temperature on Mercruiser 4.3 LX

[ste80]

hi guys, anyone check the temperature on motor wile it is running?
when i'm running with my motor my temp instrument show 65/70 degrease that it sound good and i don't have any issue. (only smalldifference between left and right riser)
last weekend when i was running motor at 3600 rpm, i checked with laser termomether the real temperature of all components
i found [in °C]
motor 65
pipes from pump to motor 65
intake manifold 70
left riser 49,7
right riser 36.7

the only issue i noted in the intake manifold in the exaust crossover port where during running i sow 150/180 deg

when i was running slowly (1000 rpm more or less i was reading 80/90 deg)

the hot temperature is just where the bolt of the intake manifold is located and only in the area where the crosover goes. if i check in the cloosest area i have 70°C also wile motor is running. ( i was also wander if it was a wrong measurament)
what do you think is it normal? someone said yes, mayber it can be reasonable becuse there is no water i think in that area

thanks

 

[Scott06]

hi guys, anyone check the temperature on motor wile it is running?
when i'm running with my motor my temp instrument show 65/70 degrease that it sound good and i don't have any issue. (only smalldifference between left and right riser)
last weekend when i was running motor at 3600 rpm, i checked with laser termomether the real temperature of all components
i found [in °C]
motor 65
pipes from pump to motor 65
intake manifold 70
left riser 49,7
right riser 36.7

the only issue i noted in the intake manifold in the exaust crossover port where during running i sow 150/180 deg

when i was running slowly (1000 rpm more or less i was reading 80/90 deg)

the hot temperature is just where the bolt of the intake manifold is located and only in the area where the crosover goes. if i check in the cloosest area i have 70°C also wile motor is running. ( i was also wander if it was a wrong measurament)
what do you think is it normal? someone said yes, mayber it can be reasonable becuse there is no water i think in that area

thanks

View attachment 409483

you outline normal temps 65-70 C (is 148-158F)

if has the exhaust cross over and is 80 c that is normal in my opinion.

with the laser what is the thermostat housing ? I assume it is 65-70 C?

sound like all is running well.

when was last time water pump impeller was changed in drive? I'm not saying you need to change it , just good preventative maintenance.

 

[ste80]

you outline normal temps 65-70 C (is 148-158F)

if has the exhaust cross over and is 80 c that is normal in my opinion.

with the laser what is the thermostat housing ? I assume it is 65-70 C?

sound like all is running well.

when was last time water pump impeller was changed in drive? I'm not saying you need to change it , just good preventative maintenance.

You missed one number 1 in front of the reading .
Thermostat house is 65
Motor 65 all part 65/70
Only part very hot is the bolt near crossover 150/180°c
Motor is rebuilted totaly.
Block machined
Head machined
Allmost component are new. Motor just has like 10 hours
All intake manifold is 70
Only the bolt near crosover is really hot

 

[Scott06]

You missed one number 1 in front of the reading .
Thermostat house is 65
Motor 65 all part 65/70
Only part very hot is the bolt near crossover 150/180°c
Motor is rebuilted totaly.
Block machined
Head machined
Allmost component are new. Motor just has like 10 hours
All intake manifold is 70
Only the bolt near crosover is really hot

you are fine then

 

[ste80]

you are fine then

Do you think 180° in that point is ok?
Tks

 

[Scott06]

Do you think 180° in that point is ok?
Tks

Yes that’s why I said you are fine

Check out the exhaust temp close to the manifolds at the exhaust ports … that will be much hotter

 

[ste80]

Yes that’s why I said you are fine

Check out the exhaust temp close to the manifolds at the exhaust ports … that will be much hotter

Agree . Also because there is no whater in that part .
Thanks

 

[Fun Times]

Do you think 180° in that point is ok?
Tks

What was the cross over pipe middle part temp reading? I recall seeing mid to near high 230+ Fahrenheit range many times and yes, the threaded parts of the tube seemed a bit higher too...It's the hottest part of the engine when all is normal and that is why they have the heat protected sleeve over it.... Makes you jump when you touch it.

 

[ste80]

What was the cross over pipe middle part temp reading? I recall seeing mid to near high 230+ Fahrenheit range many times and yes, the threaded parts of the tube seemed a bit higher too...It's the hottest part of the engine when all is normal and that is why they have the heat protected sleeve over it.... Makes you jump when you touch it.

When i move from that bolt it goes down as you said , it goes down obviously also when i'm 1000 rmp, but once i go 3600 rpm temp goes high.
Wich sleaves you are refering at? I do not have nothing there (mine doesn't have any tube outside ot inside) crossover pirts is on the intake manufold (i put one picture from network)