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ArtQ

ArtQ

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I have a 62 BT7. It was consistently overheating in traffic (showing 212 - 230 on the gauge and running extermely rough above 212) so I invested in having the radiator rebuilt, an extra row added and installed a new Moss six bladed fan. My mechanic also added a new 160 thermostat. The heater coolant connection has been disconnected so the extra tubing is not in the mix. During the rebuild process, we discovered that my temp. gauge was showing 10 - 15 degrees hotter than actual temp registered with a thermometer in the top radiator tank.

After all that work, while driving in about 75 degree sunny weather in traffic and with stop lights after about 45 minutes, the car still (according to the temp gauge) hits 212 while stopped but but goes back down to 190 while driving. While driving at about 50mph up a steep hill(about 1 mile or so) the temp gauge will climb to 212, but does recover to 190 fairly quickly. I'm running a 50-50 antifreeze mixture.

My question is, do I need to go back to the radiator guys and tell them, try again or is what I am experiencing fairly typical? What should I expect as a "normal" driving temp range.

Sorry for the length of this, but I wanted to make sure I included all the pertinent data.
 
--Hi Art Q. The first thing You need to do is get rid of that MOSS six bladed fan.They break and do not push enough cooling air. Moss had a recall on that fan some years ago don't know why they still push them. As a replacement,I suggest that you get what is known as a Texas cooler six bladed fan.Can't comment on the radiator but only a handfull of them know how to do them right.Additionally, a good block back flush may help the problem.---Fwiw--Keoke
 
It happens, and there's no set reason to what's causing the problem. Here's a couple of questions. Was the thermostat an original type, or from a local parts store? Are the timing and Carb mix set correctly? Did you install a new radiator cap? Did the engine get thoroughly flushed when they did the radiator work? Try dropping the mix way down (more water) and using water wetter. You could also try removing the bonnet and driving around. This would tell you if the problem is agravated by underhood temperatures.
 
[ QUOTE ]
I have a 62 BT7. It was consistently overheating in traffic (showing 212 - 230 on the gauge and running extermely rough above 212) ---- During the rebuild process, we discovered that my temp. gauge was showing 10 - 15 degrees hotter than actual temp registered with a thermometer in the top radiator tank.

----- the car still (according to the temp gauge) hits 212 while stopped but but goes back down to 190 while driving. While driving at about 50mph up a steep hill(about 1 mile or so) the temp gauge will climb to 212, but does recover to 190 fairly quickly. I'm running a 50-50 antifreeze mixture.

[/ QUOTE ]

It's still not clear to me if the temperatures, 190-212, are with the defective gage or are corrected/actual temperatures.

If they are with the gage that reads 15 degrees high, & actual temperatures are 175 to 197, there is not too much wrong.

Sorry if I am confused.

The fact that the temp goes back down when moving, indicates that the fan isn't doing as good a job as it could.

I personally feel that the variable pitch six blade fan sold by Norman Nock is much more effecient than the others & is indestructable. I could be wrong, but the last I heard, the Texas Cooler is no longer available. I won't go into how good or bad it is.
D
 
Yes, according to the NTAHC website the Texas Kooler is no longer available and having recently switched from the DW equivalent of it to the Nock flex fan I wholeheartedly second Dave's comment--though a bit high tech looking the flex fan definitely moves more air, decreases my operating temperature 5-10 degrees at low speeds and gives me greater ability to tolerate bouts of stop-and-go traffic. It did require a bit of grinding on the adapter plate to clear the nose of my water pump pulley.
 
/ubbthreads/images/graemlins/savewave.gif

Michael,a bit high tech looking?.That thing is just plain down right Ugly,in spite of its enhanced performance.---Keoke- /ubbthreads/images/graemlins/devilgrin.gif-- /ubbthreads/images/graemlins/grin.gif
 
Afriend of mine pulled all the core plugs while doing a rebuild. He then spent hours with probes etc pulling all the crap out of the block - including, he reckoned, casting sand. Hard work but worth it (when the engine is out)
 
I guess my basic uncomplicated question is what should I expect the "correct" running temp of a otherwise well running, 62 BT7 with a new radiator, added row and a new fan to be?
 
Here in Sunny Scotland. my BT7 always sits right on 190 unless it sits in traffic or goes much over 3000rpm in top, but even then it doesnt reach 212
 
[ QUOTE ]
I guess my basic uncomplicated question is what should I expect the "correct" running temp of a otherwise well running, 62 BT7 with a new radiator, added row and a new fan to be?

[/ QUOTE ]
To repeat my above statement:
"If the temperatures are with the gage that reads 15 degrees high, & ACTUAL temperatures are 175 to 197, there is not too much wrong." This is about as uncomplicated as I can make it.

You can stick a thermometer in the top tank to verify the temp gage readings.
D
 
[ QUOTE ]
Afriend of mine pulled all the core plugs while doing a rebuild. He then spent hours with probes etc pulling all the crap out of the block - including, he reckoned, casting sand. Hard work but worth it (when the engine is out)

[/ QUOTE ]

Yes the casting sand inside the Daimler V8 blocks is enough to choke a horse and must be dug out during a rebuild.There is no reason to suspect the Healey blocks do not suffer the same fate mine did too.---Keoke- /ubbthreads/images/graemlins/thumbsup.gif
 
Latest "JEGS" catalog has a large selection of external temp sensors for <$100. Good chance to check the actual temp and eliminate the gauge and factory sensor from the loop. Bob
 
[ QUOTE ]
I have a 62 BT7. It was consistently overheating in traffic (showing 212 - 230 on the gauge and running extermely rough above 212) so I invested in having the radiator rebuilt, an extra row added and installed a new Moss six bladed fan. My mechanic also added a new 160 thermostat. The heater coolant connection has been disconnected so the extra tubing is not in the mix.

[/ QUOTE ]

I believe that the prevailing wisdom is that it is better to OPEN the heater valve and allow the coolant to circulate through the heater, thereby providing more opportunity for the coolant to cool. I know that you don't want extra cockpit heat, especially when the engine is already running hot, but that's what you do for the extra little bit of cooling.

[ QUOTE ]
During the rebuild process, we discovered that my temp. gauge was showing 10 - 15 degrees hotter than actual temp registered with a thermometer in the top radiator tank.

[/ QUOTE ]

I wouldn't be too sure that that is an accurate measure of your coolant operating temp.

[ QUOTE ]
After all that work, while driving in about 75 degree sunny weather in traffic and with stop lights after about 45 minutes, the car still (according to the temp gauge) hits 212 while stopped but but goes back down to 190 while driving. While driving at about 50 mph up a steep hill (about 1 mile or so) the temp gauge will climb to 212, but does recover to 190 fairly quickly. I'm running a 50-50 antifreeze mixture.

[/ QUOTE ]

I'd change the coolant to a ratio of maybe 10 percent anti-freeze:90 percent water, assuming that freezing ambient air temps are not a concern.

[ QUOTE ]
My question is, do I need to go back to the radiator guys and tell them, try again or is what I am experiencing fairly typical? What should I expect as a "normal" driving temp range.

[/ QUOTE ]

Normal is difficult to define, although an operating coolant temp of about 180 is probably ideal. Nothing really wrong with 190, although I wouldn't want to see it get a lot above that very often.

In addition to changing your coolant mixture ratio, you should probably try installing a better fan, and checking mixture and timing.

[ QUOTE ]
Sorry for the length of this, but I wanted to make sure I included all the pertinent data.

[/ QUOTE ]

Bottom line: if you engine is not being damaged, and not running rough, and hoses are not bursting, and coolant is not escaping overboard, you don't really have an overheating "problem," you just have a hot-running engine.

You might also want to try adding a bottle of "Water Wetter" or similar product to the coolant. The usual advice about flushing the system is also sound.
 
Proper timing will keep the engine cooler too. I run an original fan and 50/50 coolant and I usually run 190 and 200 in traffic. But I seldom drive in temps over mid 90's. because of the altitude here (6500 ft) I run more advanced than normal 15 BTDC. I'm not sure if the thinner air makes a difference in cooling as it does in carb adjusting.
 
[ QUOTE ]


--Hi Art Q. The first thing You need to do is get rid of that MOSS six bladed fan.They break and do not push enough cooling air. Moss had a recall on that fan some years ago don't know why they still push them. As a replacement,I suggest that you get what is known as a Texas cooler six bladed fan.Can't comment on the radiator but only a handfull of them know how to do them right.Additionally, a good block back flush may help the problem.---Fwiw--Keoke

[/ QUOTE ]
/ubbthreads/images/graemlins/savewave.gif
Hey Editor Reid!,Didn't you forget to Quote some of the "Pertinent Data"??.--Keoke---- /ubbthreads/images/graemlins/grin.gif
 
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Hey Editor Reid!,Didn't you forget to Quote some of the "Pertinent Data"??.--Keoke---- /ubbthreads/images/graemlins/grin.gif

[/ QUOTE ]

I know better, but I'll bite: what "pertinent data"?

(I ain't got to show you no steeking pertinent data!) /ubbthreads/images/graemlins/grin.gif
 
----Keoke--- /ubbthreads/images/graemlins/lol.gif
 
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