Standard Ford 302W water pumps

All

Are the standard ford water pumps up to the task of circulating coolant in a GT40? I am using the standard reverse direction (serpentine) pump which came with the 302W engine. As the engine warms up it starts to make a noise like a kettle, which is very worrying. This noise starts before the thermostat opens. As soon as I increase the revs the noise goes away. The engine has been bled many times now and I do not think there is too much air in the system but this noise persists. I have just tried it with the thermostat removed and it has improved a little but not much.

The only conclusion I can reach is the coolant flow rate is so low that the water is boiling in the heads at idle. The overall coolant temperature is in fact OK. The temp gauge and the ECU temp sensor both say the temperatures are within limits.

Should I be looking at another pump. If so any recomendations?

Regards

John

 

[flatchat(Chris)]

What kit? Was the motor overhauled? if so, did the head gaskets go on the right way? otherwise probably a crook bearing in idlers,altenator, water pump or just a plain noisy belt.

DRB#17
yellow/red
320rwhp and slicks

 

The motor is new but was stripped for balancing (by an engine shop). I'm not sure if the heads were removed. If the head gaskets are wrong is there a way I can tell? If the water passages were completely blocked off, I would not have any water at all in the heads (I know there is at least some water in them). Would that be the result if the head gaskets were incorrectly fitted.

The noise is not mechanical. It continues for a couple of seconds after the engine stops.

Regards

John

 

[flatchat(Chris)]

Should be able to see a square corner of the gasket at the front outside of the heads ( water pump end)
May be with the aid of a digital laser temperature sensor might show where the hot spots are--if any?
There are large holes at the rear end of the gasket. The water flows from the front of the block to the rear and up through these holes from the rear of the heads to the front and out via. the thermostat
What about an air or vacuum noise?? A leak down of the brake booster?? good luck C.H

 

[Ian Clark]

John, GT40s are notoriously hard to get all the air out of the cooling system. Unless you rad is undersize, I would suspect air trapped in the top of the engine. Does you intake manifold have access to the coolant passage on the engine side of the thermostat? If it does, check for coolant there when the car is cool. I'll bet there's no coolant to see in the hole. Air accumulates there and the thermostat never gets to see the hot coolant in the heads. So it doesn't open and you get that kettle sound. Filling the system to be sure the top of the engine is full is another story. Check it out, I'll bet that's your problem.

Oh yeah, if you have a heater in the car make sure it's on while your filling/bleeding the system. A little air trapped in there will come back to haunt you (been there, bought the t-shirt).

While I'm on it, make sure your header tank is higher than the intake manifold and you bleed the rad. The pump is not your problem IMHO.

Cheers

 

[Howard Jones]

I think you have air in the motor. This is VERY common.

Warm up the car to above the point that the thermostat should be open by leaving fans off.

Turn on heater water flow to full hot, or disconnect the heater lines at the motor and plug them prior to trying to bleed system.

Turn off motor.

Jack up the front of the car to as high as you can with the rear wheels on the ground.

Open bleed valves on both sides of radiator and allow air to escape. If you don't have these bleed valves you need them!

If this doesn't work before you do the following make sure there is no pressure in the system.

As a further step if you can't get all the air out, attach a long hose, with a fitting that will seal correctly, to the port that the water temp sender goes into, remove it first and fill engine with coolent from this port. The hose must be long enough that when the front wheels are up in the air the end of the hose is higher than the highest point in the car that contains coolent. Put a funnel into the end of the hose and continue to fill the system with the bleed valves open on the top of the radiator until coolent comes out both bleeds. This will fill the engine first and then force the remaining air forward in the coolent system and out of the system thru the bleed ports in the radiator.

You will want to mix up at least 4 gals of 50/50 mix of antifreeze and distilled water. With the flow of coolent onto the floor you might want to mix up 5 gals to begin with.

Lower car to flat again and remove hose, put temp sender back and , get it hot again, turn off, jack up, bleed radiator again etc. Continue this process until no air comes out of the bleeds at the radiator. You will do this more than once as the small air bubbbles tend to remain seperated in the system. By running the coolent around the system between bleeds the air bubbles will come together and be easier to remove. Also giving the system a little time to condence the air bubbles after turning off the motor seems to help so also. Aprox 5-10 min is a long enough time to condence the air but short enough so that the systems does not cool down to much.

Isn't this fun! By the way I didn't put a heater in my car so as to not have more air traping problems. If it doesn't get real cold where you live you might want to do the same.

 

Thanks for the info guys

I will try out these ideas over the weekend. In my case the heater pipes on the water pump are blocked off. I do have a heater, but it comes off the water pipes as they go down the center of the car on the floor. The heater has a static bleed on it and has been bled. It almost certainly has some air in it, but that air should stay where it is at least and not end up in the motor.

I will let you know how I get on.


Thanks

John

 

I'm not there yet, but I think (maybe hope) its getting better. I've managed to get coolant everywhere during the process.

John

 

[David Tickle]

John
I'm no expert on 302's, but my GT40 has given no problems with entrapped air, or overheating. Prior to building the car, I read of many difficulties in this area and saw diagrams of water circuits etc.

The trouble with air locks is that you can't always rely on gravity to eliminate them so I followed the book method of piping the water pump. This is based on the principle that there must always be a small flow of water around the pump even when the thermostat is closed. (In the old days of UK cars, there was a small hole in the thermostat to achieve this). Now that the thermostat has no bleed hole, this small flow is achieved by small bore piping to circulate water through the pump and block. The heater pipes do the same job, but the heater valve may be closed. The water is also circulated through the head tank.

Maybe this would stop water overheating in the heads. The other thing to consider is that standard motors in standard cars don't boil water in the heads, so why should yours?

Regarding trapped air, there are three high points in the system. One is at the top of the radiator. The pipes travel at lower level to the block which is the second high point (at the header tank). The third is the heater. I have one bleed to atmosphere at the top of the radiator and when filling, this is open. Once filled, I can start the engine, run till the thermostat opens, open the heater valve to circulate through the heater and check the radiator bleed to remove any air that has come through the pipes. After that, stop the engine, allow to cool and top up. Periodically, over the weeks, the radiator bleed valve was opened to check, but nothing other than water came out. (At the risk of stating the obvious, the header tank cap should be removed before this as partial vacuum in a cooled system will cause air to enter the bleed). Any air in the engine block is circulated out to the header tank.

Once filled like this, how can air get in? I have run the car for 3 years now (not many miles) with no overheating or boiling.

Hope this is some help

Dave Tickle

 

[Howard Jones]

I am sure that, on my GTD at least, the rear of the engine block, flywheel end , will trap air when the system is first filled. Thus the reason for lifting the front of the car when bleeding. When I do this the engine can be heard to "burp" as the air at the rear of the block works its way forward.

I agree with you on the main point, once all the air has been removed none should return unless there is a leak. This leak could be above the water level of the system such as the pressure fill cap,weak or very light spring pressure, or a fitting being very slightly loose or misalined. The air would then be drawn back into the system as the coolent cools down after the engine is shut off. This would explain how the system never seams to get all the air out.

 

[David Tickle]

Hi Howard
OK, I am working in Shanghai at the moment, so cannot do a visual check, but my car has a pipe (one of the small bore minimum flow ones I mentioned) connected to a threaded port at the rear of the engine. This port is in the water side of the inlet manifold on the left hand side of the block. Thus air at the back of the block/manifold can be circulated out to the header tank.
Regarding your second point, as GT40's have a largish radiator and long piping from front to back, the volume of water seems to have enough expansion to overfill my header (expansion) tank. So I do loose water via the overflow sometimes if the pressure cap lifts. This lift isn't due to temperature as the highest I get is about 103degC in stationary traffic. I must find out what the coefficient of expansion of water is, estimate the system capacity and do a calc.

Regards
Dave Tickle

 

Thanks for your thoughts guys. The discussion has been really useful.

I think I've got it now but I had to scare myself silly by trying to find out how far I was game to jack the front of the car up. At the end I had a chain connecting the jack to the rear of the car so the jack would not slip out from under it. That's the trouble with flat bottom cars, I guess. I drilled a couple of extra holes in the thermostat as well.

Anyway, it works and I am extremely grateful.

Thanks All

John

 

[Ross Nicol]

I've run my car on some really hot days now and over heating is no problem at all.The secret as has been pointed out is to get rid of the air at the rear of the heads. I ran
a pipe at the rear of the inlet manifold from side to side and teed a pipe off this to the thermostat housing. When I fill the cooling system all I do is crack the fitting at the rear of manifold until all air is gone and tighten it back up.I sometimes have trouble getting the car hot enough.
Regards Ross

 

[Robert Logan]

John,

The system that Ross Nicol discussed in the last thread is our standard system and this was designed for our cars to stop the build up of steam at the rear of the heads.

The water pump / cam chain housing could be your problem. Please contact me tommorow with the Ford numbers of both and I will tell you if they are correct. The housing could be incorrect as they are ported for clockwise and counter clockwise rotational water pumps.

Talk to you tommorow.

Best wishes,

Robert