Glenn

Impressive circuit Rob! I'll maybe take you up on that after I get all the other gremlins fixed. I'm not sure my system could hold a truly consistent temperature as the thermoswitch has a 10 degree range (100 on, 90 off).  The temp gauge sits steady at about 1/3 on the move (as always), rising slowly  to about half when sitting idling for a good few minutes. That's less deviation than my 80s watercooled VW van with factory electric fan. If I can pick up a 95-90 switch I reckon that will be about bang on, meanwhile I reckon it's not bad. I doubt the fan will be on much as it will rarely be driven in traffic or sit at idle for long. Thanks again all.

Rob you are a bad influence. I can't resist a bit of far too complicated so feel free to give details about how it's done here please!!

That's what I was thinking. I did have a think about a 3 relay timer system to allow fan to run on for a fixed period, but gave up and saw sense as far too complicated!!

Got the fan installed - parts sourced from eBay for a bit under £50. I was able to try it out at the weekend and it seems to work well enough. Fan only kicks in if the car has been sitting idling for a good while, and it gets temperature down fairly quickly. Plenty of room under the nose panel, but I took the radiator out to fit the fan as I was a bit worried about damaging it with the cable ties. I wired the relay coil through the ignition, and took a fused feed off the battery to power it. If I was doing it again I'd probably just make the relay coil feed permanently live so it could run on after the engine is off.

Thanks all. Relays seem to make sense in that case. I like the look of the double relay unit Howard posted, neat and cheap, although the carriage from Europe adds a fair bit so would be glad to learn of any UK suppliers for those or similar. Cheers.

Thanks again folks this has been very helpful. I'm going to try one of those cheapy fans. I'll power the relay coil through the ignition circuit, but if I find it often needs to run after the engine is stopped, I was planning changing to a 5 pin relay and timer relay set so fan can run on for 30 seconds or so. I'm a bit worried about more than that as the battery is quite small. Car is getting a mildly updated alternator however as have one lying about, and the old one's bearings sounded rough. I'll let you know how it works or otherwise.

I had a real struggle last week trying to get a sealed beam, and the one I did get hold of  "popped" very quickly!  A Halogen conversion seems to make sense but I have a couple of questions I was hoping folk could help with please? Are the standard wiring and switches up to the Halogen bulbs or will I need relays?  Also, from looking at the wiring diagram (1977 4 speed TR7) I am confused as it looks like the headlights have separate fuses, but the only fuses I can find are the 4 in the lucas box, and an inline each for the radio and heated screen which are also in the cubby box.  Just asking because I seem to remember some older cars with sealed beams didn't have fuses, I suppose as the beam would blow if there was a problem. Any advice greatly appreciated.

Thanks Glang. I can see some trial and error will be needed, and a close eye kept on the temperature gauge.  It's not had any cooling problems since I've had the car.  There's plenty room either side of the radiator.  Are there any specific advantages of the fan being a puller or pusher?  Is it an advantage to allow it to run on after the engine is off?  Just wondering if that does much good when the water pump isn't pumping?

Thanks all. I've removed hub and coupling now to have a better look, and both are in poor shape. Purely for cost reasons I'm going to go for an electric fan. The surface sensor sounds great but I wasn't able to see any online unfortunately. I've gone for a revotec style with switch which cuts in at 100 degrees and off at 90. The switches are pretty cheap if I need to vary that. I reckon that should hopefully keep it out of danger but keep above 88 so the thermostat doesn't close. Thanks again. 

Not posted for a while as my TR7 (1977 4 speed) had been laid up for a few years. Looks all new here! Anyway, just recommissioned the car and on the first proper outing the viscous fan packed up, making a terrible noise.   I'm not fussed about originality, and was thinking I would go with an electric fan and thermoswitch. I'd prefer to cut the top hose and fit a Revotec type switch unit rather than the Kenlow probe which I've found in the past can drip. My question is, if I go for a fixed temperature switch, what cut in/ cut off temperature should I look for? Anything else I need to be mindful of?   thanks, Glenn

Sorry I'm probably a bit late posting Lloyd, not been on here for a while.  I have a mk2 lower rear valance you can borrow if you want.

Like Andy says, check out Car SOS - it was to the Zodiac they fitted a clutch servo.  Looked simple enough in the show and seemed to do the job nicely.

Try Chris Witor - he sells needles for special applications.  Think it's BAE he supplies for early PI spec on HS6s, a bit richer at the top end than standard TC/S.

I've 2 saloons.  One is fine, the other will need sills and rear arches before it can go back on the road.  I'm in northern Scotland - whilst I have no way of knowing what's parked up in sheds waiting to be saved, there don't appear to be many 2000s left now up here.  I know of a couple each of estates and saloons hidden away - all would need outer sills and most arches amongst the other bits that are easier to fabricate. It doesn't seem at all right that you are out of pocket Lloyd - it's a pity this couldn't be shouldered by a club.   You are going a very worthwhile job, thank you very much indeed.

Could you have an air leak?  Carb gaskets all ok?  If you had the manifolds off when you replaced the water pump, did you use a new gasket?  Worth ruling out.