Paul M Posted May 30, 2021 Report Share Posted May 30, 2021 Hi - finally able to get out this weekend and went to a local classic car show. Temp fine when running but because of poor traffic mgt getting into the show we ended up in a stop start traffic jam in warm weather and the temp went up with a lot of steam and water dumped out of the overflow. After letting it cool down we got to the show ok and temp was back to normal for the journey home. When i say normal it is always just past the 185 degrees mark and it runs fine at this temp. Any ideas? Could it be the fan not kicking in? New owner during lockdown so any advice welcome. Quote Link to post Share on other sites
RobH Posted May 30, 2021 Report Share Posted May 30, 2021 I assume you only have an after-market electric fan Paul and not the original mechanical one ? How does the fan get switched - is it automatic or do you have a manual override? It should be obvious from the noise and the current drawn that an electric fan is working. Stop-start traffic can sometimes require that you turn the engine off while stationary. Quote Link to post Share on other sites
RogerH Posted May 30, 2021 Report Share Posted May 30, 2021 Hi Paul, is the fan rotating in the correct direction.? If it is on the rear face of the rad and is pushing the air sdtream then you would be forcing warm/hot air through the rad and the cooling will not be too good. When you get it sorted, fit an override switch and turn this ON if you anticipate a hold up. This will help to keep the temp down. Roger Quote Link to post Share on other sites
Hamish Posted May 30, 2021 Report Share Posted May 30, 2021 great advice above but also consider the temps / gauge indications. Did it get too hot or was there too much water in the rad neck ? This extension shouldn’t be full. A good inch or so below full. my car like yours will indicate 185 + as normal. fan cuts in just before the next mark (207f ?) these temps are 85 and 97c ish still not boiling! and as Roger says a manual override is really useful. Quote Link to post Share on other sites
Nigel C Posted May 31, 2021 Report Share Posted May 31, 2021 I've just fitted two revotech fans and I'm very disappointed with the flow of air. They were the highest value for size they do but nowhere near the clunky old Austin Montego fans I fitted from a scrapyard 25 years ago. I had my techy guys build me a controller as they draw 12amps each and I thought a start up hit of over 24amps a bit of a shock to the electrical system. With my new box of tricks one comes on followed by the second one 10 seconds later. On a thermo switch and an override. Quote Link to post Share on other sites
Ralph Whitaker Posted June 1, 2021 Report Share Posted June 1, 2021 7 hours ago, Nigel C said: I've just fitted two revotech fans and I'm very disappointed with the flow of air. They were the highest value for size they do but nowhere near the clunky old Austin Montego fans I fitted from a scrapyard 25 years ago. I had my techy guys build me a controller as they draw 12amps each and I thought a start up hit of over 24amps a bit of a shock to the electrical system. With my new box of tricks one comes on followed by the second one 10 seconds later. On a thermo switch and an override. I take it they are running the right way round? I have a single electric fan, full width of the rad, running through a relay and thermo switch controlled, the ammeter kicks like mad when it switches on. Took 20 mins to do 100m leaving a show yesterday in 20+ degrees heat, the fan coming on for about 15 seconds every minute, but it did the job and kept everything cool. I had my arm trailing outside the door and could feel the rush of hot air coming out from under the car when the fan was on. Ralph Quote Link to post Share on other sites
John McCormack Posted June 1, 2021 Report Share Posted June 1, 2021 42 minutes ago, Ralph Whitaker said: I take it they are running the right way round? I have a single electric fan, full width of the rad, running through a relay and thermo switch controlled, the ammeter kicks like mad when it switches on. Took 20 mins to do 100m leaving a show yesterday in 20+ degrees heat, the fan coming on for about 15 seconds every minute, but it did the job and kept everything cool. I had my arm trailing outside the door and could feel the rush of hot air coming out from under the car when the fan was on. Ralph I also have a large fan which I have on a manual switch under the dash. In summer here it isn't unusual to have 40+ days and the fan keeps the temp under control but running hotter than normal. On Australia Day public holiday (26 Jan) last year we were in a 20km traffic hold up in 45Deg. The temp got up to half way between normal and max but she didn't boil or play up too much (the engine didn't like the heat under the bonnet I suspect). Quote Link to post Share on other sites
MilesA Posted June 1, 2021 Report Share Posted June 1, 2021 Don't forget Roger's excellent compendium of overheating causes and answers. Miles Quote Link to post Share on other sites
RogerH Posted June 1, 2021 Report Share Posted June 1, 2021 This is Menno's (sorely missed from the forum) compendiumnium, I simply formalised it and added a couple of items as did a few other posters. Roger Quote Link to post Share on other sites
Lebro Posted June 1, 2021 Report Share Posted June 1, 2021 My single Revotec fan draws lots of air through the rad, & is more than enough to keep the temperature down to "normal" even on the hottest day staionary after a long blast. Yes, it draws a fair amount of current, but not a problem if you have an alternator fitted. Bob. Quote Link to post Share on other sites
EliTR6 Posted June 1, 2021 Report Share Posted June 1, 2021 4 hours ago, John McCormack said: I also have a large fan which I have on a manual switch under the dash. In summer here it isn't unusual to have 40+ days and the fan keeps the temp under control but running hotter than normal. On Australia Day public holiday (26 Jan) last year we were in a 20km traffic hold up in 45Deg. The temp got up to half way between normal and max but she didn't boil or play up too much (the engine didn't like the heat under the bonnet I suspect). Forget the car, I would melt in those conditions! 24degC here today and I'm keeping the shadows company Manual override is the way to go Quote Link to post Share on other sites
MilesA Posted June 1, 2021 Report Share Posted June 1, 2021 13 hours ago, RogerH said: This is Menno's (sorely missed from the forum) compendiumnium, I simply formalised it and added a couple of items as did a few other posters. Roger I stand corrected Roger, but thanks to you both. And I agree - Menno is sorely missed. Fortunately, the search function shows up a lot of his useful historic contributions. The document provided me with hours of 'fun' when undertaking my own overheating root cause analysis and solutions. If you are in a mind to update it, one additional tip would be to use a high flow thermostat such as the TRIDON Model TT2000-170 as used / recommended by some Australian 4 pot owners. Also, in the absence of finding an original 3A grille with wider openings, crimp the bars on a later version to increase the openings. Miles Quote Link to post Share on other sites
Nigel C Posted June 2, 2021 Report Share Posted June 2, 2021 thanks for the replies, yes they are going the right way. Unfortunately they do have to be in the nose of the car and blow as apposed to suck. There is a good draft from the front of the car so they certainly are sucking the air from outside. They are mounted on a frame supported independently and virtually touch the core of the rad (I don't like cable tie/through rad fixings) all round. With the old fans, when you step out the car whilst they are running you can feel a real strong draft coming from under the sill....not so much with these new ones...which is a disappointment when you think the technology of the previous ones was over 45 years ago! Quote Link to post Share on other sites
John McCormack Posted June 2, 2021 Report Share Posted June 2, 2021 20 hours ago, EliTR6 said: Forget the car, I would melt in those conditions! 24degC here today and I'm keeping the shadows company Manual override is the way to go A few years ago we had a club run to the Temora Aviation Museum (Google it). We then went to a members place in Leeton, about an hour away. It was at least 45 deg (common in summer out there) and a couple of owners new to TRs went topless. The rest had the soft tops on for shade. The couples in the topless cars were severely dehydrated by the time we got to Leeton. Lesson learnt, the cars have tops for rain and for shade. Quote Link to post Share on other sites
BlueTR3A-5EKT Posted June 2, 2021 Report Share Posted June 2, 2021 32 minutes ago, John McCormack said: A few years ago we had a club run to the Temora Aviation Museum (Google it). We then went to a members place in Leeton, about an hour away. It was at least 45 deg (common in summer out there) and a couple of owners new to TRs went topless. The rest had the soft tops on for shade. The couples in the topless cars were severely dehydrated by the time we got to Leeton. Lesson learnt, the cars have tops for rain and for shade. Haaa! Quote Link to post Share on other sites
John McCormack Posted June 2, 2021 Report Share Posted June 2, 2021 (edited) 3 minutes ago, BlueTR3A-5EKT said: Haaa! Excellent idea. A few of our owners have done similar, using shade cloth. Edited June 2, 2021 by John McCormack Quote Link to post Share on other sites
stuart Posted June 2, 2021 Report Share Posted June 2, 2021 5 minutes ago, John McCormack said: Excellent idea. A few of our owners have done similar, using shade cloth. Called a "Bimini top" I believe. Stuart. Quote Link to post Share on other sites
Nigel C Posted June 2, 2021 Report Share Posted June 2, 2021 more like a Bikini, excellent used to have something similar on Land Rovers and I built one for the Willys Quote Link to post Share on other sites
AndyR100 Posted June 3, 2021 Report Share Posted June 3, 2021 This thread has been quite timely for me..... The temp gauge on my 4 has run at just over 1/4 ever since if had it, consequently I never had any overheating thoughts in my mind. couple of weeks ago I had no reading at all on the gauge (car running fine), checking it out I had full deflection on the gauge when connecting the temp sender connection to the block so no issue with gauge or wiring. I got a replacement GTR104 from Chic Doig and all working consistently again - although now I am reading a smidgen over half (185) and I started to have heat-anxiety . This thread has help ease my concern that this is what my gauge should have been displaying all along! Thanks...... Andy Quote Link to post Share on other sites
Nigel C Posted June 3, 2021 Report Share Posted June 3, 2021 ooooooh I can relate to that one..... ignorance is bliss! Have to say I fitted the later gauge and sender but I felt it reacted to slowly and went back the earlier capillary item which give instant heat-anxiety! Quote Link to post Share on other sites
DavidBee Posted July 8, 2021 Report Share Posted July 8, 2021 On 6/1/2021 at 8:25 AM, MilesA said: Don't forget Roger's excellent compendium of overheating causes and answers. Miles Yes, thanks Miles! I followed Roger's advice and installed an overflow bottle ("the tube next to the radiator cap can be routed into the overflow bottle. Special rad cap required."). Question is: what identifies this "special" cap? Or is it simply the cap fitted to TR4 rads which were equipped with overflow? Quote Link to post Share on other sites
Lebro Posted July 8, 2021 Report Share Posted July 8, 2021 The "special" part of it is that it needs to seal around the top as well as on the seat lower down. As supplied there is a metal disk which acts as a spring to hold the cap in place, but it does not seal, so you get no vacuum when the engine cools down to suck the overflowed water back in. the disc needs to be replaced with a rubber seal or similar (I made a leather one for mine). The TR4 ones have the right top seal, but are shorter than TR2-3A ones, so don't reach the lower seat. Bob. Quote Link to post Share on other sites
DavidBee Posted July 8, 2021 Report Share Posted July 8, 2021 Thanks, Bob, I'll have a look tomorrow. Having a sidescreen again after decades is rather like starting again. Not quite, though, the difference being that now I have the luxury of this Forum and its generosity. Quote Link to post Share on other sites
Z320 Posted July 9, 2021 Report Share Posted July 9, 2021 Hi Paul, my TR4A has a overflow bottle but it is always dry because I let enough air in the rad to be compressed by the expanding coolant. This limits the pressure. As I know the TR3 also was without overflow bottle and this should work without problems if you do not overfill the rad and do not try to bleed all air out. If you have been told that, please don't believe it. The air in the rad is no problem for a CARS waterpump. Possibly you have no cooling problem at all. Ciao, Marco Quote Link to post Share on other sites
Lebro Posted July 9, 2021 Report Share Posted July 9, 2021 I have an "open" overflow bottle on my '3, together with the modified rad cap , which seals the top surface. I can fill my rad right to the very top, & that is where the level stays, as any overflow (when pressure exceeds 4 PSI) goes into the bottle, & then gets sucked back into the rad as everything cools down. Bob. Quote Link to post Share on other sites
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