I think my radiator is too big.....?

[soe8m]

Cardboard thermostat.

Check your ewp plumbing. Not a bucket under a leaky tap repair.

Jeroen

[tony g]

EWP is plumbed according to instructions so I cant see any probs there. Ian I suspect has the same set up. Do you suggest a different set up from EWP instructions?

Tony

[soe8m]

Yes. But you have to ask yourself an important question first. Do I want a working heater? Yes or no are two different setups.

Jeroen

[sprint95m]

Ian / Tony

Have either of you done a recent run with a radiator blind covering half or more of the radiator surface area?

I'm still concerned you might do something that compromises the benefits on a hot day in summer - which obviously is some way off!

Geoff

I have tried that Geoff. No difference.

EWP is plumbed according to instructions so I cant see any probs there. Ian I suspect has the same set up. Do you suggest a different set up from EWP instructions?
Tony

Following what you said yesterday about reinstating the thermostat I have thought of an alternative:
For the bypass, use a hose tail to Tee a hose into the bottom hose before the EWP.
The sender (for the controller) would need to be relocated (to beside the temp gauge sender).


In 2007 two articles appeared in Dolly Mixture where the writer had retained the thermostat,
I have studied his set up and don't understand how it could work (because he didn't reroute the by-pass system
or reposition the sender from the top hose).
He reported a marked temp rise on moderate climbs.....



In a much earlier article Tony McKillop (Mig Welder) wrote about his EWP installation on a Sprint.
Other than needing a booster pump for the heater he didn't seem to have any problems.




I haven't had a reply from Davis,Craig but I suspect that the problem we have is not uncommon,
I say that because the controller (8000) introduced last year controls the system in a different way as the engine warms up.
As soon as I hear from DC I will report here.




Ian.

[sprint95m]

EWP is plumbed according to instructions so I cant see any probs there. Ian I suspect has the same set up. Do you suggest a different set up from EWP instructions?
Tony

Following what you said yesterday about reinstating the thermostat I have thought of an alternative:
For the bypass, use a hose tail to Tee a hose into the bottom hose before the EWP.
The sender (for the controller) would need to be relocated (to beside the temp gauge sender).

Doing some more research and came upon an interesting thread on a Saab 99 forum in Australia.....
Davies, Craig EWPs don't work with the thermostat in place because there is insufficient flow (through the by-pass)
causing them to overheat and fail.
(There are posts from a washing machine engineer (seriously) explaining this.
So my suggestion above won't work.

There is, however, an EWP made in USA which you can use with a thermostat in place....
EMP Stewart Electric Water Pump E389A-BK14
To use this you would need to re-plumb the by-pass as I indicated above.
No need for a controller either...
Even with the import duty, it is pretty much the same price as a DC EWP & Controller



Ian.

[tony g]

But if the temp increases and the stat opens wouldnt that relieve the lack of flow? If a stat on a normal system stuck shut we would have an overheat too. I think Im still tempted to try a stat (82deg) and monitor what goes on OR add a further restriction to the gutted stat. I was thinking more about the flow path through an open stat and although I havent measured it, it is very small compared to hose diameters.
Strange that we are both doing this now yet plenty of people have done EWP conversions and the internet is only full of success and not fails?

Tony , (Migwielder) are you reading?, Care to add your experience?

Cheers

Tony

[tony g]

From FAQ on CD site:

If I buy an EWP without a Digital Controller, should i remove thermostat?

This depends on the vehicle and what the vehicle is used for? Generally for short circuit race/drag applications and engines used under extreme conditions we recommend removing the thermostat to provide the greatest cooling capacity. It is always recommended to use the controller for other applications, however if you have decided not to then we recommend to drill a small 5mm hole in the thermostat to allow some flow and release of back pressure when the thermostat is closed. You may find in these circumstances that the engine temperature is not managed effectively and also the pumps life will be reduced if the controller is not used.

This implies keeping the stat can work with a relief hole drilled, when not using a controller. I think even using the controller will use the ewp less and can still do enough once the stat opens. Im also thinking the temp sensor supplied with ewp may work in the bottom hose so if the water coming out of the rad is not cool enough then the pump/fan can do its work.

Tony

[sprint95m]

Had a reply from Davies, Craig....



Hello Ian,

Thank you for your email relating to the engine temperatures of your Triumph Dolomite.
In some climatic conditions, the engine temperature may not reach the set/targeted threshold during normal operating conditions, especially among some smaller engines.
We suggest in your circumstances to replace the thermostat in order for you to retain the required operating temperature in your engine. You will need to drill 2 x 5mm holes in the thermostat plate if you replace it. The EWP and EWP/Fan Digital Controller combo will continue to manage your engine’s cooling function as designed.

Please come back to me if you have any further questions.


Kind Regards,
John F Benson
JOHN F BENSON
Sales & Marketing Manager




I am going to try this as a temporary measure,
even though I know it will place extra strain on the pump.



Ian.

[sprint95m]

Do I want a working heater? Yes or no are two different setups.
Jeroen

I don't know what you mean Jeroen.

The heater works (as well as it does with an 82 degree thermostat that is ),
it is plumbed in with the feed coming from the cylinder head
and the return going to (before) the water pump.



Ian.

[tony g]

Ok its along the lines we were thinking at least. I noticed they've gone from one 5mm hole to two
I guess when the engine is warming up the heater is open offering some movement too and when fully up to temp stat is open and enough flow to take away the load from the pump. I was thinking of a 82 deg stat and set target to 90 deg. What are you going to try Ian? (I wont get chance until the weekend now)

Cheers

Tony

[MIG Wielder]

Hi All, Sorry about the delay in replying. Yes I have the Davis-Craig EWP fitted to CWL (a Sprint) & it is currently my restoration project.
The reason I fitted it was because a brand new mechanical water pump stripped its drive cog plus the cog on the jack shaft, and it was cheaper to fit the EWP, than fit a new mechanical pump & jackshaft. It was also technically interesting. Yes, I read the instructions but I couldn't see a reason for removing the thermostat so I left mine in. I can see the reason possibly now with the comment on back-pressure. I made my own water-pump cage bung from 2 brass discs brazed in to the original brass housing with new sealing rings. Now CWL was my daily driver at the time so I initially ran it without the controller. The pump simply ran all the time the ignition was on. The only difference was that after a 12 mile run the water temp; was slightly below "N" but the heater was only just luke-warm. So the EWP did its job or circulating water very well. I then added the controller, and this controlled the water temperature at "N" perfectly. I was using standard Bluecol antifreeze at the time. The heater was still pathetic though. So after querying this with Davis-Craig they sent me a discounted motorcycle water pump for the heater circuit. I plumbed this in the heater pipe and arranged to switch it via the heater-motor blower, so it only pumped when the blower was on.
And it just worked. It was a fit-it-and-forget-it solution. And yes, my main D.C. pump was fitted in the lower hose from the base of the rad; That way it pumps cold water and the pump itself runs cooler that if it was pumping hot water.
The controller doesn't vary the speed of the pump. It mark/ spaces the 12V supply, say 10 seconds on and 20 seconds off and gives it a 10 second burst when the ignition is first switched on. I have an early controller without the LCD display btw.
HTH,
Tony.

[soe8m]

Do I want a working heater? Yes or no are two different setups.
Jeroen

I don't know what you mean Jeroen.

The heater works (as well as it does with an 82 degree thermostat that is ),
it is plumbed in with the feed coming from the cylinder head
and the return going to (before) the water pump.

Ian.

When you want the system to run without a mechanical thermostat you can fit in a temp switch like a electric fan sensor switch. The ewp is then your thermostat. For example using an 80 degree on/off switch you can use to power the controller, maybe you can switch the +15 through that temp switch. When warming up the engine the ewp does never run because the controller does not get power below 80 degrees. The size of the radiator is not importand because no flow. When reaching operating temp of 80+ degrees the controller starts doing it's job controlling the flow and keeping the temp on for example a preset temp of 85 degrees. This way the ewp setup acts like a thermostat. More or less flow through the rad. Keeping the engine around normal operating temp. Does it cool down too much due freezing conditions the ewp controller looses power and stops etc etc.

The downside is that during warming up there's no flow through the heatermatrix because no pump is running so almost no heater. When its hot outside and the ewp spins at max then you have your heater but probably not needed then.......

Do you want a working heater from cold you cannot without flow through your heater and a thermostat blocking the flow through the rad. You can use the original thermostat but have to plump in the heater different. You have to move the connection from the original pump to the ewp. You can also use an universal inline thermostat. This way the backpressure is non existent because during warming up the ewp can pump free through the engine and your heater when turned on. When all is hot the inline thermostat opens and also flows through the rad. When the temp rises the controller does make the ewp spin more. This way you have a mechanically control of the temp without back pressure and a working heater.

Those are the two different setups what i do mean. They both will work and keep the engine's temp ok and will benefit a bigger rad for hot weather. In this case the size does not matter for warming up. But the cheap simple methode will not have a decent heater in the winter because the ewp will not be running all the time. The last setup requires more parts and there will be more hoses and t pieces.

Jeroen

[zombeh]

I think the only way you're going to get the water to go where you want it when you want it at the right temperature is to remove the stat, block the bypass and put a remote stat in the top hose where you can run its bypass down to the pump inlet easily.

[gmsclassics]

Just for clarification, I have the latest LCD controller (8000) on my setup, coupled with the alloy 115 lpm pump (picture below). So the operation of the pump I described in my earlier post is applicable to this controller and I don't know if the earlier model is exactly the same. Mine is fitted to the race car and I only really have experience in that situation. It certainly is a significant improvement on a standard waterpump set up when racing so it logically follows that in normal (gentle) road driving it could be somewhat of an overkill. Heater always works fine. It is also worthy of note that my coolant flow has been modified, to that a number of others on the forum have done, with a replacement header tank high up with a 1/2 in hose connected from that to the bottom hose (before the pump), plus bleed feeds from the radiator top and the standard one from the thermostat housing.

One thing I have learned from the race car setup is the value of having the pump and fan continuing to run after the engine is stopped until the set temperature is reached. As a consequence I have rewired the radiator fan and relays on both my road cars so they are fed from the always live fuse source rather than live only when ignition is on. They can also run on until cut off by the thermoswitch, rather than off when the ignition is turned off. That does also seem to make significant difference as quite often when I get home the temperature gauge is reading 90 rather than the 82 it cruises at (only because the last part of the road to where I live rises 200m over a 3 km stretch of lovely fast twisting roads and I just can't resist putting my foot down).

I'm interested to see how you both get on with the mod DC suggest and how this then performs both in your current colder temps and again how it copes with heavy traffic on hot summer days. Even if you have to take the thermostat out every spring and put it back in the autunm, that is such a simple task that it is well worth it if it provides peace of mind of a cooling system that works in all conditions. It is certainly a modification I am seriously considering when I next have a mechanical pump failure.

DC 115 kit.jpg (38.29 KiB) Viewed 971 times

Geoff

[sprint95m]

First off....

Had a reply from Davies, Craig....



Hello Ian,

Thank you for your email relating to the engine temperatures of your Triumph Dolomite.
In some climatic conditions, the engine temperature may not reach the set/targeted threshold during normal operating conditions, especially among some smaller engines.
We suggest in your circumstances to replace the thermostat in order for you to retain the required operating temperature in your engine. You will need to drill 2 x 5mm holes in the thermostat plate if you replace it. The EWP and EWP/Fan Digital Controller combo will continue to manage your engine’s cooling function as designed.

Please come back to me if you have any further questions.


Kind Regards,
John F Benson
JOHN F BENSON
Sales & Marketing Manager




I am going to try this as a temporary measure,
even though I know it will place extra strain on the pump.



Ian.

Tried that and it doesn't work at all. In fact it makes the car undriveable!
When the EWP kicks in the engine near stalls, after all the EWP is trying to force 13 litres of coolant through two 5mm holes within 10 seconds.

This trick/bodge may well work on a car with an expansion tank but certainly doesn't work on one with a header .
Furthermore, from a Saab 99 forum I gather that EWP life expectancy can be reduced to 4000 km

Do I want a working heater? Yes or no are two different setups.
Jeroen

I don't know what you mean Jeroen.

The heater works (as well as it does with an 82 degree thermostat that is ),
it is plumbed in with the feed coming from the cylinder head
and the return going to (before) the water pump.

Ian.

When you want the system .............. The last setup requires more parts and there will be more hoses and t pieces.

Jeroen

Thanks Jeroen for the explanation. It is the latter that I am striving for .

I think the only way you're going to get the water to go where you want it when you want it at the right temperature is to remove the stat, block the bypass and put a remote stat in the top hose where you can run its bypass down to the pump inlet easily.

Yes, I had already concluded that.
Same principle, but slightly different method, keeping the fan sensor in the top hose and retaining the original thermostat in its existing location
I am thinking of installing a hose tail into the inlet manifold, which is what they did on the TR7 EFI.


I am intending to convert to EFI next winter using the TR7 EFI inlet manifold I purchased earlier this year.
Right now I feel that I have simply wasted a lot of money on this EWP and controller,
so I think I should use part of the money I have put by for the EFI conversion to buy a proper pump.
Not impressed.




thanks,

Ian.