Humor me with some solutions, because i'm at a loss

[HAWAIISTANG66]

got a 66 w/a 200......overheats going down the road???? I replaced the seizing calipers......helped a little bit, not much....still goes to about 225 230 with the a/c on, then i disconnect the compressor with the electronic fans running and it helps a little, with less load on the engine but going down the road that's when it should cool right.....
well here's what it has
a new 3 core radiator
fan shroud
tried with and w/o a thermostat
2 electric fans
1 5 blade flex fan
new head and head gasket
new hoses
new front calipers
vaccum advance fixed and working
just dont know where else to go with this

I have another radiator that i havent put in, but i feel it'll be pointless you know

 

[rmoe88]

just putting it out there, maybe a bad temp sensor?

 

[ludwig]

Press-on water pump impeller spinning on the shaft? Check and/or replace.

WP pulley too large? Get a smaller one so it goes around faster.

Too lean fuel/air mix at carburetor? This will cause overheating, especially on a long grade. Check with vacuum guage. Turn the mixture screw until the engine starts to sumble then back out to where you get max vaccuum. Then out a quarter turn more.

Lower hose collapsing? Get one with a wire coil inside.

Blockage somewhere? Flush the system from various points.

Move to a colder area. Finnish Stangers don't complain of running too hot. (Akavit for anti-freeze.)

 

[geezer43]

Before you go and spend a lot of money check to see if your radiator cap is good. I have known of similar symptoms to yours and that is all it was. It sounds like everything else you have done is good.

Geezer 43
84 F150 SB XL 4.9 six, T18, 3.55, 232,000 miles one owner.

 

[LEROY POLL]

HEY HAWAII-66


.....FROM WHAT YOU DONE IT SOUNDS LIKE YOU ARE GETTING EXHAUST LEAKING INTO THE COOLENT. BAD HEAD GASKETS OR CRACKED SOME WHERE. BLOCKS ALSO CRACK.

.....THE TORQUING OF HEADS WILL LEAD TO GASKET FAILURE, AND BLOWBY. THIS WILL LEAD TO PRESSURE IN THE SYSTEM. YOU CAN GET RADIATOR FAILURE OR BUBBLING IN THE RADIATOR WHEN IT IS WARMING UP.

.....HAWAII IS NOT THE BEST PLACE TO HAVE COOLING PROBLEMS. THE WEAM MOIST AIR IS PUTTING A STRAIN ON YOUR COOLING. HOW IS YOUR COOLING IN COOLER TIMES?

LIVE IN GRACE

LEROY POLL

 

[Funky Cricket]

also, when it's cool or first started, watch the radiator with the cap off to make sure your getting go movement, I would guess as above,

waterpump not functioning correctly, or cap not releasing pressure

 

[gb500]

check static timing and that advance works with atiming light as you rev it( I see that you have new vaccuum advance).

i had overheating as well - 66 australian falcon with spark control valve advance via diaphram.

only the my vac diaphram was stuffed - so no advance - changed that and still had no advance - turned out the hole in the diaphram had allowed the carb SCV to suck in dirt and blocked the drillings in the carb . cleaned that out and now have advance and no over heating- also reset static to about 12deg

brett
melbourne

 

[x21]

Kind of a silly question for you- but what % mix of coolant/water are you running? I hope you dont think i am insulting your intelligence, because I wouldnt be asking unless my own intelligence was insulted once

 

[Anlushac11]

8)

Has the cylinder head ever been milled?

If so dod you use shorter head bolts or use washers under the bolt heads?

If head was milled enough the bolts will bottom out and you wont get a good seal on the head gaskets and even though you check the torque on the bolts you wont get a good seal.

If head has been milled get hardened washers and place them between ehad and bolt and retorque. See if that fixes problem.


You may have to replace head gasket.

 

[HAWAIISTANG66]

well my screen name may be decieving you, i'm in mississippi right now....so the heat is 10X worse than it ever was in hawaii, but as far as the head, i dont think it's been milled, got it from a donor car...but used the same head bolts from the mustang didnt seem to have a problem, power seems good, so not so sure it's the seal
honestly, i'm not sure the mixture anymore with the antifreeze/water......not even sure it has antifreeze in it.......it hasnt gotten to the point of boiling yet, well i wont let it anyway
but i belive the water pump must be working, i shut the car off and the temp jumps on the aftermarket temp gauge and the stock one crank it the water circulates and it cools again quickly
but i guess winter is coming up soon so i think a drain and flush would be in order, maybe replace the radiator with the other 3 core that i bought new....i've seen it happen with helicopter parts more than one being bad....so might as well cover all my bases

 

[SteveS]

Assuming everything in the cooling system is correct and the ignition system is correct and the carb is not too lean there is always the possibility that the water is moving too fast too.

If the water pump pully is too small there also could be the possibility that the water isn't passing through the radiator slow enough to cool.

All the other suggestions are also quite valid especially the one from Funky Cricket. Flow is everything and it's easy to verify flow.

 

[wallaka]

Assuming everything in the cooling system is correct and the ignition system is correct and the carb is not too lean there is always the possibility that the water is moving too fast too.

If the water pump pully is too small there also could be the possibility that the water isn't passing through the radiator slow enough to cool.

Old wives' tale. Kind of like the one about needing backpressure to create torque.

 

[66 Fastback]

You mention you are not boiling over. Then you may not have an overheating problem if the temp indicators are not accurate. 225 deg F while hot is not a problem with hot weather and AC running.

Have you ever checked the harmonic balancer to verify that the timing mark for TDC actually corresponds to the TDC of the #1 cyl? If that is off then all of your ignition timing will be off and may cause the overheating. My balancer / dampner ring had slipped and although I had it timed correctly according to the TDC mark, it was actually retarded causing it to run hot.
Doug

 

[kukm66]

If and when you go with another rad and flush the system, plug up the outlets for the heater hoses. You may have constriction in the heater tank which will wreak havoc on your system. By doing this, you take another variable out of the problem. If the heater tank was never rebuilt, it is filled with gunk and recylces all of it into the system.

Another area to check is the overflow neck on the rad. The soldered joint can have a pinhole leak and this will cause overheating. As stated, get another cap, replace the hoses after flushing the system, and make sure all clamps are secured very tight near the nipples. Belt must be tightened or it will spin and your water pump will not. Try a water pump from a late model Fairmont or go with a high flow aluminum type avaialbe from Summit.

 

[ludwig]

And while you are pouring stuff in the radiator, pour in some water wetter too. It helps the fluid take up heat better. Ethyline glycol reduces the water's ability to take up heat. And use distilled water.

 

[66 Fastback]

If you flush the system. Make sure you remove the Block drain plugs to get the crud out of the block. You may need to poke a wire up in the drain plug hole to get the crud to start moving out. You might also pull the heater hoses and try to blow out the heater core.
Doug

 

[Stubby]

When we started the 65, it had the original temp sender mounted at the rear of the head and an aftermarket guage mounted in the Tstat housing. The original guage said everything was fine, but the aftermarket guage said 225.

The thermostat had slipped down a little, so I installed a new one with a small bleed hole drilled into the top. It lowered the temp some, but there was still a large difference between measuring at the front or rear of the head.

 

[mikeyo]

If running straight tap water it doesn't take long to plug the tubes in the radiator, especially if the tap water is really hard.
Aside from that what the other guys said, water pump, timing or t-stat.

 

[HAWAIISTANG66]

didnt think of that about the hard water.....
the water comes out of a well pumped up out of back yard.....very hard water

 

[HAWAIISTANG66]

nope, not the radiator.....replaced it with another 3 core....didnt help a bit.....
I got to thinking about the advance timing....
by the way dont know how to do that, advance the timing. I usually just turn it till it runs smoothly....i know that's not exact by any means, but i dont have a timing light anymore, so if i were to advance the timing, which direction would i turn the distributor to get advance timing? clockwise or counter clockwise?