63 Galaxie with 390 gets really hot at idle

I agree

 

Try playing around with the initial timing, advancing the timing can actually allow the engine to run cooler by lighting the fire earlier. When you are cruising at 40MPH+ your ignition timing will be advanced due to higher rpm's, one thing I would like to know is, if you set your idle higher, will it run cooler longer? Higher rpm = more coolant flow, higher radiator fan speed, and advanced timing.

Though I am finishing up my new SBC, my initial timing on my previous build was best around 10* BTDC. After the engine rebuild, there is no doubt that you may have to tune the engine differently than when it was stock.

btw, if you are running a vac. advance canister on the distributor, that will also have your timing farther advanced while cruising on the highway.

 

The common denominator is hot after rebuild and after the radiator recored.
Reasons for heat...
Friction, bearing tolerances too tight.
Rings, pistons too tight.
Overbore.
Oil starvation... high volume pump, stock pan.
Blocked oil passages, inproper instalation of bearings.
Restricted water flow...
Dobber nests in water jackets.
Shop rag, hose parts, rust scale or casting sand in water jackets. Gasket blocking water.
Cracked block, blown gasket or pin hole in cylinder, Does it steam out the pipes?
Poor recore job, may be far below factory spec.
Honestly I think you have enough air flow. I think the culprit is in the engine or radiator.

 

X2 on advancing the timing, retarded timing heats up the cylinder walls. I fixed my buddies rambler overheating problem noticing that the distributor had slipped and was only putting a couple degrees of advance on the timing. We literally watched it cool down in front of our eyes as I moved it over to 10* advance. Most Ford V8's I've worked on like around 12 to 14 degree advance.

 

I went out and advanced the timing a bit this morning. It seems to have helped it out slightly. It now stabilizes around 212-215 degrees while idling instead of continuously climbing past 230. But I'm wondering if it's because the engine is running at higher rpms while idling now causing the fan to turn faster.

 

Adjust the idle screw down to get it to idle where it should and see if it heats up.

Either way, something is screwy here. This is a basically factory set-up, with a mechanical fan and shroud. There is no good reason this engine should run hot. I'm starting to think it's a more serious issue, like a bad radiator or head gasket.

 

I think getting a look a the head gaskets would be my next step, and taking some pics, maybe someone familiar with your heads will see a glaring problem,,you seem to have covered all the bases.
Good Luck

 

Idle it down and find out. If it stays at 212-215 idling that is fine. My 460 typically rests at 220 when idling in the summer. Never had a boil over. With a 13lb cap it shouldn't boil over until its past 246-250ish. Also, what is your anti-freeze to water mix? I use as little antifreeze as possible, just enough to provide freeze protection for my areas lowest possible temp (about 28 on a cold year) because antifreeze is not as good a heat conductor as water. In fact I didn't even need antifreeze this year, I've just been using water wetter and keeping an eye on the forecast, lol.

 

BootleggerMatt is correct; The math to figure it out is each lb. of cooling system pressure will raise the boil point of a 50/50 coolant mix by 3 degrees. 3 x 13 = 39. Add 39 to the 212 degrees boil point , and it gives a pressurized boil point of 251 degrees. Your temps are well within that range,.....

4TTRUK

 

i'm thinking just maybe you do have wrong head gaskets and its blocking the water passages??????,it should not run that hot

 

The quickest way to check for an air flow problem is to put an electric fan in front of the vehicle to see if it cools better.

 

x2 for timing. My FE would heat up at idle real fast. Adding a few degrees of initial timing did the trick, engine found a few more ponies too

 

Are you sure the head gaskets were put on correctly? They'll go on more than one way and run hot when put on incorrectly..

 

I noticed it has been a few days, any progress on the issue?

215*F is not TOO bad depending on the cast thickness of the heads, but it would be nice to get it down lower.

If your still working at it, it would also be a good idea to double check and make sure there are no air bubbles coming out of the cooling system while the engine gets hot, this would be a sign of a head gasket issue.

An old engine that I got from craigslist was assembled using an air wrench instead of a torque wrench, and when my heads got up to temp (200*F) they warped permanently, and I had cylinder gases trading across two pistons. This caused me to have a weak idle, loss of power, and the engine would heat up quick past 230*F if I was not watching it.

It would be a good easy job to pull the valve covers off and double check the torque on all the head bolts. If everything seems to be checking out ok, and your not experiencing big power loss, I would not worry too much, 215* is not bad. Rebuilt engines tend to run cooler after they break in fully, just run good oil that contains zddp, and maybe get an aluminum radiator (that always helps). (I run castrol edge 5-50 classic car formula 1800ppm zinc, I contacted them for that number. There's a big debate on breaking in an engine with synthetic oil too, check up on that.)

Good Luck.

 

I'm curious what you will find. my 460 does this as well. I messed with the timing and also checked my advance curve. the air coming through the radiator is so hot it causes first degree burns. I had red arms for a day just from messing with the distributor while the engine was running. I tried initial timing from 5-12 degrees.

I don't think it has a head gasket problem, I'm not losing coolant.

When I shut down the engine and slowly remove the radiator cap, the coolant will start boiling. A gauge could fool you but boiling water cannot.

In stop-n-go traffic I have to keep shutting it down. It's fine otherwise. It had 82k miles when installed and I've put on 130k miles since then. I've replaced the radiator and fan clutch to no avail. When I disconnect the top radiator hose and hang a running garden hose in the radiator it stays at 180 nicely.
Sounds like the same problem. why??

 

I would try to borrow a larger carb. It just plain may be too lean at idle. Had some what of the same problem on a 440 Dodge I built for a buddy of mine.

 

These things are pretty hard to analyze over the net, but an easy thing to check is to pull the water pump. Take the plate off the back and be sure the impeller looks o.k. I have heard of instances where the impeller was actually not hooked up to the shaft!! This is easy to check and would rule out one potential problem! Good luck!! P. S., does the engine run alright, plenty of power??

 

try evans waterless coolant???
http://www.evanscooling.com/

 

Update:

A buddy of mine helped me advance the timing to 12 degrees and tune my carb this morning. The car now stays around 185 when cruising, and doesn't get any hotter than about 210 when idling now. And that was when I just let the car sit and idle in my driveway for about 20 minutes straight. This is drastically better than it was. I have a Holley 600 carb. We set the adjustment screws on both sides all the way to the right, then backed off of each side 1 full turn. Before we did this, the adjustment screw on the left side was backed out 3 1/2 turns. I think it was way too rich. Everything seems to be much better now. Way more responsive and powerful.