Thread: Is 225 too hot?

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Well my car has new gauges and a new temp sensor in the top of the engine. With my other old gauges and sensor my car ran under 200. But now the car maintains around 225. Will the new sensor and gauges make a difference, and if it stays at 225 all the time will it have effects long term?

My wife had an 81 Corvette it ran 220 I thought that was too hot, she called a Chevy dealer and they said it was normal. Check with a Chevy dealer and give them the engine numbers. On my 86 Elcamino the red area is 200 to 225. I would not want my street rod running at 225. Might add another electric fan to help bring it down.

Richard

Thanks for the info. Where are the numbers located on a block.....LOL!

1st it depends on what kind of motor and year it is as to the temp its gonna run. What size motor is it, also is it an EFI TBI TPI or carbed motor?

I think if the only thing that has changed is the sender and guage. One of the two gauges is off.

The block number should be on the passenger side just below the head, the alternator might make it hard to see if it’s on that side. The older 396 engines had numbers that gave the horsepower by the distributor passenger side. If you could tell the service manager at a Chevy dealer could tell you. I just thought I took it for granted it was a Chevy, maybe not though.

The newer engines, I'm lost so maybe another member can give you a better idea. Good luck, it's a pain to have an engine running hot.

Richard

It's a sbc 350 for now....LOL! I'm gonna put a 302 in her eventually.

If it is a 81 and up center bolt valve cover motor with , fuel injected TBI, or TPI, then they are supposed to run hotter. But at 225 on this style engine the external fan is supposed to kick on and cool it down to about 205, and not continually run at 225. If the motor is a pre 81 with valve cover bolts on the outer flange, then 225 is warm and even 200 is considered about as hot as you would want it to stay at on the pre 81 350 carbed motor.

My valve covers bolt like this one. Also I changed the oil to Mobil 1 recently. Synthetic oil shouldn't make the car run hotter I wouldn't think and if I have the radiator overfilled make any difference?

those are the pre 81 valve covers. synthetic should not make any difference. as long as you have a vented radiator filler neck, with a vent tube running to a puke tank, or right to the ground. Then It cant be over filled. And 99.9 percent of radiators made are vented. If it does not have a puke tank you need one. When the car is running (start from cooled down) Squeeze the upper radiator hose that goes to the thermostat housing. If it is tight and firm the thermostat is closed, as soon as it opens the hose will be softened and you will be able to squeeze it flat. check your temperature at that point to verify the themostats operating range. It should open at 190 or so for a carburated motor with the heads you have.

What type fan are you running, from a water pump pulley, or a radiator mounted unit? If its a pump mounted unit does it have a full shroud from the radiator to the fan blades? If not that may be your problem, and an additional radiator mounted fan might become a nessacary item, and cheaper in the long run to get, then modifying a shroud in a custom fit car like yours.

here is a pic of my puke tank set up from the filler neck.

Good advice mooneye777, It's nice when people can help one another, if a guy in the beginning gets a smart remark he my not ask again then it is one unhappy car guy.

We all hope you get it straighten out soon youther.

Richard

Originally Posted by mooneye777

those are the pre 81 valve covers. synthetic should not make any difference. as long as you have a vented radiator filler neck, with a vent tube running to a puke tank, or right to the ground. Then It cant be over filled. And 99.9 percent of radiators made are vented. If it does not have a puke tank you need one. When the car is running (start from cooled down) Squeeze the upper radiator hose that goes to the thermostat housing. If it is tight and firm the thermostat is closed, as soon as it opens the hose will be softened and you will be able to squeeze it flat. check your temperature at that point to verify the themostats operating range. It should open at 190 or so for a carburated motor with the heads you have.

What type fan are you running, from a water pump pulley, or a radiator mounted unit? If its a pump mounted unit does it have a full shroud from the radiator to the fan blades? If not that may be your problem, and an additional radiator mounted fan might become a nessacary item, and cheaper in the long run to get, then modifying a shroud in a custom fit car like yours.

here is a pic of my puke tank set up from the filler neck.

I started the car and I was able to squeeze the hose right away.

I do have a resivor tank and I also have an electric fan with a shroud.

With me being able to squeeze the hose as soon as I started it, does that mean that my thermostat is stuck open and that I should replace it?

Youther....Princeton WV is listed as elevation 2605 ft so water boils at appx 207.7 degrees F there. You could take your temp sensor out and put it into a container of water and boil the water....when the water begins to boil, the indicated temperature should be 207.7. Of course, you would also have to take your temp gauge along to the stove and rig up a 12 volt source to run it.

If the gauge/sender reads accurately, the next step is to inspect your installation. Did you change the position or location of the sender? Some folks mount the sender in a location where there is a trapped pocket of air that keeps the temp sendor tip from being in contact with the water. I've seen people put senders in some awful looking pipe adapters that insulated the sender....of course, these read low. One way to assure the absence of the air pocket is to burp the system by unscrewing the temp sensor after you fill the system (and it is still cold) so that a small bit of liquid escapes (to tell you that the air is gone).

You didnt say what brand of gauges you are using and if the sender matched the gauge brand.

hope this helps

mike in tucson

Originally Posted by robot

Youther....Princeton WV is listed as elevation 2605 ft so water boils at appx 207.7 degrees F there. You could take your temp sensor out and put it into a container of water and boil the water....when the water begins to boil, the indicated temperature should be 207.7. Of course, you would also have to take your temp gauge along to the stove and rig up a 12 volt source to run it.

If the gauge/sender reads accurately, the next step is to inspect your installation. Did you change the position or location of the sender? Some folks mount the sender in a location where there is a trapped pocket of air that keeps the temp sendor tip from being in contact with the water. I've seen people put senders in some awful looking pipe adapters that insulated the sender....of course, these read low. One way to assure the absence of the air pocket is to burp the system by unscrewing the temp sensor after you fill the system (and it is still cold) so that a small bit of liquid escapes (to tell you that the air is gone).

You didnt say what brand of gauges you are using and if the sender matched the gauge brand.

hope this helps

mike in tucson

Great info. I'm not technical enough to pull this off....LOL! I can pull off the sender and see if it is full.

As far as the sender and the gauges, the sender was not part of the gauges but is new. The gauges are TPI Tech gauges.

OOOOh...that may be your problem if you didnt buy a sender matched to the gauge. A temperature gage is really just a volt meter and the resistance calibration of the sender is matched to the full scale reading of the gauge.
In fact, there are several factory senders for Chevy with different resistances....check with your gauge manufacturer and they should be able to tell you the correct resistance.

Also, the grounding on a one-wire sender is thru the threads to the intake....dont use teflon tape or too much pipe goo and increase the resistance