Fitting electric fan to P6 Rover - few simple Qs?

testrider said:
Hi Dave, to be honest there wasn't much info on the Kenlowe site, it seems a bit out of date. I rang a fellow at Kenlowe called Jeff and he was most helpful. Whilst the fan was reasonably expensive I have peace of mind that I have the right part for the job without having to risk my engine with something from a scrap yard that may or may not work.
Click to expand...

Your right, their website is not particularly helpful.

My concern now is the space to fit a more powerful fan either in front of or behind the rad now that I've had it recored to 3 rows (oh and the amount of money I've already spent getting to this stage). I'll measure the space and phone Kenlowe to see if they have anything suitable that will fit. I've already had to make some minor adjustments to the bodywork behind the bumper to get my existing fan to fit on the front of the rad.

Cheers

Dave
 
silly n00b question time... is there a reason people dont just swap for the sd1 or other viscous setup with a decent rad cowling? Does it just not fit?


Rich
 
Good clue with those two fan powers. 265w is fairly clearly going to shift a lot more air than 70w before you get to thinking about size.

Chris
 
rockdemon said:
silly n00b question time... is there a reason people dont just swap for the sd1 or other viscous setup with a decent rad cowling? Does it just not fit?


Rich
Click to expand...

This is what i did, despite the fact that i have a 4 cyl car. The actual viscous unit has been fitted to the nose of the water pump via an adaptor and was common among many cars from the SD1 to the Land Rover 200 TDI engines to the early 1990's. So, you can find one easily even new off the shelf. In this unit you can bolt a variety of fans, either SD1 or Land Rover parts. I chose a big plastic 5 blade fan (with unequal spacing) from a 200 TDI engine. It is quiet, and you can feel that it shifts lots of air even at idle. When you use higher revs, the viscous clutch will do its job, and the fan will not absorb excess horsepower.
The engine will warm up quickly and the temperature will just stay at 85 degrees no matter what, cruising, stationary, slow moving traffic. And over here, in this time of the year, ambient temperatures of 35 degrees and above are common (we don't have much humidity so it is still comfortable :D ). There's no cowling fitted, but the radiator is a 3 row type. There was just enough space for the whole setup, but to be on the safe side, i moved the lower radiator mounting in the first hole. Previously, it has been in the middle.
I liked this solution because it is almost as efficient as an electric fan and (important to me) i kept the electrical system simple, avoiding extra wires, sensors and extra loads on the alternator and battery.

Demetris
 
I'd be sorely tempted given these problems with vapourisation and overheating to go down this route. I didnt run the p6 in warm weather before removing the engine with the knacked piston rings... should find out if it has this problem in a week or two!

Rich
 
Rich, Demetris has a 4 cyl with a lot more space between engine and rad than the V8. My understanding was that in order to fit the viscous coupling in a P6B you needed to have a short nose water pump and that this was now pretty well unobtainable. Certainly this is one of the few mechanical differences between the NADA 3500S and the UK cars. I think Austarlian / NZ cars had this arrangement too. I'm open to correction on this as I've never had the opportunity to measure up the NADA set up against the UK version. Anyone out there have detailed knowledge?

Chris
 
Greetings hotheads,

Following the cooling discussion with great interest because i'm in the proces fitting an electric fan too.

My '69 V8 doesn't have cooling problems in the standard set-up, so my motivation is to save some fuel. If I had cooling problems I would first look at the flow of coolant (pump ok?, coolant level ok?, grutty items in system?, thermostat ok?, radiator not blocked?), then I would check if ignition is not retarded too much (heats up engine). If that doesn't help, last resort: carbs too lean? or exhaust not blokked?
IMHO fitting electric fans don't fix an engine generating too much heat and fans don't fix a failing coolingsystem.

My thoughs about the best electrical fan setup would be:

1) Using the electric signal from the temp gauge is not easy, cos of signal is not linear (rather irratic?). So adding at thermostatic sensor is more handy. But I would put it in the cool side (between rad and thermostathousing). Why not in the hot side? Because the electric fan is nessecary when then the rad can't cool down the incoming coolant enough to feed the engine with cool enough coolant. If the incoming temp of the coolant is high, but the rad is capable to bring down the temp 'on its own', the help of the fan isn't needed.
Other option would be to solder the sensor on the low temp side of the rad but I geuss the sensor would perish doing so.

2) Bigger is better when it comes to the size of the fan. Flowrates increase dramatically when diameter is increased. Curved blades are usually more efficient and more silent, but lose these benefits when running in the opposite direction. 16" would be nice, but haven't found one yet that fits the between rad and waterpump :( . Option would be to invest in a short nosed waterpump (Q:is this a hassle-free fit?)

3) Placement. Realy try to get the fan between rad and engine, because this won't comprimise natural airflow. Favourable position: as far as possible right down on the rad (seeing from engine). Putting the fan on the cool side of the rad gives the rest of the rad maximum opportunity to cool before aid from the fan is needed. And the rad ('on it's own') is most effective on the hot side. If cooling isn't enough, the fan can do the last bit.
Fixing the fan on the rad wouldn't be my first choice because of the danger of damaging the rad by the plastic fixing-pins. Every time the fan is started, it will have a rotating impulse and thus yerks the pins running through the rad.
Creating some sort of a frame to fix the fan(s) is nessecary.

4) Fuse the fan seperately.

Only my thoughs.....

Additions and tips welcome.



Rene
 
This is what i did, despite the fact that i have a 4 cyl car. The actual viscous unit has been fitted to the nose of the water pump via an adaptor and was common among many cars from the SD1 to the Land Rover 200 TDI engines to the early 1990's. So, you can find one easily even new off the shelf...
Click to expand...

Hi Demetris,

I'm looking to do this same mod on my 2000 TC with long nose water pump. Did you have to make up an adaptor plate for the landy viscous unit or are there stock ones from other cars that will fit straight onto the end of the water pump housing?

Fed up with my rattly metal fan vibrating all the time and sapping my much-needed horses on the motorway!! But agree that i want to keep my wiring simple. Bought a cheap thermo control for an old electric fan a few weeks ago but could not get it working! The relay kept current latching and it ran my battery down. It's now in a heap in the back of the shed!! There was much grumbling that weekend...

Michael
 
Hi 68PBBurntGrey.

I do follow your logic for having the thermostat on the cool side of the rad. I am, however, concerned that all major manufacturers do it the other way. I'm therefore keen to find a reason! My best guess is the conditions that prevail at idle after a hard run. The engine continues to release stored heat from the run and as a result the coolant temperature in the head soars. This is facilitated and worsened by a very low coolant circulation rate at idle. I'd say their theory is that they don't want to wait for the slug of overheated water to reach the cold side of the rad. Don't forget the objective is to cool the engine - the rad is just a step along the way - so the motiviation is to trigger the rad fan as far as possible by conditions in the hottest part of the engine. I guess they are prepared to accept the risk of a slug of overcooled coolant chasing the overheated coolant out of the head!

This argument is of course why it was always recommended to have a period at light throttle after a hard run, and not to switch the engine off or allow to go straight to idle after a full throttle run.

Placing the rad fan in front of or behind the rad makes no difference to the air flow obstruction through the rad - unless air is escaping around the sides of the rad to go back to the front for a second run!!!

I'm unconvinced either way as to whether the fan is more effective placed to the hot corner or the cold corner. I accept your argument, but then again the fan will be much more effective acting on a high temperature difference than a lower one - which pushes the fan location to the hot corner. If the fan were to be used only occasionally and its performance wasn't seen as being too critical to the health of the engine, then I think your argument wins. If the fans are used regularely and are a routine part of the cooling set up then I'd plump for the hot corner. Since I can't predict from here how your particular set up is going to behave I think I'd err on the safe side and go for the hot corner.

Chris
 
Hi Chris,

Thanks for your thorough answer! Theory blown anway by practice I guess... :idea:
Key words IMO are 'overheated coolant' and 'idle conditions'.
Both setups aim to cool the coolant in the rad. My major concern was preventing hot coolant returning to the engine and thus prevent overheating. Ignoring the fact, as you pointed out, the overheating at idle after a hard run is caused by a slow flow of coolant with a hot engine: cooling is needed asap.
There is another concern I thought of, the hysteresis of the thermostat. If placed in the cooler side of the rad, it will always be late to switch the fan on. Placed on the hot side (set on an higher switch-point), at least the rad is a kind of 'safety'.

To give you an update on my setup: it's still original Rover with the exeption of a coolant overflow tank. Already bought a variable thermostatic switch and an electric fan from the scrapyard (Citroen 1,9 TZI, dia 31 cm). This fan will fit nicely behind the rad with very little work, but not yet impressed about it's airflow. A 40 cm SPAL (thinline) is backup.

Reading your reply, two Q's came up:

1) Has anyone tried to rev up the coolant pump by reducing the diameter of it's flange? (?? I'm using this board to learn English too :oops: )
2) Is fitting a shortnose pump a hassle? And how much extra room does it generates?

Rene
 
68PBBurntGrey said:
1) Has anyone tried to rev up the coolant pump by reducing the diameter of it's flange
Click to expand...

Reducing the size of the pump pulley will cause the pump to run faster, and therefore in theory flow more, but if that is the case it will also reduce the time that the hot coolant is in the radiator, and hence the time available to cool it properly.
 
redrover said:
I'm looking to do this same mod on my 2000 TC with long nose water pump. Did you have to make up an adaptor plate for the landy viscous unit or are there stock ones from other cars that will fit straight onto the end of the water pump housing?
Michael
Click to expand...

Hi Michael,
unfortunately there is no adaptor available off the shelf. But it is not difficult to make one, if you have access to a lathe. It is just a matter to bring together the water pump and viscous unit and think how they should mate. In my case the adaptor fitted over the pump nose and is bolted to the pump's flange by countersunk allen bolts and nuts. The other side of the adaptor is made to fit snuggly to the viscous' inner bearing and ends up to a threaded shaft. Then, using a large flat washer of a suitable diameter, a spring washer and a nut (or just a nyloc nut) the viscous is tightened to the adaptor.
This is how my setup looks.
 

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Some enterprising person should make a few and sell them on ebay - I'd be up for buying one for a V8
 
Were the water pumps universal across the 4cyl and V8 engines? If so, this should be a straight swap..? Looks like we may be onto something!!

Thanks for your pics, Demetris. I should be able to make something like this up without too much difficulty. :)
 
An SD1 V8 water pump with viscous coupling and fan will not fit within the allocated space in a P6B engine bay. Although the footprint of the water pump is the same as that of the P6B, the nose of the pump is very much longer and even that alone will not fit within the space provided. The viscous coupling is again different, same with the fan.

Ron.
 
Obviously very late to this discussion. I have some experience - fitted elec fan to a Mini, and an 1800 in the day. There is a good discussion here Cooling the Sunbeam Tiger by Tiger Tom and Chuck King – TigersEast AlpinesEast on cooling which covers variations on pumps, fans, cowlings etc.
First, I have an export 3500S with the viscous coupling, 13 blade fan (quite small blades), and in southern Oz summer temps going to mid to high 30C, occasional 40Cs - have never seen the gauge expose the '5' fully. Apart from the viscous and fan being different from home market cars there is also some cowling on the back of the rad - 572730 and 572733. The fan blades are not fully shrouded, but about half the blade width protrudes behind - which somewhere in my reading was reported as optimal, as it moves quite a lot of air outwards (centrifugally) from the tips in addition to the air being moved axially through the inner area of the blades. Sucking fans are more effective than pushers. The specs are in CFM - cubic ft/min.
Another area worth looking at is hot air recirculation - when not moving, hot air behind the rad can get sucked around the front by going under the cross member. Porsche 928 have a shield here to prevent this , and the Sunbeam article above mentions this. I ran 2 x 11" SPAL (Italian) on my 928, and even an 85A alternator was struggling to cope with the load. I have made a baffle to fit between the cross member and the front valance on the Rover to prevent this recirc - only downside is it has to be removed to change the oil filter.
Unless you are fixed on going electric for economy reasons I would suggest getting the viscous coupled pump and fan, or at least fit some cowling around the fan. As for the actual rad, IIRC the sunbeam article reckons more than 3 rows in the core is counter productive. As for sensors, there are many parts that fit into a rad hose and take a screw-in sensor - these come in many settings and threads, M22x1.5 being very common.
www.supercheapauto.com.au

SAAS Water Temperature Sensor Adaptor - 38mm

SAAS Water Temperature Sensor Adaptor - 38mm
www.supercheapauto.com.au www.supercheapauto.com.au
 
Already covered this: My cooling project

Basically use a large fan and sweep the most area of the rad and use a two speed switch, the neatest (and cheapest) solution is indeed to mod the rad with a M22 boss for standard switches. You only need about 80W of power to cool the engine in "normal" mode, those megawatt Kenlowe fans are an utter waste of time and effort and just overload the electrics and make a load of noise. Unfortunately "sucking" fans don't really fit the V8.

Note also proper automotive thermoswitches are not simple on/off devices, the have a gap with a higher "on" point and a 5 degree or so lower "off" point.
 
my tuppence worth . had electric fan fitted (pushing ) 12" and made very little difference . swapped for uprated rad ( Wins international ) and removed fan . ensured rad was full .cap 15psi. removed. 84?degree thermostat. now runs just after midpoint on temp gauge ( running with Evans waterless coolant not anti freeze ) most of time and on Hot sunny days goes to three quarter point . in traffic hot days stays just (just) under red section. so not happy that high but car runs Ok apart from normal fuel vaporisation if parked hot engine for more than 10 mins. having checked other forums It seems best or ideal is what cars have these days = suck through rad but WITH a cowling .seem cowlings greatly increase air flow and ergo better temp control .
 
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