VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1937-1945 Water Pump Question

Hey All,
I took apart my water pump due to flow issues. When I look at the impeller and the way the water pump turns on the car, it seems that it is backwards. My rebuilder assures me that this is correct for this type of car. The arrow indicates which way the it turns when the car is running. Here is the link to the picture: Water Pump

Thanks,
-Davis38

I've never had one apart. It does seem to be backward doesn't it considering it pulls water in through that hose instead of pushing it out. I'll be watching for the explanation. Here's the cutaway of the system.
<CLICK>

Davis38 and Tiny,

The impeller is mounted correctly.

Charlie

Charlie,
Thanks for letting me know! Although now I have to figure out why she's overheating at idle... Back to the drawing board!

Thanks again,
-Davis38

she's overheating at idle . I vote clogged radiator & or block . frank

That's what I was thinking, but I know the block is clear as can be and I just had the radiator cleaned. Carb is adjusted and car is timed. She gets warmer than I would like to see when driving as well. I am quite baffled.

I would still suspect poor radiator flow. I have seen many where the flow was tested and looked OK but the engine overheated. The cure was replacing the radiator.
It is not unusual for the temp. to get up to 180 or higher during idle on these engines.

Davis38,
Take the bottom hose loose at the water pump. Take the upper hose loose and get something to divert the water. Then get an air compressor that will give you about 120 pounds of pressure and an air blower chuck and a rag and stick it in the bottom hose. Use a garden hose to keep a flow of water into the radiator. Pressurize through the bottom hose and blow 'er out real good. Repeat several times. Make sure the fins in the radiator are clear and not bent shut and not filled with bugs and trash. Because you had the radiator boiled this last bit should not be a problem but check it anyway.

You may need the block flushed as well. Blow it out through the petcock on the drivers side of the block. Take out the thermostat first and isolate the block from the radiator.

Check for a cracked block or head by filling the block with water (without the thermostat) to the top of the neck. Trip the fan belt so the water pump is deactivated. Start the engine and look for compression bubbles. There should be no movement of the water until it get hot. You don't need to run it that long. You'll notice bubbles right away. Strong amount of bubbles or a gush will likely indicate a blown head gasket. Otherwise a cracked block or head.

Good luck with it,

You may be able to have your radiator boiled and rodded. Rodding is the best way. Boiling alone doesn't assure that all flues are open. Nor does back flushing as I've suggested above. That process will only assure that enough flues are open to accommodate the pressure of the back-flush.

Let us know how it goes.

Best,
Charlie

Back when I first got the car, the radiator was thrashed so I got a new core (3 rows) instead of the two. The car never reached the 180 mark. While I had the engine out to rebuild, the radiator sat and now I seem to be having problems with it. Would a new 3 row be sufficient in keeping her cool at all times (including idle) or should I got with something a bit more intensive?

THAT sounds familiar. You might find this thread interesting. This was the result after I had my engine rebuilt.

Tiny,
What was the solution to your problem? Did cleaning the radiator solve anything?

Thanks,
-Davis

The radiator shop hot tanked the radiator and fixed a few leaks. I didn't need a re-core. When I got it back I flushed the block with two cans of Prestone system flush & did a complete rinse before putting in fresh antifreeze & water. It resulted in a major improvement in cooling. No more hot running. The only time it gets over 180 (160 deg thermostat) now is when I shut it off. Unless it's a hot day or I just come into town from the highway it stays right at 160. Tanking the radiator and flushing the block fixed my overheating problem.

If the flues are all open and everything else normal then a regular two flue core is sufficient.

In a lot of cases the mere boiling or chemical pour-in stuff merely opens a enough flues to carry the load satisfactorily. Same with back flushing.

An new or properly rodded two-flue radiator (with all flues open) is so capable of reducing the water temperature that a thermostat is needed to get best performance. Oil is best at 180-190 degrees.

Charlie

Hey all,
I am about to lose my mind.... I sent the water pump off had it checked out by the rebuilders; it checked out fine. So I sent the radiator out and had it re-cored, got it back today put it in... low and behold shes still over heating on idle.... WHATS GOING ON HERE?!?! Mind you the radiator is now a 3 row with many more fins than original. The block I know is spotless inside, I personally checked it at the rebuilders. I was wondering if it is at all possible that the Gano coolant filter is causing the problem, at this point if it isn't that I am literally out of possibilites. Thanks for any input guys

You might want to put a box fan in front of the radiator when the car is idling and see if that helps. If it does maybe your fan blades are bent or the fan is backwards?

Before jumping through too many more hoops buy a laser digital thermometer and make sure it's actually overheating. Could be your gauge is lying to you.

From my experiance the gauges never show too hot. When they get older and loose their stuff they read lower.
Cracked head? Bad or incorrect head gasket.?
Does the core feel equally hot all over with engine running (fan-caution).
Can the fan blade be installed back-wards? Incorrect fan?
190 or 200 Deg. is not unusual after a period of idling in hot weather.

Over-heating? How do you know?

a. Does it boil over?
b. Do you fill it up to the brim when cold and then let idle (whatever)? Water expands as it gets warmer. (I know, I know)
c. Are there bubbles coming up?
e. What does the gauge read?
f. Is the fan belt tight enough that is isn't slipping?
h. What is a water filter?
i. Have you put a thermometer in the top tank to see what the temperature is?
j. Have you made the tests for a cracked head/block or blown head gasket that I recommended earlier?
k. Have you been drinking? A lot?

If the radiator is open as you say, it has plenty capacity to keep the engine cool as the thermostat dictates. And if the water pump impeller is spinning at proper speed and the block is open, then there is no reason for overheating. Unless there is:

a. A blown head gasket
b. A cracked block
c. A cracked head
d. A tight, newly rebuilt engine (this can be expected and will slowly go way over time.)

It may seem that it is overheating by viewing a bad gage (See Gene's comment. This is unlikely) or viewing the water come out the overflow when the top tank is fill up over halfway the tank. Just above the flues is enough.

Good luck with finding the reason for your concern,
Charlie

Hey all,
In response:
a. Yes
b. I did the first time and then after that boiled over I left the water level just above the flues and still had a problem.
c. There are bubbles
e. Gauge reads 212
f. Yes
h. The water filter is a series of screens designed to stop any contaminants, I have taken it apart and cleaned it thoroughly
i. I have not
j. I have and no signs of cracked head or blown head gasket
k. Only after this problem started

As far as the fan goes, I don't think its possible to have it backwards. The way I have it on now it sits flush on the water pump pulley, turn it around and there is a 3/8" gap between the pulley and the fan.

Bubbles in the radiator usually is an indication that you have combustion gases entering the cooling system. Blown head gasket or cracked head are a couple possibilities.

You may want to take the thermostat out, leave the top hose off and do the bubble check that I suggested. It will help eliminate the possibility that the bubbles are owing to the thermostat.

If you do so and fill it up to the top of the thermostat housing then the water should not run over or bubble up. Trip the fan belt first, of course. See what happens.

If bubbles or the water rises and then flows over, you may have a cracked head or block. Generally, a lot of bubbles or rush of water right away, indicates a blown head gasket.

By not going about seeking the cause of the overheating by making the proper tests you may have spent money you didn't need to. Its time to find out what is going on. This is not meant as chastisement to you but merely encouragement you to make the tests suggested. And, I hope, not waste any money. Well, any more, at least.

I don't think it's the fan.

Good luck with it.

Best.
Charlie

I understand that its not meant to chastise, luckily this time around when they re-cored the radiator it needed to be done anyway. I will do the tests later tonight and see what comes of them, wouldn't I be seeing milky oil though if my head gasket was blown?

-Davis38

Not unless it is blown out real badly. It is usually just a matter of some compression bypass of from cylinder(s) over to a water jacket hole via unsealed portion of the head gasket.

Charlie

Well before I go crazy and take the head off, I would like to run a compression test and make sure all the bolts are torqued correctly. Does anyone know the cylinder compression and torque specs? I did the test and it seems I am bubbling a bit.
The compression readings (1-6) are: 100, 90, 90, 91, 90, 92
It has just over 2000 miles on the motor and aluminum pistons bored .030"

Thanks all for your help

The compression test readings should be within 10% from low to high.