Overheating too

...In MY Opinion 210F Degrees Is NOT Overheating for the Cleveland, It Is Normal!

What is the Ambient Temperature?
Is the Engine New and is still being Broken-In?
Is the Coolant a 50/50 % with anti-boil?
Is the Brass Restrictor Plate Installed, Along with the Correct Skirted Robertshaw Thermostat?
Has ALL of the Air Been Bled out of the System?
Is the Radiator CAP Holding Pressure?
Are the Electric Fans turning In the Correct Direction/Rotation...AND Are Getting FULL CURRENT, Directly From the Battery? This List could Go On and On!!

WHY It ran at 160F-180F, and Now hits 210F?? It's Hard to Say, could even be the Sender and/or Gauge! And even the VOLTAGE to and From, And the GROUNDING of Both!

...As I said 210F is Normal on a Hot Day, Just coming Off the Highway, after a High-Speed Cruize...And Then, Now, Your Stuck in Stop and Go Traffic.
If You are NOT 'Boiling-Over' and Puking Out of the Rad. Cap...You Have No Worries!

In My Opinion!

210F Is What I Read On My Digital Temp Gauge, under the Same Conditions!! Then Five Minutes Later, Cruizing Easy on the 'Side Streets', Running 3 Fans at Full Blast, the Temp comes Down to 187F. I run a 180F RS Thermostat. The Ability to Cool-Down, Proves a Sound Cooling System!

I agree with Marlin, 210 is a good temp as it implies your oil is getting hot enough to burn out the condensation and reduces cylinder wall wear.

quote:

Originally posted by Raiden:
Just recently...about a month ago;

At speed (70mph)... 160 degrees.
In traffic, ... 210 degrees.

Before;
185 degrees...at speed or in traffic
..

As you thought, I also would think stuck OPEN thermostat would be the reason for the cold temperature at speed. However, it does not explain the greater than normal in traffic.

for the greater than normal in traffic, I would expect a fan not coming on.

are you using the original radiator and fan logic. If so is it the dual auto fans or the single/manual

Bleed the air from the system, make sure the belts are tight, replace the radiator cap.

Any radiator hose between the radiator outlet and the coolant pump, if it spans a gap longer than 1-1/2", should have a spring or something inside of it to prevent it from collapsing.

The radiator outlet/pump suction plumbing is significantly too small in diameter. It restricts coolant flow and creates a high vacuum/cavitation condition that can collapse the hoses in that part of the coolant system.

I also invested in the SACC Water pump pulley recently for piece of mind.

Raiden, if it has come suddenly, it's something that worked before that doesn't work anymore. Ideas:
-Leaking hoses, have pressure tested
-waterpump failure
-thermostat stuck
-fans/sensors failed, wires fallen off

Things like another size pulley is not the solution since you didn't need another size pulley before IMO

Also check radiator, the baffle can bypass.
/A

Found one of the two 10 inch pusher fans' wire was loose causing it to operate intermittently. I fixed that and drove 65 miles today, most of that between 95 and 100mph. At speed the temp was at about 160. I got stuck in traffic on the return trip, 826 (Palmetto Expressway in West Miami) was a parking lot for about 20-30 minutes. I never got over 180 degrees. Maybe the thermostat is stuck wide open and with only one pusher fan, I was beginning to get hot. Ambient temperature was 90 degrees according to Weather.com (felt like 99 due to humidity), but it felt a lot hotter in the car on the pavement.

To me 160 at speed and 180 after, sounds perfect to me...

160* is not hot enough for an engine to live a good long life. hard to tell from my monitor but it looks like cylinder bore wear at 160* is possibly double that of running 200*



your cooling system is capable of maintaining 180* in traffic if all your wires are connected, it will maintain any T-stat rating above 180* at all times

FWIW it's easier to tune for a steady operating temp, these old mules don't enjoy the benefit of computer controlled EFI & spark management so basically it's impossible to tune for a widely varying operating temp. also, I've found that my 351C's always run best to the high side of the temp gauge

you think you may have a stuck T-stat, do you know what rating is in it or if it's the correct type with the restrictor plate in place?