How.much coolant flow is too much? Still hot

[Birdflu]

Instead of too much flow...what about a restriction in the system? If there's a restriction somewhere, it will flow just enough to keep the temps down while idling or at lower speeds. With the car at cruising speed at higher RPM's then the restriction cannot flow enough coolant to meet the demand. Just a thought...

[oldcarnut]

Did you do the test that several of us said to try before taking it apart?

No I have not yet.  Not because I was ignoring it but because I wanted to see what I had and if it had issues and also the right stuff to begin with .  My crank is a 7" and wp a 6".  Pump was an 8 blade non AC.  I checked inside the housing for blockages and didn't see anything.  One item I have is that pulleys were changed to chrome and they slip.  The pwr steering was constantly squealing until I changed to a different style belt and roughed up the grooves a little.  The belt had seemed to be loosened again so I'm wondering if part of the problem is when at speed the belt is slipping on the pump as well as the steering but just not hearing it. The inlet is in the passenger side unlike it usually is.  I will do the rpm test for sure after I order an ac pump since I have added ac to it and put a regular steel pulley back on the pump and see what happens then.  

[Paul G]

 

I fought overheating for a very long time. Does the engine have a huge overbore? Like .060", it can add to overheating. Too much timing at cruise, like when vacuum advance pulls in can add to overheating.

How much total timing are you giving the engine and at what RPM is it all in? How much additional vacuum advance timing is added at cruise? Is the exhaust quiet enough to hear detonation at cruise? Lots to do, little time to do it.

[c00nhunterjoe]

Paul, im running a .060 over block that is also filled and i dont run hot on the street. Dont see that being the issue in this case.

[b5blue]

FYI: I'm .60 over 440, Mopar R.R. cam, had 346 heads now "Sidewinder aluminum" with 4BBL, HP EXH. Mans, Moroso high flow T stat, 26" 3 row with cowl and direct drive factory fan off stock pulleys with aftermarket A/C running 180-190 in 97 degree heat with A/c on. 

[oldcarnut]

Trying to get to the bottom of this between other projects. Changed the crank pulley to a stock steel and got rid of some slip.  Installed a Flowkooler hi flow pump and hiflow thermo.  Ran the engine sitting 2k and still getting 215-220. Called the gauge mfg and got a tested verified sending unit and compared to mechanical gauge-ok.  Sprayed bottom of carb-no change.  Ran engine to 2k until hot and killed ignition and pulled plugs.  Pictures of plugs below.

[oldcarnut]

Pump

[b5blue]

I recommend getting a Temperature Gun. For about ten bucks you can point and shoot the system for readings. I got one and it's come in handy many times. Sorry for your PIA, I've had this same issue. (Why I have direct drive fan.)

[c00nhunterjoe]

The plugs look a touch lean to me. Have you verified the timing at the overheat rpm yet?  Do you have a stock waterpump? Most times i have seen high flow pumps used, it causes problems. X2 on the temp gun. Check the rad in different spots and look for cold spots, then also check inlet vs outlet temperature.

[Petebell68]

No one has mentioned this so I'll try . I have a 68 Charger RT it would get hot cruising around town and even highway .
Looked at everything and then  remembered the rubber seal at front of hood and the seal at the firewall hood area .
Ordered the two pieces put them on and no matter how hot or how long I'm stuck in traffic runs perfect now .

[c00nhunterjoe]

I dont have either of those seals on my car.

[Petebell68]

Lean and timing then

[c00nhunterjoe]

Lean and timing then

The attached photos of his plugs do not indicate a lean condition. Timing perhaps, but i still feel the hiflow aftermarket styled pump needs to go.