Waterpump Failure - Failure Identification

[James R]

Hi All Dolly fanatics..

As a new member to the forum, but not to owning a dolly, I am after some assistance and advice before embarking on a waterpump change in my 74 Sprint, which I will add here is not on the road currently. Symptoms were initially huge pressure in the system where water did not appear to be circulating, which resulted in the Torquatrol appearing to fail. this has been removed along with the fan obviously. I left the car for some months and on return spent time trying to diagnose the problem. When running the car, it warms up OK, stat opens (tested it out of the car) and top and bottom main rad hoses get hot. However pipe from pump to heater via the 'H' piece only gets hot at the pump end and it is cold at the 'H' point. there is no blockage in this hose, but when the hose is removed and car is running, water is pumping out of the pump area, but I am assuming that it is not sufficient to push it round the heater. I would appreciate any views before I start the job of pump removal just in case it isn't the pump and anyone has any other ideas of how I can eliminate other factors..

any views greatly appreciated. Thank you.

[Jon Tilson]

Quite a few things can go wrong with these pumps but most are accompanied by nasty noises or water leaks.

If you dont have either but you say you have checked the thermostat and water comes out of the heater hose showing the pump is doing something
then the next question to ask is....

Did the thermostat have the lower foot? This seals off the bypass tube when the thermostat opens. If your car has in the past had the wrong type of stat
with no foot fitted that may be what is causing your problem.

The deal with these is that you do/check everything else before stripping the pump....

If you need to there is a guide, but lets not get ahead of ourselves...

Jonners

[80Sprint]

Torquatral unit is not related to the pump/water circulation. Did the engine over heat or dump water out of the expansion bottle or did you just have an issue with water going to that pipe. If it was just to the pipe then the heater may have an airlock. You need to fill these with the heater on hot.

[James R]

Hi Jonners

Thanks for reply, really appreciated.

OK as for stat I will need to check about the foot you mention, but I removed the stat and then ran the car without it. same thing happened, top rad hoses hot, rubber pipe from pump hot but heater hoses at the 'H' section cool. and so again I assume that the pump is doing something. prior to this I had no water leaks but there was a noise from what I took t be the bearings of the torquatrol. not all the time just infrequently.

and can I ask where the guide you refer to is please?

Thank you again

[James R]

Hi Mike,

Again thank you for your response, it is really appreciated. car didn't overheat as such but guage was increasing so didn't push it. went past its normal middle position, so turned the car off. pressure in system was huge with rad hoses rock solid..

if there is an airlock in the heater, which to mention I had on all the time I was tinkering, how is this achieved? do you need to bleed it via the thermostat housing as normal or is there another way. with the warm water not seeming to circulate into the heater matrix will there be sufficient pressure to push any heater held air out via the thermostat?

Thank you!

[Toledo Man]

Are there any leaks? The bypass tube between the inlet manifold and water pump is prone to leaking which can happen if the inlet manifold has been removed and refitted. I agree with Jonners. You should fit the 82 deg thermostat with the jiggle pin. What is the coolant like? You should be using a glycol based coolant (such as Bluecol) with about 40% antifreeze and it should be renewed every 2-3 years. Check your rad to see if it is blocked.

THIS is the guide (AKA The Dolly wiki). You can also download the parts catalogues and factory workshop manuals HERE. Hope they help.

[sprint95m]

pressure in system was huge with rad hoses rock solid..

As well as doing the checks already suggested, I would do a compression test first.



The bottom hose should be cooler than the top hose.

You should be able to purge any air from the heater by removing the upper hose and making sure only coolant is coming out,
but I favour a more thorough approach....
I would back flush the heater (you can use a garden hose and don't need to remove the heater) and
furthermore would remove the radiator so it can be turned upside down and back flushed.



Ian.

[xvivalve]

As Mike has said, the viscous coupling is not connected to the water pump.

You fear the viscous has failed, so have removed it and the fan, and now wonder why the car is running hot?

There is no reason to suspect your pump seal has failed unless you are losing coolant out of the telltale slot beneath the cover. It may have stripped its gears, or the impellar slipping on the shaft, but the symptoms then would be water escaping from the expansion tank as very little would be circulating - the fact top and bottom hoses are both warm hints at this.

Excess pressure in the cooling system is often a sign of head gasket failure. Does the coolant level drop at all? Get the coolant tested for exhaust gas content.

The H acts as a bypass for the coolant when the heater is off. If the pipes are only getting warm up to the H and not beyond it infers the heater is off; a common fault with these is a sticking valve. You can normally tell if the valve is stuck as the on off lever springs back when you try to turn the heater on, but this is easily strained and the linkeage bends to fool you into thinking the heater is on when it is off.

I suspect you may have more than one problem.

Where are you?

[Jon Tilson]

Dave please stop posting tosh about needing 40%.
On the bluecol packaging it states that adequate frost protection for typical UK climes is 25%.
At 40% the thermal capacity of the cooling system is significantly reduced, so it will run hotter and may go critical in a traffic
jam at 30C.

Jonners

[Jon Tilson]

Water pump guide is on the dolly wiki site.
Please dont use until you are certain you need to... .

Here...

https://dollywiki.co.uk/wiki/Water_Pump_Overhaul

Jonners

[James R]

Thanks guys for all of the advice. I will revisit and try the easy options first. already backed flushed and checked rad, looks fine, so will do the heater as well and also check again for leaks in the system. will also check the heater sticking mentioned by xvivalve. fingers crossed that it isn't the head gasket or anything more sinister.

I am in Berkshire BTW and also the car isn't on the road, if I haven't mentioned that before. not sure it makes any difference, although with this I didn't see the fan as critical with the running at this stage. knowing this just helps with the picture.

will let you know how I get on, and thanks all thus far. really appreciated..

James

[Jon Tilson]

I visited a yellow Sprint in Berks a while ago and tuned it for the owner.

Was that you?

If so happy to pop in again....

Jon

[James R]

Hi jonners,

No that wasn't me I am afraid.

might just take you up on that offer at some point, particularly if I am not progressing with this little issue!

[Jon Tilson]

Have sent you a PM...

Jon

[James R]

Hi All,

Just a quick update, which is positive..

Got the water circulating correctly at the weekend through the heater, but not sure exactly what I did that changed this situation. I removed stat, and the heater hot/cold slider wouldn't stay in the cold position , so I decided to try it in the cold position and so wedged it. Result all good with pipes getting nice and warm and car was running well. After a while (15/20 mins) the guage started to slowly creep up to the middle, but as one of the other guys said this is not surprising with the fan not installed. So I think i can now at the moment anyway assume the water-pump is working..!

All i need to address now is the torquatrol issue. It wasn't functioning after it made a nice imprint in the radiator (hence its removal in the first place) but this is one subject that I really don't know much about. so going to have to do some digging around about can bearings be replaced, can it be overhauled, or if it doesn't work is it to be disposed off and replaced with an after market fan set up?

Thanks again to all for your help with this issue. good to know that help is available.