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Following up on another thread about cooling here , I thought I'd share my write up of using an Electric Water Pump as a replacement for the mechanical one on my 9000. Parts of it may well be relevant for other models too.
OK, here’s the full story…
Since fitting the Abbott intercooler last year, I noticed a significant increase in coolant temperature on hotter summer days. Because mine is a MY93, the gauge reads real temperature, unlike later ones which will stay pretty much level once warmed up until temps rise a lot. The reason for this temperature increase is that in order to achieve a good temperature drop whilst being very free flowing, the Abbott intercooler must have to increase the cooling fin are which will in turn further restrict the flow of air to the radiator.
I know that 9000's, especially when tuned, can run hot and after noting the info in the CCC article about the Abbott 9000 about the mechanical water pump cavitating at higher revs, I decided the "easy" way forward was to use an electric water pump (EWP) rather than look at trying to improve air flow. There are essentially two options for installation- as a boost to your existing pump or as a replacement. I decided on the latter.
To replace your existing mechanical pump, you use an EWP controller and remove the mechanical thermostat. In its place you insert a temperature sensor that feeds the EWP controller. Basically, as things heat up in the block, the controller increases the speed of the pump. You can set whether you want the system to run cooler (more power) or warmer (more economy).
The recomended location for the EWP is in the bottom hose of the radiator that feeds in to the water pump. It's a complete pig to fit in there on a 9000, believe me. You also have to get two straight flange adaptors ratehr than one staright and one right angle that come with the kit. I'll post a pic later...
You then have the option of either removing the mechanical impeller from the pump or using a shorter belt to bypass the pulley. I chose the former and ordered a new water pump from ECP that I then removed the impeller from with an angle grinder (messy but effective!).
Once in, and leaks sorted, all seemed to be OK, but I was pulling air in as noted. The pump could be seen to have a varying voltage applied to it according to engine temp. Bear in mind though that this was a month or so back when ambient temps were a lot lower.
I did have a problem with lack of flow to the heater matrix, which their info did say might happen. To counteract this, I ordered a smaller booster pump and fitted it to the circuit.
The problem, however, with this, was that it's flow rate was so high that it increased overall temps as it was clearly preventing the main flow from the bigger pump getting in to the block effectively. No problem, thinks I, I'll just reduce the voltage to it. Except that unlike the bigger pump, which runs from about 2 to 13.5V, the motor isn't really designed for this and although I achieved a partial reduction, it wasn't enough.
All this became apparent in the last day or so leading up to the track day at Goodwood, and even without the smaller pump running temps were still higher than before so on the way down I decided the thing to do was put in a bypass switch to feed 12V directly to the pump. Fortunately, Halfords were still open at 7.30pm and I managed to grab a handful of suitable bodgery. Unfortunately I didn't have a multimeter and the following morning at about 6.50am managed to make an incorrect assumption about the controller wiring that resulted in a spark and a dead controller
.
Meanwhile, whilst down at Abbott the other week I asked them what could be done, and had teh following very useful advice which I intend to put to use soon...
1. Use a raditor from an automatic- apparently they're a bit more efficient
2. Drill holes in the wheel arch liners to let the heat out (Mark A, do you have the pic?)
3. Remove the seal from the aquarium and pack up the rear of the bonnet with 5mm spacers.
4. For track days, remove the mesh grille which is fairy restrictive.
So, after a lengthy (and costly) period, I've come to the conclusion that an EWP doesn't really work on a 9000 for a variety of reasons, and I shall revert to the mechanical pump and use the EWP as a booster to maintain a high flow for track days. I will probably also wire it in with a run on timer/stat for everyday use to help eliminate heat soak.
OK, here’s the full story…
Since fitting the Abbott intercooler last year, I noticed a significant increase in coolant temperature on hotter summer days. Because mine is a MY93, the gauge reads real temperature, unlike later ones which will stay pretty much level once warmed up until temps rise a lot. The reason for this temperature increase is that in order to achieve a good temperature drop whilst being very free flowing, the Abbott intercooler must have to increase the cooling fin are which will in turn further restrict the flow of air to the radiator.
I know that 9000's, especially when tuned, can run hot and after noting the info in the CCC article about the Abbott 9000 about the mechanical water pump cavitating at higher revs, I decided the "easy" way forward was to use an electric water pump (EWP) rather than look at trying to improve air flow. There are essentially two options for installation- as a boost to your existing pump or as a replacement. I decided on the latter.
To replace your existing mechanical pump, you use an EWP controller and remove the mechanical thermostat. In its place you insert a temperature sensor that feeds the EWP controller. Basically, as things heat up in the block, the controller increases the speed of the pump. You can set whether you want the system to run cooler (more power) or warmer (more economy).
The recomended location for the EWP is in the bottom hose of the radiator that feeds in to the water pump. It's a complete pig to fit in there on a 9000, believe me. You also have to get two straight flange adaptors ratehr than one staright and one right angle that come with the kit. I'll post a pic later...
You then have the option of either removing the mechanical impeller from the pump or using a shorter belt to bypass the pulley. I chose the former and ordered a new water pump from ECP that I then removed the impeller from with an angle grinder (messy but effective!).
Once in, and leaks sorted, all seemed to be OK, but I was pulling air in as noted. The pump could be seen to have a varying voltage applied to it according to engine temp. Bear in mind though that this was a month or so back when ambient temps were a lot lower.
I did have a problem with lack of flow to the heater matrix, which their info did say might happen. To counteract this, I ordered a smaller booster pump and fitted it to the circuit.
The problem, however, with this, was that it's flow rate was so high that it increased overall temps as it was clearly preventing the main flow from the bigger pump getting in to the block effectively. No problem, thinks I, I'll just reduce the voltage to it. Except that unlike the bigger pump, which runs from about 2 to 13.5V, the motor isn't really designed for this and although I achieved a partial reduction, it wasn't enough.
All this became apparent in the last day or so leading up to the track day at Goodwood, and even without the smaller pump running temps were still higher than before so on the way down I decided the thing to do was put in a bypass switch to feed 12V directly to the pump. Fortunately, Halfords were still open at 7.30pm and I managed to grab a handful of suitable bodgery. Unfortunately I didn't have a multimeter and the following morning at about 6.50am managed to make an incorrect assumption about the controller wiring that resulted in a spark and a dead controller

Meanwhile, whilst down at Abbott the other week I asked them what could be done, and had teh following very useful advice which I intend to put to use soon...
1. Use a raditor from an automatic- apparently they're a bit more efficient
2. Drill holes in the wheel arch liners to let the heat out (Mark A, do you have the pic?)
3. Remove the seal from the aquarium and pack up the rear of the bonnet with 5mm spacers.
4. For track days, remove the mesh grille which is fairy restrictive.
So, after a lengthy (and costly) period, I've come to the conclusion that an EWP doesn't really work on a 9000 for a variety of reasons, and I shall revert to the mechanical pump and use the EWP as a booster to maintain a high flow for track days. I will probably also wire it in with a run on timer/stat for everyday use to help eliminate heat soak.