andyborris
Posted a lot
Freedom is just another word for nothing left to lose.
Posts: 2,218
|
|
Jul 10, 2016 17:47:43 GMT
|
|
It's for a BMW M52 engine, it's normal operating temp is 95*C, the thermostat starts to open at 88*C.
The car has a MK2 Golf GTI rad, so I have a choice of 2 rad fan temp switches to control the rad fan, one is on at 95*C and off at 90*C, the t'other is a on at 95*C and off at 85*C.
So which should I install, having boiled one engine down to a lump of aluminium, I'm wary of doing it again!
Thanks
|
| |
|
|
|
|
andyborris
Posted a lot
Freedom is just another word for nothing left to lose.
Posts: 2,218
|
|
Jul 10, 2016 18:28:31 GMT
|
|
Having thought about it some more, it's got to be the 90/95*C one, the 85/90*C version will cause the thermostat to shut....!
|
| |
|
|
|
|
|
Jul 10, 2016 19:08:29 GMT
|
|
Hi, If you don't want it to get too hot you need the fan to come on early, the thermostat will stop it getting too cold so let it do it's job.
Having said that I think the golf rad may be under specced. Power equals heat, so depending on the power of the engine and the power of the car the rad came from, there could be a more heat from the engine than the rad can deal with.
Colin
|
| |
|
|
ChasR
RR Helper
motivation
Posts: 10,296
Club RR Member Number: 170
|
|
Jul 10, 2016 21:49:21 GMT
|
|
Indeed. Considering the M52 is not exactly known for being mega robust always I'd look into potentially fitting a larger radiator.
FWIW my old Ford Mondeo's thermostat was an 88 degree one. The fans came on at 100 and turned off at 95. In the high speed mode they came in at 105 degrees.
IMO either thermostat would be fine.
|
| |
Last Edit: Jul 11, 2016 6:32:04 GMT by ChasR
|
|
|
|
|
|
|
|
90/95 will work fine, coolant at pressure doesn't boil till 130+.
|
| |
|
|
andyborris
Posted a lot
Freedom is just another word for nothing left to lose.
Posts: 2,218
|
|
Jul 11, 2016 18:03:41 GMT
|
The original engine boiled because I'd used the BMW ECU to control the rad fan and it tried to switch a single speed fan to it's higher speed! And I didn't notice that the fan had stopped till too late. The Golf rad is the only one that fits at a reasonable price. However, it is a twin core alloy one, that according to the sales pitch, is " 30% uprated and can support 350 BHP engine power" (actual colour of words, so must be true) !  Time will tell....... |
| |
Last Edit: Jul 11, 2016 18:19:28 GMT by andyborris
|
|
scimjim
Club Retro Rides Member
Posts: 1,503
Club RR Member Number: 8
|
|
|
|
|
The locost guys run v8s and bike engines with a £35 polo plastic/alloy eBay rad (because it fits the 7 nose cone) - I run one on a standard CA18ET and had no problems on a test day or long traffic jams after high speed runs. As long as it can flow the volume and transfer the heat (which really, any modern rad can do as the running temps are all in the same range no matter what the engine).
Don't forget if the sensor is at the bottom of the rad, or halfway down, the temp can be several degrees different to the engine temp (usually read off the head near the stat).
|
| |
|
|
ChasR
RR Helper
motivation
Posts: 10,296
Club RR Member Number: 170
|
|
Jul 12, 2016 10:23:29 GMT
|
A Locust probably weighs less and drags far less than an old Triumph as well  . The Triumph will also have poor radiator ducting access from the front ; I know it's one reason why the Stags were said not to be good at cooling and simple things like a valance spoiler make a massive difference, it did on my car with the new owner; The Mk1 2000s look worse here. As for a transfer of heat a heater matrix *can* keep a car cool, but let's be honest it's only just . I've just had an idea Andy. Could you not still use the BMW ECU to govern the fan but get a twin speed fan, thus it would operate as intended? |
| |
Last Edit: Jul 12, 2016 10:24:28 GMT by ChasR
|
|
|
|
|
Jul 12, 2016 12:11:25 GMT
|
|
that polo rad is most likely the same as a vr6 rad which is what has been used on many v6 peugeot conversions.
|
| |
|
|
scimjim
Club Retro Rides Member
Posts: 1,503
Club RR Member Number: 8
|
|
Jul 12, 2016 12:55:01 GMT
|
that polo rad is most likely the same as a vr6 rad which is what has been used on many v6 peugeot conversions. Just checked and the VR6 rad is 630x380 (core), the polo is 380x320. It doesn't state depth but modern rads have much more to do with packaging than classics/retros - apart from the mini perhaps  |
| |
|
|
|
|
ChasR
RR Helper
motivation
Posts: 10,296
Club RR Member Number: 170
|
|
Jul 12, 2016 23:39:40 GMT
|
|
|
| |
|
|
hario
Part of things
S202 C300STD
Posts: 421 
|
|
Jul 13, 2016 15:55:21 GMT
|
|
If the Golf rad has 2 fan switches can't you use the 2 switches wired to 2 fans for lo/hi 'fanning'.. ?
|
| |
*S202 C300TD Wagon*
Installed:
OM606 & 722.6, Evo6 IC, S600AMG callipers & 345mm rotors. No catz. Leatherish seats.. Rust..
Future:
DIY manifolds & turbo compound build.
Built IP, & some kind of software. Less rust..
|
|
Rich
Club Retro Rides Member
Posts: 6,320
Club RR Member Number: 160
|
Which Rad Fan Temp Switch To Use?Rich
@foxmcintyre
Club Retro Rides Member 160
|
Jul 13, 2016 17:10:54 GMT
|
If the Golf rad has 2 fan switches can't you use the 2 switches wired to 2 fans for lo/hi 'fanning'.. ? It has one switch but a choice of 2 switch temperatures you can fit. There isn't 2 switches physically fitted. |
| |
|
|
andyborris
Posted a lot
Freedom is just another word for nothing left to lose.
Posts: 2,218
|
|
Jul 13, 2016 17:17:19 GMT
|
|
I think the reason moderns use a hi/lo fan is to reduce NVH, the lo speed makes less noise and the hi speed is rarely on.
I'm not worried about a bit of fan noise, (makes a change from the exhaust racket!) just as long as it brings the temp down!
It's now got a big fan sitting behind the rad and ducting in the nose cone to encourage more air to flow through, rather than around the rad.
The old rad (a standard BMW E30 one) with front mounted fan coped OK (sticky back day in a M25 jam!), till Paris (sweat dripping off face day and a 1000 classics jam!) and the muppet who wired the engine! The Golf GTI one is bigger then the E30 one, so I'm hopeful.
|
| |
|
|
ChasR
RR Helper
motivation
Posts: 10,296
Club RR Member Number: 170
|
|
Jul 13, 2016 22:10:16 GMT
|
|
It will also be down to thermal shock IIRC. Keeping the temperature more 'consistent' should subject the engine to less heat cycles in theory as opposed to the temperature constantly going back and forth.
OK, this is more if you plan to pile on the mileage but it is still a consideration. I know CVH blocks in Fords are now cracking due to too many heat cycles, resulting in the Turbo boys now either going down the Zetec or ZVH route.
|
| |
|
|
hario
Part of things
S202 C300STD
Posts: 421
|
|
Jul 14, 2016 15:24:05 GMT
|
If the Golf rad has 2 fan switches can't you use the 2 switches wired to 2 fans for lo/hi 'fanning'.. ? It has one switch but a choice of 2 switch temperatures you can fit. There isn't 2 switches physically fitted.
oh right sorry I see. That sounds like a switch for each petrol/diesel engine options?
|
| |
*S202 C300TD Wagon*
Installed:
OM606 & 722.6, Evo6 IC, S600AMG callipers & 345mm rotors. No catz. Leatherish seats.. Rust..
Future:
DIY manifolds & turbo compound build.
Built IP, & some kind of software. Less rust..
|
|
. The Triumph will also have poor radiator ducting access from the front ; I know it's one reason why the Stags were said not to be good at cooling and simple things like a valance spoiler make a massive difference, it did on my car with the new owner; The Mk1 2000s look worse here. As for a transfer of heat a heater matrix *can* keep a car cool, but let's be honest it's only just 
