ok. i have just upgraded both my engine and my radiator. went to all aluminum radiator and have upgraded engine to 350 pushing out about 450hp. well, they had to use my old water pump on engine as high output pump that was on there would have pushed fan into radiator. soooo, i was out cruising today and it is about 50 here and when in stop and go traffic, my temp goes up to 210. i don't like it that hot. i have an electric fan on front of radiator that can cure this, but i was wondering if anyone else has other ideas. oh, original fan and clutch on engine as well. i am thinking it is water pump, but when i get air on radiator, temp comes right down. any thoughts, or just live with it?

 

Make sure your temp is really 210,and it isn't a phony reading.

the motor HP is not an issue, as you don't use that much HP driving around,a nd not more thana few HP sitting at a light.

Doug

 

Especially if you used a new temp sender.

 

yes, it was a new temp sender. had to, no way to get that old sucker out of old engine. it was mated hard so we got a new one. best way to measure temp? off of radiator or off block near sender?? i was thinking of getting a laser temp gauge anyway.... just where to shoot it.

 

if it's a replacement sender than better chance than not it's just reading wrong. Replacements are notoriously wrong on their readings.

When using an IR temp gun ytou should read off the radiator hose near the t-stat housing, not on a metal surface.

 

If you see the temp going down when cruising, then it means there is not enough airflow (or waterflow) at low speeds. Do you have a stock pulley (not underdrive) on the balancer? Just went thru this on my car...

Run vacuum advance on distributor...really helps

Or low coolant level??

If the temp is at the thermostat rating at cruise then I would asume the gauge/sender is OK.

 

I had a similar question last week, my gauge temp was a consistant 210. Changed state and sender, still 210. IR gun today found the hottest temp on upper radiator hose was 168.

 

Try an experiment. When the engine is hot, stop and shut it down. Pop the hood and try to rotate the fan by hand (engine off).

When hot, the fan clutch should be engaged making it difficult to rotate the fan (coupling the fan to the pulley with considerable resistance). If you can spin the fan easily, when the clutch and the radiator airflow is hot, the fan clutch needs replacement.

This is the mission of a good fan clutch: high torque coupling when hot and low torque freewheeling when cold (cooling airflow only when you need it).

HTH?

.

 

I had the same problem with my 350ci in my '61. The radiator shroud had a 3" gap that caused air by-passing. After closing the shroud the temp droped to 180 .

 

Richard, how did you close the gap? Did you replace the shroud or is there a gap filler kit? I have a stock 62 with a large gap between the shroud and the radiator, and it heats up when not moving. Prefer not to change the shroud.

 

The gaps on the sides of the rad can be closed off two ways.

I believe in 1962, the factory offered rubber strips that sealed the front of the rad support to the rad. I think I have seen these as repop items.

I just went to the hard ware store and bought 2" OD black polethylene split closed cell foam pipe insulation,and dropped one piece down on each side of the radiator in between the rad and the rad support. It seales the sides of the radiator off fine, and I didn't have to remove the hood or grill to do this.

I haven't done this yet, but would suggest you also get some 1" (or maybe 3/4") black plastic pipe to put inside the insulation to keep it rigid. One side stays in place well, but the other side wants to try and migrate into the fan area during high speed runs.

Doug

 

I've never seen a cooling problem that was caused by a water pump; do you have the correct shroud and is the fan correctly positioned half-in and half-out of the rear edge of the shroud? Step #1 is to shoot the upper radiator hose with an I.R. gun to verify that you really have a problem.

 

I had problems with temp as well. I bought a mechanical meter with probe. I took out the sending unit, installed probe and sent tube though fire wall, mounted gauge under dash just to verify temp as I was driving. Sure enough temp was good and sending unit was wrong. This a nice way to monitor temp in norm driving, warm out up hills idling. When I knew temp was OK, I took out temp meter.

 

Even if your temp gets up to 210, that is not that bad and will not hurt anything. 230 to 240 better start looking for some water cause you are about to lose some coolant. Remember, more antifreeze is not better, don't mix more than the maximum of 50% antifreeze to 50 distilled water. Add water wetter also. If you live in areas where it doesn't freeze, run less antifreeze, maybe 25 to 40%. You will be amazed your motor will actually run cooler. Make sure there are no air pockets and never use a corrugated radiator hose. You may also want to get a high flow thermostat for about $10.00.

 

Not that I use one, but out of courisity whats wrong with the use of a corrugated rad hose. Does it slow down the flow of coolant?

 

Yes and no. It does restrict some flow and back pressure but the problem is it causes the water to mix causing air bubbles. Air is not good and may cause pockets of air which will form. This may cause overheating and you will need to burp the cooling system to try and get it out. It usually isn't the main problem but can contribute. It would be the last thing I would do if I were working on cooling issues.

 

Make sure you are getting full vacuum at all times for your vacuum
advance on your distributor if you are using a vacuum advance type
Dist. I had a Holley carb. on the engine when I first started it up ,
[new one] I couldnt keep it adjusted right, I tried and tried, gave up,
bought a Edelbrock carb. [ havent adjusted since I first put it on]
I read the whole phamplet that came with the carb. I did'nt under-
stand what ported vacuum ment and full vacuum is. So I ran it with
the distributor hooked to the ported side but I promised myself that
I would research this and not leave it as is , I went to a lot of car
shows in the New Jersey and Penn. area and found a lot of Edel-
brock carbs. in a lot of shows . Macungie,Pa. Rod Show had about
40 of the Edelbrocks in various cars . Guess what about 50% of
the cars had the Distributor hooked to the ported side. The ported
side is for EGR valves only. [ I found out that the dist. needed full
vac. from John Hinckley on this forum ]. The engine will start to
heat up at idle [in traffic] without full vac. I sent a E-Mail to Edel-
brock to explain better ,the dist. needs, and I never got a reply. I
Just know those guys with the Street Rods had a overheating prob-
lem in traffic. But how do you tell them? They are all probally are
all shade tree mechanics like me. The Phamplet from Edelbrock
has to be rewritten to make it so these guys hook up the Dist. vac.
advance correctly. Just my 2 cents.

 

Pull the electric fan out of the way, it is probably blocking flow, unless it is running.

Check IR gun temps on the thermostat housing, water pump, front of heads. The IR gun will record the highest temp encountered.

210 is in the normal operating range.


I fly a King Air 200 with PW - PT6-42. The Max engine temp on the ITT (hot section) is 800*C. In the summer it is there on take-off, in the winter, it can be in the 650 range!. There needs to be a range of operation. Keeping the temp at 180 for every condition is an unrealistic goal.

My vette runs at 180 down the highway, and in August, 99*F 99% Humidity with 4:11's, at 90 MPH = 4500 RPM, it may get to 195-200. If I pull off the highway and idle the car, it will go to 210-215, then slowly come back to 180.

Mark

 

i have the original distributor since i want to keep tach. i dont have vacuum advance. or am i way off here? should i have the car a little retarded or advance to help cooling? i need to keep electric fan cause i go to dreamcruise every year. need it there. 4 hours sitting in traffic is alot to ask without it. i apologize if i am way off on distributor vacuum issue, but i think it is mech advance not vacuum on tach drive dist....

 

yep, you should be running a vacuum advance on there and it should be hooked up to a full vacuun port. If your carb doesn't have a port for full vacuum advance than you can get a fitting to pull it straight off the intake manifold.
Running the timing retarded usually causes temp to run hotter and I think if you run it too advanced it can do the same thing.

JohnZ has a great tech article that explained about the vacuum advance.
I have it posted up in the tech article section of my website if you wish to read it.
here is the link to my tech articles section: Tech articles
The file name of John's paper is: Timing101article.pdf
if you click on it it will open up or of you right-click on the file it will download to your own computer.