loosing coolant - water pump issues?

[Uboat]

Hi all,

I've been loosing a small amount of coolant for five years, and I have always thought that it is a water pump failure. But there is no sign of coolant on the garage floor, and the coolant fluid shows no sign of oil or petrol.
1. Is it normal for the TC to fill up the coolant regurlarly?
2. Could it be the water pump even if there is no leaks on the outside?

/Ulf

[Tonyw]

Ulf,

Are you sure you are not just pushing the coolant out of the overflow when hot and topping it up when cold? if you had a leak you would see or smell it, try fitting a recovery bottle.

Tonyw

[billwill]

The thin pipe from your filler cap should go down to a bottle in front of the radiator. This you should typically fill about 1/3 full of coolant when you top up your radiator.

Coolant expands and can exert pressure on the inner seal of the rad filler cap, to let it through at the marked PSI rating, it then runs down the pipe to the overflow bottle. On the other hand when pressure in the cooling system falls below atmospheric, a simple low pressure one-way valve opens to let the engine suck the coolant back.

The pipe should be firm an not floppy, as if it is floppy it might suck flat when the engine is cooling, thus preventing the engine from sucking back the overflow coolant. There should be NO leaks around the top of the overflow pipe (Use a small pipe clamp) and the top of the rad cap must seal very well to the top of the radiator.

Avoid opening the rad cap until it has cooled down. If you do so you lose the suction and you will need to transfer the overflow coolant back to the radiator by hand.

~~~~~~~~~

If the water-pump is leaking the leaked coolant should flow out of a tiny hole behind the water-pump pulley. When you stop the car, jam a paper tissue under the pulley to pull out later to see any tell tale blue leaks. Do not forget to remove the tissue before starting the engine.

[promotor]

Could you be loosing the coolant through the heater connections inside the car? Perhaps the hose clips aren't making a perfect circular shape around the heater matrix?

[collins_dan]

Ulf, I had similar symptoms and it has turned out to be a slight leak along the back of the engine, where the head meets the block. It only leaks when driving (and the engine is heated up), so nothing ended up on the garage floor. I only found it due to good detective work based on suggestions from the group. My suggestion is to look around the engine after you've taken it for a drive, with a particular focus only the back. Good Luck, Dan

[ceejay]

During the rebuild of my S2 elan, which is now nearing completion,
the pics below show the set up I have now... Heaps better than
what it used to be like.
Ceejay

[Uboat]

Thanks folks!

I never thought about the overflow bottle or the heater, or the rubber pipe to the bottle.
Nice arrangement ceejay, but I will stick to original...

/Ulf

[billwill]

CeeJay,

I don't see an overflow pipe there? Did you just seal the lot with air in that shiny new bottle so that it acts as a pressurised expansion tank instead of an atmospheric pressure overflow system?

[ceejay]

Dear Bill.

If you have to ask, you probably don't understand, so
lets work through this.

With a cross flow rad; we actually have two header tanks,
one each side of the cross flow core, then we have an
expansion/surge tank situated between the thermo housing
and the top rad inlet, the surge tank is fitted with a high
quality Stant "lever lock" rad filler cap.

Now, note the over flow tube leading from the surge filler
cap fitting, this tube is attached to the barb screwed into
the weld on fitting situated near the bottom of that shiny
new catch tank.

The catch tank is a tad over 1 litre cap, which is enough to
capture the coolant expelled from the system. The tank
will always hold enough coolant to cover the bottom
inlet/outlet hole, so that it acts much like a sealed system.

The shiny catch tank as you called it, does not require
an over flow, but it there is a tiny breather hole drilled
through the screw on alloy cap. (For obvious reasons)

When the engine/cooling system cools down, the coolant
is drawn from the catch/recovery tank back into the cooling
system to replenish what had been expelled. And the process
repeats each time the car is driven.

It's quite simple really.
Ceejay

[billwill]

Ah, no, I did realise what you were doing, about 5 mins after I posted my msg.

I was momentarily distracted by the fact that in standard Elans the coolant overflow pipe goes in at the top of the bottle and I could not see any coolant pipe going into your bottle. Then I realised there's no particular reason (except cheapness) for it to go in at the top. So on a purpose built one it can preferably go in at the bottom.

As you probably know, but for the benefit of those who do not:

Modern systems don't have overflow tanks; the filling is usually done through a cap on an expansion chamber which is only partly filled with coolant, the rest is air and the cap seals it (with an emergency blow out valve in the cap). There are no valves between it and the block & radiator, but it is usually at the highest point in the system. As the coolant expands it compresses the residual air in the expansion chamber and then returns to normal when the coolant cools down. This is a system that doesn't lose coolant if you take the cap off while hot. It also catches any bubbles of air that were, say, at the top of the radiator during initial filling.

For a moment there I thought you had converted your system to an expansion chamber type.

[ceejay]

This cooling system works very well.

PWR Queensland (Aust) supplied the cross flow alloy rad
which also has special mounting tabs for the SPAL
thermo fan which is mounted on the engine side of the
rad.... pulling the air through rather the pushing, which
was recommended by PWR.

And yes, others may argue all day about the pros and
cons of either method (Push or Pull) of mounting the rad
thermo fan.

The 13" SPAL fan moves an extraordinary amount of air.

PWR supply cooling systems to Aussie V8 Super Cars,
NASCAR and F1 teams, so I they know what they are
talking about.

PWR also supplied the surge/expansion tank, and as
stated previously I fabricated the alloy recovery tank.
PWR were very helpful in setting this new cooling
system up

The previous cooling system was the typical old style brass
rad, with ordinary overflow tank, the system was never much
good, while it kept the engine cool, it did struggle under hard
driving conditions in the alpine country.

So during the ongoing rebuild/resto over the past three years
or so, I decided to bite the bullet and instal a top grade cooling
system, I am more than happy with the outcome.

Ceejay

[45bvtc]

Thanks folks!

I never thought about the overflow bottle or the heater, or the rubber pipe to the bottle.
Nice arrangement ceejay, but I will stick to original...

/Ulf

See: elan-f14/cooling-the-elan-europa-t23368.html

[nomad]

Thanks folks!

I never thought about the overflow bottle or the heater, or the rubber pipe to the bottle.
Nice arrangement ceejay, but I will stick to original...

/Ulf

It should be mentioned that if your fitting a recovery system to a car that didn't have one you need to get a recovery cap. Also does the Elan use the shallow or deep filler neck? Cap needs to be the correct one or keeping coolant in the system would be impossible. [Short cap in deep filler neck]
Just sayin!

Kurt.