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Simon TR4a
Jedi Knight
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Wow, only 500 miles on a rebuilt engine and you are doing 70mph- in a Herald?
Maybe you are pushing it a bit hard..
Simon.
Maybe you are pushing it a bit hard..
Simon.
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Overheating at high speeds
- Thread starter 70herald
- Start date
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Simon TR4a said:
Uhm you might be right, about the 70mph, that was only a small portion of the drive though. Anything less and I will get run down by other drivers around here. That actually was less than WOT. BTW, if I had a different ratio in the differential, it could do a fair bit more at least on level ground. These cars are WAY under geared.
I let up a bit on the gas pedal this morning and it was a somewhat better.
Of course I also did a few other things:
Replaced the thermostat, it worked perfectly well (tested in a cup of hot water) but it was French. I put in a lower temp unit, but once the engine is hot it shouldn't make a difference. Maybe my LBC just doesn't like French parts.
Took apart the water pump. No damage inside, but there is a big gap between the rotor and the housing. I also noticed that the gasket was very thick ~0.8mm. I took out the gasket and sealed it with permatex. This brings the rotor to ~1.2mm from the housing. I think that this might still be a bit to loose, however there there is a good flow of water in the radiator when I rev the engine.
Cleaned the cooling system with "Gunk" radiator cleaner. Basically just TSP and I doubt it made any difference.
Replaced the lower rad hose with a proper Triumph bit. Instead of one I cut to fit from a longer hose. This shouldn't make any difference since the hose was in good shape, but I had it and everything was all apart.
Now, other than continuing to let it break in, I may well be at the limit of the radiators cooling ability. These cars always had a bad reputation around here in high temperatures. The best solution may well be a big Al radiator. Looking through the Summit catalog, it seems that a standard Chevy rad would be very easy to fit, (space requirements, inlet / outlet location) and they are quite reasonably priced at least relative to a custom rad.
Depends which direction. Heading west, I would need pontoons in under 45 minutes. North / South I can go somewhat further, and there is a fairly new main road heading N/S where 70mph is the limit, however speeds are closer to 85-90mph.angelfj said:Please induldge my curiosity. At 70 mph don't you run out of country very quickly?