Newbie's Question

[jalberg]

Hello! I am new to the sight and to the Mustang world. Last week my Dad gave me a 66 coupe with a 200 c.i. inline six. It has been pretty well restored, but there are a host of minor problems.
The most pressing is overheating. I have read most of the posts on this topic and have started working through a list of things to do. After a flush and some playing with the timing it is better but not solved.
My real question is: Given that it has a 13 lb pressure cap and an overflow set-up, why does it spill fluid out under the cap after I turn it off, rather than having that fluid go into the overflow container? The hole in the neck is not blocked. It is a cheap transparent plastic hose, but I don't think that would prevent fluid from flowing through it.
Any help would be most appreciated.
J.A.

 

[Funky Cricket]

first. hug your dad and take him out for a beer.
then hug him more, then paint his house and clean his garage!


second, buy him more beer.

third, welcome to the site!!! we enjoy pics if you have em, see the user rides section.

fourth.. um.. what were we talking about?.. oh yah. check your cap and over flow system that they are hooked up properly and functioning, also that the tube is not leaking at the cap. good place to start if you haven't checked already.


edit: can't type

 

[Anonymous]

seriously...GAVE you a almost restored mustang... you better get him something good for fathers day

 

[Anonymous]

Run a 160 degree thermostat and see how that works.......

 

[MustangSix]

The engine will "heat soak" after shut down and the radiator will burp out any extra fluid. Modern cars have an overflow tank to contain and recycle that expansion. Older cars just have a hose that expels extra coolant and the top tank will look low when the system is cool.

As far as the overheating, it may be timing. The vacuum advance assembly is prone to fail and can cause the engine to overheat due to retarded timing at high speed. Make sure also that the fan belt is properly tensioned.

The stock cooling system is adequate to handle the engine heat load, but these cars are old and accumulated rust and crud can block the radiator passsages. A quick look in the top tank should reveal if there is any junk in there. If so, have the radiator cleaned by a shop.

Run 50% antifreeze and make sure the thermostat is good.

Finally, do not trust the stock gauge unless you've checked it out. It is subject to voltage fluctuations and may not be reading correctly. An abnormally high (or low) reading could be wrong.

 

[Anonymous]

a lot of over heating questions all of a sudden....summer time is a-comin'

 

[Anonymous]

go to the parts store and have the cap pressure checked. Also make sure it is the proper cap for your radiator. If it is the right cap and the seal is good there is no reason for the water to go anywhere other than the overflow tube. I take it you have actually blown through the overflow tube to check for obstructions.

 

[jalberg]

Wow! That was quick. Thanks for all the advice/ideas.

Yes, my Dad has probably given each of children (there are 6 of them) and several of his grandchildren restored Mustangs. It is a hobby. But at 76 he seems to tire out quicker than he used to. So I am trying to learn how to work on it myself. I bought a 66 200 c.i. engine and have it on a stand, so that I can take it apart and rebuild it and learn how things work.

Thank you again. JA

 

[Anonymous]

Creating a lower pressure under the car will help with the flow of air over the radiator. This can be done by lowering the car or just by installing a chin spoiler on the front valance.

Just FYI... It is a common misconception that a lower temperature t-stat will lower engine temps. It is in fact the other way around. If you are consistantly running hot then you want to go UP in temperature with your t-stat. Yes the engine will run at a higher temp but it will do so consistantly. The T-stat is basically a heat sensitive switch. When it gets hot enough it opens and lets hot coolant past it into the radiator. It shuts off after cooler coolant reaches it. This shuts off the flow of coolant and allows the radiator to cool the hot coolant.

If this thermostatic switch, or t-stat, is not there or open all the time then the coolant will get heat soaked. The coolant just doesn't have enough time in the radiator to cool significantly before reentering the engine.

This is the voice of experience. I was having a chronic overheating problem with another older car and went to investigate it. I found that the previous owner did not have a t-stat installed at all. I put one in and that was the end of the overheating problem.

If you are convinced then go to the next post.... Still not convinced? Read on Very Happy

Think of it this way. My other car with no t-stat was like an engine with a low temp t-stat that has been opened and cannot shut off due to the high temps. The radiator does not have enough time to do it's job and the system goes into thermal runaway.
When I installed a higher temp t-stat, or just installed one Rolling Eyes , the radiator now has time to radiate the heat form the hot coolant and the system is under thermal control.

I am an open minded person and will not take any comments about this post personally. If you feel I have made a gross error then I would be happy to discuss it in the hopes of either learning more or helping to spread my knowledge, limited as it is. Laughing

 

[JackFish]

I sort of agree. I think that if your engine is running at 240*, then it won't matter what thermostat is in there, it will be open, right? The reason we use 160s up north here (AFAIK) is so that when it's freezing we get hot coolant to the heater core to warm up the interior sooner, but that is counter-productive to warming the engine up, especially in sub-zero temperatures.

 

[jalberg]

I don't know if anyone will still be reading this thread, but here is some follow-up. I pulled the radiator, having suspected that it was leaking at the point that the flange connects with the radiator itself. I took to a shop where a kind man tested it and said: "Its terrible when you're right." He then welded it back on and tested it and it is holding fine.
I put in a new thermometer. I am putting a six blade fan. My Dad says to put in a new water pump while I have the radiator out. I am not against this but I am wondering if there is a way to test whether the water pump is OK or not. Or does one just change it to be on the safe side?

 

[LaGrasta]

If the water pumps leaks, it's bad. If not, it's good. Water pumps are really cheap, listen to your Dad and replace it.
I wouldn't worry about the six blade fan so much. If your system is clean, it will cool just fine. Be sure to REALLY flush the system (radiator AND block). It may take more than once to really get it done right. Fill it, drive it for a few hundred and do it again. There always seems to be an endless supply of scale in blocks.
Look into buying "the Book" and learn some tricks on the I6 like drilling a 1/8" hole in your stat and why.
With that said, Welcome to a great bunch of people and cars. I love this place and you will too. I can tell already you're well on your way. It's nice to have you with us.

 

[jalberg]

Do you mean the "book," The Ford Falcon: Six Cylinder? I have it and am reading and rereading.
I do enjoy this forum. Thank you for your help.

 

[mkgcars]

How about the heater core?

I've seen a few overheating posts but no suggestions on checking the heater core.

I know (from back in the day when I drove my '65 in the winter in Boston...<shudder>) that when the heater core is older then the flow can s*ck.

So, would it make sense to remove the heater core and get it boiled out (or replaced if it showed any signs of leaking)?
Or, is the core just not going to play as much part when trying to keep things cool?

I just figure that it's an often neglected piece of hardware in the cooling system, plenty of times radiators get attention or replaced, but not so much the heater core.

All ears on responses.
matt

 

[Anonymous]

The heater core condition shouldn't have a significant effect on engine cooling. The heater core is in parallel to the engine coolant flow, not in series. You could actually splice the heater core supply and return hoses together and the engine wouldn't know the difference.

In really extreme cases, I've heard of people running the heater on hot days to dissipate more heat and help keep their engine from overheating but that's definitely not a long term solution.

 

[CobraSix]

If you are overhauling your cooling system, might as well spend the extra $40 for a water pump and install it. If you don't know the age of the current one, just replace it. Peace of mind. Once you get a good solid cooling system down, you'll be good.

I'm running a completely stock, but overhauled cooling system. The only non-stock part is the 3 row radiator (stock is 2-row). I never have a problem overheating even on 95*F+ days idling in Boston traffic. Now my ass burns from no AC, top down on vinyl seats...but the engine is fine. My point is a stock cooling system in good working order is all you really need on these cars.

Slade