Water temp gauge reading

Daniel McCurdy

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I don't have a real water temperature gauge yet and was wondering where on the factory gauge I should start getting concerned. I was towing in 3rd gear wot 45mph 2750rpm and it started getting a little warm about to the A on the gauge. I didn't have the overheat light come on but I have no idea if it works.
 

Slicknik

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Too many variables

Turbo or N/A?
stock fan and clutch? Modified?
OEM radiator? Old/new? Brass or aluminum ?
What coolant you running? 50/50?

My best guess is....

Should hear the fan come on by the L , my aftermarket ones show about 220-225 when the dummy gauge hits the A ,

It’s fine if it climbs but if you don’t hear the fan ingauge you got a problem
 

Daniel McCurdy

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Engine was originally na has hypermax turbo kit. Has stock everything. original radiator. I never did here the fan start howling so don't know if it's not working or it just didn't get hot enough
 

Cubey

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Get a $30 Equus water temp gauge from O'Reilly if money is tight. Can't really help with the factory gauge reading.
 

Jake_IN

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When i was towing my C600 it was basically a 2hour trip with the pyrometer pinned at 1100 degrees (flat land i could eventually hit 60-65 but the slightest incline and I was back at 50-55mph). I was sitting between the A and the L the entire time. Engine didn't skip a beat, if anything it was in need of a good long hard run like that. It ran noticeably better for a long time after that drive.


This is a screenshot from a video i recorded while towing it. You can see the water temp over next to the A.
QEP0OWb.jpg



P2xZaOF.jpg
 

subway

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Get a $30 Equus water temp gauge from O'Reilly if money is tight. Can't really help with the factory gauge reading.

unfortunately this, some have corelated temperatures where around R is this temp and M is this temp but they vary truck to truck so it is more an individual ref and not completely reliable. If you want to know what is going on plug an aftermarket gage in and you will get your temperatures.
 

Bradd Barmettler

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Agree with Cubey above, best way to know your engines reality is put in aftermarket gauges.


It has been mentioned in other posts on this site that the dash cluster (Especially in the earlier IDI's) is using more of engine check light sensors to give a pseudo gauge reading, than a real variable sensor and appropriate gauge. So they tell you that you have some sort of oil pressure, some coolant temperature, some vacuum, but really cannot tell you with accuracy how much. Also there was issues with resistors in the dash cluster that can wreak havoc and give false readings. Adding to that is some of your sensors by now are quite old and may not function well. Again giving false readings. For all of this many put in aftermarket gauges to see exactly what is going on to help prevent a failure of the engine.


Take my truck, my brake light keeps coming on and off. Lack of vacuum or low brake fluid can set this light. (As well as electrical problems.) Likely the vacuum sensor is going bad and setting off my brake light. However my vacuum pump is working fine and my vacuum measures correctly. The sensor (Big can on the fender well.) looks to be original. So this puts me in a position of not knowing if this is a false positive or a real positive. So frustrating when you drive around and don't know which it is. I will fix that issue but first need to see what is available or if I have to get a used one. If used that could put me back to here months or a couple years from now. However with a aftermarket vacuum gauge and some comfort my brakes are not leaking fluid, I would know that this is a false positive, not an actual problem.


So sadly the only real way to know what your engines health is to put in aftermarket gauges.


All the best!
 

Daniel McCurdy

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Thanks for the suggestions. I plan on getting a nice isspro gauge so I know the reading should be good.
 

Cubey

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Thanks for the suggestions. I plan on getting a nice isspro gauge so I know the reading should be good.

Others report that the cheap Equus gauge is just as accurate, but go for it if you feel better with Isspro. My RV has ancient Isspro gauges for it's EGT and boost. I put Equus mechnical for water temp and it seems accurate. Temps dropped about 10 degrees with a new fan clutch (old was weak) and thermostat.
 

Trevtron

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Equus gauges have worked for me for the last few years, more accurate than relying on your dash gauges.
 

Daniel McCurdy

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also i may have a concerning problem. iv searched the truck down and cant find any water leaks anywhere but over time the water level goes down. so the leak is either very slow and impossible to find or something internal could be wrong
 

gnathv

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You may have a leak that is small enough that it evaporates before it can drip. Is your radiator cap in good shape (rubber gasket that seals) Do you see signs of condensation in oil?
 

Cubey

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Where's the best spot on the engine to put the temp sensor

Usually people put it in the water temp warning light port. I put it there on my F250. On my RV, I put it in the factory water temp gauge port because it was a bit easier to reach. Either works.
 

Daniel McCurdy

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You may have a leak that is small enough that it evaporates before it can drip. Is your radiator cap in good shape (rubber gasket that seals) Do you see signs of condensation in oil?
Everything is in great shape. I gave the engine and radiator a very through flushing. New thermostat, radiator cap, hoses, and hose clamps so all of that is good. Don't really know what condensation in the oil looks like but it's solid black no signs of milkyness. I do know at night when the lights are shining on the exhaust it looks like quite a bit of smoke but you can't tell at all during the day
 
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