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Electric water pump and potential heater issues?


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#1 _triumph202_

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Posted 22 January 2012 - 12:42 PM

Hi, I was just wondering if anyone has fitted a Davies Craig electric water pump to a 202; and could tell me if they've had issues with the cabin heater not working?

I was reading that there can be problems with a lack of water circulation through the heater core; to me, the set up on the 202 engine looks like it might be one of those vehicles? I've got one heater hose coming off the factory water pump inlet and the other off the thermostat mounting block (so, one before the water pump - which I assume is the inlet to the heater core- and the other after the pump.)

With the electric water pump it will be mounted in the lower radiator hose (ie. before both heater hoses.) I was thinking about trying to relocate the heater core inlet hose to the lower radiator hose prior to the electric water pump? Any thoughts?

#2 _oldjohnno_

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Posted 22 January 2012 - 04:48 PM

Yes you've got it all worked out but the hose going to the water pump inlet is the heater outlet. So just move the existing heater hose from the inlet of the original pump to the inlet (radiator) side of the new pump. The other hose can stay where it is.

#3 _triumph202_

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Posted 22 January 2012 - 05:33 PM

Ok thanks. It will be fitted up "as is" for now because I drilled out the blanked heater hose hole in the pump earlier today :mellow: .... and I'll need to sort out a T junction to splice it into the bottom radiator hose.

I've just been out fitting the "modified" factory water pump (impellor and shaft removed) and I noticed there is a another small coolant outlet just prior to the pump impellor. This one appears to feed up to the head via a hole about 8-9mm diameter? Given the small size it can't be anything major - like the path for cooling the head?

Edited by triumph202, 22 January 2012 - 05:34 PM.


#4 _oldjohnno_

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Posted 22 January 2012 - 06:20 PM

You might be lucky enough to have enough circulation as it is to make the heater work - it's certainly worth a try. But if it isn't enough you'll have to make the adaptor.

That little hole is a bypass to allow a little circulation through the head and block while the thermostat is closed, thus preventing any hot spots. It also helps a little bit with purging air from the front of the block at the initial fill. Keep it open.

#5 _triumph202_

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Posted 22 January 2012 - 09:04 PM

Cheers Oldjohnno, thanks for the info.

I'll post up some pics in the next couple of days of how it's progressing. The end goal is freeing up enough space to run twin electric thermofans and to improve the currently marginal cooling system. (Marginal due to the cramped set up in the Triumph 2500 engine bay.)

#6 _coupe202_

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Posted 22 January 2012 - 09:30 PM

What rad are you running and thermos are you thinking of running.

#7 _triumph202_

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Posted 23 January 2012 - 01:38 PM

The radiator appears to be a Kingswood size (triple) core with the filler cap removed (fitted inline in the top hose.) I'm looking at ordering 2 x 10" Spal thermofans- space is VERY tight in the engine bay (I had to modify the factory water pump to gain some space, hence the electric water pump.)I've got just over 50mm clearance between the crank pulleys and the core. It was running a "cut down" version of the stock metal fan with no shroud, plus some nasty metal/ aluminium bladed thermo on the front (about 10" diameter, once again no shroud around the blades) that was next to useless. Installing aircon is also an end goal, so the cooling system needs to be a lot better than it is. I've already got the mounting brackets off an early (VB/VC?) Commodore for the compressor. The battery has also been relocated to the boot to free up space!

Edited by triumph202, 23 January 2012 - 01:42 PM.


#8 _coupe202_

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Posted 23 January 2012 - 07:49 PM

Try a set Ford mondeo thermos for size

#9 _triumph202_

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Posted 23 January 2012 - 08:51 PM

Would they be 50mm deep or under? It's hard to find anything that thin even in aftermarket fans.

Just did a bit of searching and it seems they're 70mm deep, so no go for me. http://www.gmh-toran...eo-thermo-fans/ It's a shame because they look like a near perfect fit.

#10 _coupe202_

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Posted 25 January 2012 - 05:57 PM

Get rid of the kingswood rad and i would fit a custom alloy rad so you can fit the mondeo thermos as I have done

#11 _triumph202_

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Posted 25 January 2012 - 09:27 PM

The problem is the lack of engine bay space, to fit the 202 into the Triumph 2500 the radiator is already been recessed into the top support panel. Even a custom radiator wouldn't gain me more space- from what I've seen the alloy radiators are generally a lot thicker too?

I've just ordered two Spal 10" fans which will cover the radiators width perfectly. I know a shrouded twin fan assembly would be a lot better, but there simply isn't the space. :furious:

#12 _triumph202_

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Posted 25 January 2012 - 09:47 PM

Here are some pics of the work so far....

Thermostat housing with the EWP controller temperature sender screwed in; it's screwed in on an angle because it would hit on the bonnet if screwed straight in from the top :
Attached File  IMG_3335 (Small).JPG   58.2K   5 downloads

The new water pump (destroyed!) and machined down to allow clearance for the fans:
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The chromed brass plugs and stainless bolt to hold the brass "plugs" in place and seal the pump housing. There's also a stainless screw tapped into the water pump breather hole - just in case the inside plug leaks:
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The engine bay in front of the engine- you can see the support panel cutout for the radiator, there isn't a lot of space once the radiator is bolted in:
Attached File  IMG_3345 (Small).JPG   66.02K   4 downloads

These are the fans I've got on order : http://www.spalusa.c...C.PDF#view=FitH

Tip for the day...... water pumps are very hard to strip down. Even a hydraulic press had trouble pushing the shaft / bearing assembly out of the housing!

And a thankyou to my Father inlaw for "customising" the alloy pump housing on his lathe and the use of his hydraulic presses. ;)

Edited by triumph202, 25 January 2012 - 09:48 PM.


#13 _triumph202_

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Posted 04 February 2012 - 12:23 PM

Some progress pics:

Attached File  IMG_3369 (Custom).JPG   33.31K   3 downloadsAttached File  IMG_3370 (Custom).JPG   46.01K   2 downloadsAttached File  IMG_3371 (Custom).JPG   43.17K   2 downloads

Originally I was going to hang the waterer pump inlet directly off the bottom radiator outlet. But , it would have hung so low that it would have been the first part to hit on a high kerb!

The thermo fans have arrived and will be getting fitted today.

#14 _triumph202_

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Posted 07 February 2012 - 09:57 PM

Nearly done, just some wiring to finish. Clearance is tight between the power steering V belt and the RHS fan motor (about 2-3mm!!) but it fits. Worst case I can gain another 2 - 3mm of clearance by removing the rubber gasket between the fans and the radiator core. I figure the engine should rock sideways so it should be fine.

Attached File  IMG_3378 (Custom).JPG   41.69K   2 downloads

Edited by triumph202, 07 February 2012 - 09:58 PM.


#15 _triumph202_

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Posted 23 March 2012 - 01:03 PM

Some more questions/ observations.....

I'm now faced with the problem of the engine running too cool on cold mornings- it struggles to get over 75 unless I get caught at traffic lights. The thermostat has been removed and I'm running the Davies Craig EWP Controller (which "pulses" the pump when under temp.) Fitting a thermostat won't be good (for the EWP) because I've lost the "bypass" circuit using the heater core (due to the location of the standard heater hoses/ location of EWP in the lower radiator hose.)

Considering my options I think the best way to "fix" the problem is either:
a. modify the EWP Controller to slow the water flow further ( at the risk of the head overheating due to the slower water flow?)
b. move the heater core inlet (?) from the (gutted) mechanical water pump housing to before the EWP and install a thermostat in the factory position.
c. Any other suggestions?

PS: Out of interest, in reference to my original post, the heater performance isn't too bad.

Edited by triumph202, 23 March 2012 - 01:04 PM.


#16 _coupe202_

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Posted 23 March 2012 - 10:45 PM

I had the same issues when i fiitted EWP water pump with temp not getting to correct temp just fit a thermostat it will solve all your problems.

#17 _Bomber Watson_

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Posted 24 March 2012 - 08:10 PM

I wouldnt be to worried about not having the thermostat bypass, i've never ran it and never had a drama, that said i have heard bad stories, perhaps just worth a go??

Bang a thermostat in there and see how it goes methinks.

Cheers.

#18 _triumph202_

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Posted 24 March 2012 - 09:35 PM

I was just thinking that without the bypass circuit the water pump will be pumping into a dead end when the thermostat is closed- which wouldn't be good for it? There's a significant flow that would be blocked too- I left the cap off the radiator once..... and then there was the time the top hose blew off- coolant everywhere both times!

#19 _Bomber Watson_

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Posted 24 March 2012 - 09:51 PM

Not entirely, there is generally a small bleed valve in the th ermostat.

Have you considered some kind of controller that may do a better job than the davis craig one?? Ie one that basically stops the coolant untill its up to temp??

And on a side note, if your running 75 deg on a cold morning, thats not to bad really, and iw ouldnt be to worried??

Cheers.

#20 _oldjohnno_

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Posted 25 March 2012 - 10:08 AM

...Bang a thermostat in there...
Cheers.


What he said.

It'll run against a dead head with no problems, but a 1/8" hole through the thermostat will allow a bit of circulation and help prevent getting an air lock in the head if the water level is low.

#21 _triumph202_

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Posted 26 March 2012 - 05:04 PM

I was thinkimg about it and if the heater valve is turned off then there won't be a lot of flow anyway! :)

I might investigate the controller side of things to see if that is an option. I'm just no keen on running the pump against a restriction to the flow.

#22 _oldjohnno_

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Posted 26 March 2012 - 06:07 PM

I was thinkimg about it and if the heater valve is turned off then there won't be a lot of flow anyway! :)

I might investigate the controller side of things to see if that is an option. I'm just no keen on running the pump against a restriction to the flow.


One of the characteristics of centrifugal pumps is that they draw less power as the output is restricted. So even though the pressure will be higher the load on the pump and motor will be quite low.

#23 _triumph202_

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Posted 15 May 2012 - 08:38 PM

I thought I'd post an update on the cooling issue (ie. coolant temp not reaching operating temp in cool weather.)

I Emailed Davies Craig and initially the response was very prompt. However, the reply was far from satisfactory - basically the advice was to restrict the coolant flow by with fitting a restrictor in place of a thermostat, or refit the thermostat!? :banghead: So much for their expensive EWP Controller doing the job...... Perhaps they should read some consumer law, like where it says items sold "must be fit for the purpose"!

I responded back that I didn't want to refit a thermostat- and perhaps their engineers could look into a revamp of the EWP Controller software. eg. change the timing of the pump cycling in the area from 20 degrees below the set temp. After that I've had nil response. (I also doubt I would be able to refit a thermostat given I've got the EWP Controller temp sensor tapped into the thermostat housing.)

I'm going to investigate making my own controller using a microcontroller - they're cheap and it shouldn't be too hard to get a more satisfactory result. So, I've now got a new project..... :)

BTW the heater works reasonably well - providing the coolant gets up to temp. :mellow:

Edited by triumph202, 15 May 2012 - 08:40 PM.


#24 _coupe202_

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Posted 15 May 2012 - 09:15 PM

I had the same problem when I fitted the EWP to my engine and had the same issues with the tempnot reaching temp so I fitted a Thermostat and drilled a 5 mm hole in the thermostat the engine gets to temp and works the way it should.
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#25 _triumph202_

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Posted 16 May 2012 - 10:15 AM

I'm hesitant to refit the thermostat: 1. My temp sensor for the EWP controller is drilled into the thermostat housing and will quiet likely foul on a thermostat if I fit one 2. I don't want to reduce the cooling capacity (ie. max coolant flow) because the plan is to fit aircon (...eventually) 3. I've read where a few EWP's have failed and the people have suggested the failure was due to using the EWP with no controller and a thermostat fitted 4. The EWP system should work without one!!! My plan is to use componentry something along these lines (using the Davies Craig EWP controller temp sensor as an input): http://www.jaycar.co...w.asp?ID=XC4210 http://www.jaycar.co...w.asp?ID=XC4244 http://www.jaycar.co...w.asp?ID=XC4258 Putting it together (hardware/ wiring) won't be a problem, but the programming side of it will be a steep learning curve. ;)

Edited by triumph202, 16 May 2012 - 10:17 AM.





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