58 runs hot

[Steve K.]

This 1958 runs at 200 degrees with a 160 thermostat (verified with a laser temp sensor). My friend's 1957 runs 184-188 deg all day long here in Florida. I have verified timing and have installed a new 7# radiator cap. The possibilities left are radiator, water pump, head gaskets installed wrong, and corroded/scaled block inside. All of these solutions are pricey and labor intensive. What do you all think? Live with it or throw parts at it? Add an electric faf, or a 5-7 blade fan?
Thanks,
Steve

[andy strauss]

Re: 58 runs hot

A quick test for the radiator is to get car to operating temp,then check for temp differences on the radiator.Compare the top to the sides and the sides to the bottom etc.If you find a spot that is cooler than the rest that spot is most likely restricted.As far as a scaley block goes,remove water pump and see if you can see any scaling,possibly use a borescope if you have access to one.I have never tried but I would assume there is some sort of chemical additive that could help.

Andy

[andy strauss]

Re: 58 runs hot

A quick test for the radiator is to get car to operating temp,then check for temp differences on the radiator.Compare the top to the sides and the sides to the bottom etc.If you find a spot that is cooler than the rest that spot is most likely restricted.As far as a scaley block goes,remove water pump and see if you can see any scaling,possibly use a borescope if you have access to one.I have never tried but I would assume there is some sort of chemical additive that could help.

Andy

[Terry R. Payton]

Re: 58 runs hot

Steve-I went thru the same thing restoring my '58. Painful experiance because I went crazy trying to figure it out.This board helped alot, but I still could not figure it out. Anyway, after alot of $$ spent..including hi-perf water pump. aluminum radiator, 6-blade fan installed and countless opinions, it turned it to be nothing but 3, count them..3 defective or just not working properly thermostats! what are the chances of this? Anyway, I now have a 160 in and the motor runs precisely @ 160! finally. good luck

[Terry R. Payton]

Re: 58 runs hot

Steve-I went thru the same thing restoring my '58. Painful experiance because I went crazy trying to figure it out.This board helped alot, but I still could not figure it out. Anyway, after alot of $$ spent..including hi-perf water pump. aluminum radiator, 6-blade fan installed and countless opinions, it turned it to be nothing but 3, count them..3 defective or just not working properly thermostats! what are the chances of this? Anyway, I now have a 160 in and the motor runs precisely @ 160! finally. good luck

[Gary Chesnut]

Re: 58 runs hot

Steve, try it without a thermostat and see if it makes a difference. If it does, suggest use a Robert Shaw 160 degree thermostat which you can get from Summit. The Robert Shaw thermostats allow alot more water flow throughput. Gary....

[Gary Chesnut]

Re: 58 runs hot

Steve, try it without a thermostat and see if it makes a difference. If it does, suggest use a Robert Shaw 160 degree thermostat which you can get from Summit. The Robert Shaw thermostats allow alot more water flow throughput. Gary....

[Kris Schmalenberg]

Re: 58 runs hot

I have a 58 that ran at 180 (with a 180 stat) all day long until last year. My problem turned out to be a small crack where the tube running from the top rad tank meets the filler neck. No coolant would escape but the rad would not keep pressure. My suggestion is to pull your rad and have it flow and pressure checked. A pain to do but the cost is minimal and then you can hopefully rule the rad out.

[Kris Schmalenberg]

Re: 58 runs hot

I have a 58 that ran at 180 (with a 180 stat) all day long until last year. My problem turned out to be a small crack where the tube running from the top rad tank meets the filler neck. No coolant would escape but the rad would not keep pressure. My suggestion is to pull your rad and have it flow and pressure checked. A pain to do but the cost is minimal and then you can hopefully rule the rad out.

[John H.]

Re: 58 runs hot

99% of all cooling problems end up being radiator-related (assuming thermostat is OK, shroud and fan OK, and lower rad hose not collapsing due to spring being corroded away). Nobody ever expected our radiators to last this long, and it doesn't take much internal scale in the tubes to reduce their heat transfer efficiency by 30%-50%. I had my '57 270 original radiator re-cored when I restored it five years ago, run a Robertshaw #330-180 180-deg. thermostat, and it runs at 180 all the time, in traffic or on the highway. I'd consider having your radiator re-cored, and run a Robertshaw 180 thermostat; 160 will work too, but it won't let the oil get hot enough to boil off blow-by contaminants and condensation in the pan. Don't even bother with a "flow test" at a radiator shop - all that will tell you is that it isn't plugged; what matters is heat transfer, and that's a function of how much scale is insulating the coolant from the inside of the tubes.

[John H.]

Re: 58 runs hot

99% of all cooling problems end up being radiator-related (assuming thermostat is OK, shroud and fan OK, and lower rad hose not collapsing due to spring being corroded away). Nobody ever expected our radiators to last this long, and it doesn't take much internal scale in the tubes to reduce their heat transfer efficiency by 30%-50%. I had my '57 270 original radiator re-cored when I restored it five years ago, run a Robertshaw #330-180 180-deg. thermostat, and it runs at 180 all the time, in traffic or on the highway. I'd consider having your radiator re-cored, and run a Robertshaw 180 thermostat; 160 will work too, but it won't let the oil get hot enough to boil off blow-by contaminants and condensation in the pan. Don't even bother with a "flow test" at a radiator shop - all that will tell you is that it isn't plugged; what matters is heat transfer, and that's a function of how much scale is insulating the coolant from the inside of the tubes.