forgot to mention risers and manifolds are also new oem type mercruser. And everything in regards to cooling was replaced when I put the engine in, all parts replaced were either mercruser and quicksilver.

If your impeller is in good shape I wouldn't pay much mind with 170. If the temp was at 180 after cool down at idle then would check a bit closer. Your correct a 140 temp would be bad for a EFI motor, running rich, performance loss, carbon build up.

 

[lirex3]

Re: Temp question

Thanks AllDodge,

Impeller was also replaced.

 

[seilings]

Re: Temp question

Thank's AllDodge...

It's a 5.0 mercruser efi engine, and yes it has a 160 deg thermostat. I figured that 170 was ok, I read other sites and they have write ups that state 170 to hot. My truck runs 204 deg on really hot days and 199 is normal for it. I have a 2012 dodge ram 1500 with the 5.7 hemi. If I were to try a 140 deg thermostat being fuel injected it probably would run to rich is that correct? Also forgot to mention risers and manifolds are also new oem type mercruser. And everything in regards to cooling was replaced when I put the engine in, all parts replaced were either mercruser and quicksilver.

My boat comes with a Mercruiser 4.3L 262 cdi engine, and the manual says it uses 160 thermostat.
The temp gauge has 175 in middle, and it always stays at 175 after warm up on muffs or on water, or running under load.
So I thought the 175 is the normal operating temp for 4.3 Engine.

 

[lirex3]

Re: Temp question

Is your boat fuel injected or has a carb?