Engine temperature with AC on?

David Harris

Expedition Leader
Gents,
Is there a "knockout" somewhere on the block that has access to the Jacket water?

**I bought a gauge on the way home from work after reading this thread...:sombrero:

Best,
DB

Best to put it in the heater hose from the manifold for the reasons posted above.

David
 

burn_e

Adventurer
I've put the sensor in the upper radiator hose since I wanted the temperatur of the water leaving the block (no thermostat - removed). More important the heater hoses and the intake heater hoses are not functional any more. No more heater - really no need for it here!

Question: is there water flowing through the heater pipes when the heater is off?
 
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David Harris

Expedition Leader
I've put the sensor in the upper radiator hose since I wanted the temperatur of the water leaving the block (no thermostat - removed). More important the heater hoses and the intake heater hoses are not functional any more. No more heater - really no need for it here!

Question: is there water flowing through the heater pipes when the heater is off?

Without a thermostat the radiator hose is fine. However, there it is reading the water at it's coolest temperature in the cycle. The water still flows through the heater hoses, but by bypasses the core when the heater is off, I believe.
 

High Center

Adventurer
Best to put it in the heater hose from the manifold for the reasons posted above.

David

Got it- I skipped right through that part of the post. Your rational behind the heater hose location makes sense.

This will make a good Sunday project.

Best,
DB
 

burn_e

Adventurer
Without a thermostat the radiator hose is fine. However, there it is reading the water at it's coolest temperature in the cycle.

Didn't get this. Didn't the water just left the engine block and entered the upper rad hose at this point (and isn't very much cooled down?)

Am I on the wrong track here???
 

David Harris

Expedition Leader
Didn't get this. Didn't the water just left the engine block and entered the upper rad hose at this point (and isn't very much cooled down?)

Am I on the wrong track here???

Yes. Excuse me. Your right. The uncooled water exits the motor via the upper radiator hose. So, this location is good for a sensor as well, as long as the thermostat doesn't stick closed, in which case the coolant in the engine could overheat before the temperature sensor in the upper hose can register it, since coolant won't be flowing through there with the thermostat closed. The advantage to the heater hose from the manifold is that this point is not dependent upon an open thermostat for flow. Hot water from the engine flows through the heater loop independent of the thermostat. I have attached a flow diagram below.
 

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TexasTJ

Climbing Nerd
Well Went camping about an hour and a half from home this weekend and the Temp stayed around 195 to 210 on the Highway. As soon as a stopped at a light though it started to creep up to a high of 230. I'm going out pull the radiator out next weekend and take care of that. OH and the Stock gauge never moved from center. I had one scary moment. The first time I had the gauge on with the lights it ran all the way to the peg at 280 pulled out the light and DOWN it came back to normal so I'm going to need to find a new way to light it.
 
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JEFFSGTP

Observer
sounds like the wiring is wrong....does the guage have a seperate lead for the backlight?...if so try wiring that into one of the dash lights that can be dimmed/brightened with dash control...that should correct the problem (best guess...it just sounds like its crossfeeding into the guage side the way it's wired now.)
 

TexasTJ

Climbing Nerd
The light is a seprat lead on the gauge. I had just jumped it off the fuse box to get it working, so more than likely it is getting to much power. Im going to tap the stock gauge lighting this weekend.

Nate
 

David Harris

Expedition Leader
The light is a seprat lead on the gauge. I had just jumped it off the fuse box to get it working, so more than likely it is getting to much power. Im going to tap the stock gauge lighting this weekend.

Nate

Mine's a mechanical gauge, but I tapped the light into part of the headlight switch wiring.
 

TexasTJ

Climbing Nerd
Mine is mechanical just with a power lead to the light. I
just haven't looked up what wire to tap.
 

TexasTJ

Climbing Nerd
I could use a little help on how to get the Fan Cluch off the water pump. I have a wrinch that will fit but How to I stop it from spining on the shaft?
 

David Harris

Expedition Leader
I could use a little help on how to get the Fan Cluch off the water pump. I have a wrinch that will fit but How to I stop it from spining on the shaft?

I use a long screw driver wedged against the bolts that hold the pulley on. Just takes a quick wack to the left on the handle of the wrench to break it loose. Then just spin it off. Some also wedge a rag between the pulley and the belt to provide resistance while breaking it loose.
 

burn_e

Adventurer
I use a long screw driver wedged against the bolts that hold the pulley on. Just takes a quick wack to the left on the handle of the wrench to break it loose. Then just spin it off. Some also wedge a rag between the pulley and the belt to provide resistance while breaking it loose.

Yep that's how it works. Just use a spanner instead of a wrench. More control and no parts to break off.
 

TexasTJ

Climbing Nerd
I have now done a head gasket and have a new radiator. the fan cluch is new too. I've been driving the rover a week and all has been great. Ac off temps have been between 185 and 195. Ac on from 196 to 205. Idle at stop light 205. Today in a Parking garage it got start going up to 210ish. Just want to make sure I'm ok
 
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