Guest Posted March 15, 2002 Share Posted March 15, 2002 Greetings! I have a '72 GS 350 convertible with an all-original drive train. The engine was rebuilt in '84, though that's only about 18k miles ago. Last summer the radiator boiled over - the coolant got so hot that it came out of the over flow container (and made quite a racket). In response, I replaced the radiator (which was leaking), water pump (which was leaking), radiator cap, heater control valve, all hoses, and I flushed the system (the Prestone garden hose operation) no less than three times over the course of about 9 weeks. I also installed a digital temperature gauge, that I monitor like a hawk. Now, my questions: What temperature should I be running? How hot should the engine get after I turn the key off? I run down the road at 200, and will reach 210/15 if I'm at a stop light. After I turn off the car, the engine temp will reach 240/50. Should I be worried, or is this about right? Thanks in advance for the help!<P>-Morgan Allen<BR> '72 Buick GS Convertible Link to comment Share on other sites More sharing options...
Guest Posted March 15, 2002 Share Posted March 15, 2002 <A HREF="http://www.v8buick.org/" TARGET=_blank>http://www.v8buick.org/</A> Go here dude and ask............Ward Link to comment Share on other sites More sharing options...
Guest Posted March 15, 2002 Share Posted March 15, 2002 try running a 165 degree thermostat Link to comment Share on other sites More sharing options...
Guest Posted March 15, 2002 Share Posted March 15, 2002 I would say that your at the high end of an acceptable range. I remember reading a racing article where engines are at their peak efficiency just at the point before they are ready to boil over. I assume you got a correct water pump, fan, and shroud, and there are no headgasket leaks. You could try putting on an electic fan. My 60 Invicta overheated alot and the fan corrected it. But, there was no shroud, and the stock fan had only 4 blades. <P>Engine temp will rise when you shut the car off because the water is not circulating. Link to comment Share on other sites More sharing options...
Guest Posted March 15, 2002 Share Posted March 15, 2002 Try a new thermostat, and your car my have a fan clutch, which if original is probably shot for sure, they dont last very long. Link to comment Share on other sites More sharing options...
Guest Posted March 15, 2002 Share Posted March 15, 2002 You are fine at that temp.....the coolant does not boil at 212 degrees like water does because it is under pressure, which raises the boiling point. You say that the coolant went out of the overflow jug, which tells me that the system is being pressurized somehow by more than just temperature. I would be very leary that you have a cracked head/head gasket that is allowing exhaust into your antifreeze during driving, pressurizing the system. Your antifreeze would be dingy and smell a bit of exhaust if this is the case. Link to comment Share on other sites More sharing options...
Guest Posted March 15, 2002 Share Posted March 15, 2002 Hello. I've done some research in the past on the 455 motor. Aftermarket water pumps come with 2 styles of vanes on the impellers. One "style" has fins that do not extend all the way down the impeller. the other "style" has the fins that run all the way to the outer edge of the impeller. I am not sure if this is the case on the 350 motor however. I would imagine that it is a very good possibility however. Also, I would agree that running a lower temp thermostat and make sure your fan shroud is attached properly. I've also used a flex fan with great success. if you get a black one, you will never even notice it is aftermarket. Additionally, make sure you have the correct mix of antifreeze and water. If you want more info about the vanes on the impeller, write back and I can give you the name of the rebuilder that clued me in on that!!<P>Bob Link to comment Share on other sites More sharing options...
Guest Posted March 18, 2002 Share Posted March 18, 2002 Thanks for all the help! Some more information that might help: during that same time I replaced the fan clutch, thermostat (185 degrees), shroud, added a fan spacer, and added an electric fan - everything improved the temperature slightly, but no significant help. I'm interested in the exhaust into the coolant system theory...any additional thoughts/info about that? Thanks again for all the help!<P>-Morgan Allen<BR> '72 GS Convertible Link to comment Share on other sites More sharing options...
Guest Posted March 18, 2002 Share Posted March 18, 2002 Are you in central Ohio?? I am going by your "Hilliard" name.....that is a suburb here. If so, let me know and I'll pass on my phone number and you can call me regarding your overheating problem. Link to comment Share on other sites More sharing options...
Guest Posted March 19, 2002 Share Posted March 19, 2002 make sure your carb is not running too lean. if it is your engine will run hotter. Link to comment Share on other sites More sharing options...
Guest Posted March 19, 2002 Share Posted March 19, 2002 have you checked your engine timing?my 1972<BR>skylark ran hot when the timing was off Link to comment Share on other sites More sharing options...
Guest Posted March 27, 2002 Share Posted March 27, 2002 you might want to start back at the basics. try checking antifreeze and water mixture and do a pressure check, remember if there is not proper pressure then the boiling point is lower. take out the thermostat and boil it in a pot on the stove.place a kitchen thermostat in to make sure it opens at the proper temp.(also the suggestion to put in a 165 is a good one) look for restrictions,is the coolant flowing properly? do you have a.c? do you have heat? many summer driver onlys may never use it. check your heater core for flow.(in odd situation such as yours i might connect the two hoses together. you mentioned you have a fluse kit in. use the connection to put the two hoses together. some times just putting on the heat you might see a large difference. i asked about a.c. because u may have a vacuum accuated gate. it could be bad. i hope its nothing major. good luck Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now