Never a dull day! I was a little concerned that the rad fan decided to come on with low temperature, and continue after ignition off, after yesterday's snowy tracks. A quick check of the otterswitch wiring (relay loop) revealed some damaged sheathing. As I tried to wiggle the connectors off, the ba*#@¿d rubber seal of the push fit thermoswitch split, steam cleaning the crosshead and nearly boiling my knuckles! Fortunately plenty of snow about to plunge my fist into!
Radiator removed today, and at the rad shop for fitting a threaded insert. Hopefully serve as a note of caution to those with older trads; I suspect the sealing rubber sealing on mine was factory original- 20 yr old rubber perishes!!

Never trusted the fitting on my 79 +8 ,rigged up a couple of cable ties to secure it.

This one had a metal spring affair. To be honest, it would have been entirely sensible to have waited for everything to cool down before investigating , but far less dramatic!

Glad you weren't hurt & that it is fixed

Thanks John, I did sustain stupidity blisters, but I self patched and got on with it. The rads at the fabricators, their man's not in until tomorrow, so a few more days yet. Typical that this would happen two days before the MOT booking.

Sorry to read of your rad fan stat issues. I never liked the look of that set up, and coincidentally my otter switch failed a few months back, I fitted a new rubber grommet when I replaced it. From a dull memory the rad fan runs until the stat determines the engine has cooled to the required temp even after the ign is switched off on my mid 80`s +8.

Fitting a stat over ride switch is a popular mod for those with otter switch anxiety..

Fitting a threaded insert to the rad seems an improvement, though it might be worth paying attention to the temps at which the new sensor switches relative to your engine`s ideal operating temp. I think my +8 runs cooler than the later lean burn engines..?

Grommet, that's the word I was searching for, thanks Luddite 😊 I've read a fair bit on it, and decided to go for the threaded conversion. I think it widens up the options too as far as future replacements go. I think my bottom fitting was rated on at 99degrees c, at least it never came on below 100 on the temp gauge although I'm aware that's not necessarily accurate. If I put a 15mm threaded bung in, I can experiment with on temperatures. Never had a problem with overheating per say, as the fan always kicked in between 100 and 105 on the guage. If anything, I've always thought it runs a bit on the cool side. I've set up the override switch, and am happy with that function for backup. Just need to splice in some fresher cable for the relay loop now.

The threaded bungs I weld into my radiators have an M22x1.5 thread
This opens up a huge variety of fan switches and temperatures

I fit them in the top tank in most cases, and supply a 98/93 thermoswitch in with the radiator kit
I prefer the fan switch to see the highest temperature- IE when the coolant leaves the engine rather than the lower temperature coolant after it’s passed through the radiator
If I fit the bung in the bottom tank I supply a lower switching thermoswitch (93/88 from memory)

Wouldn’t this be the time to off set the costs and invest in a new aluminium radiator, I believe they are more efficient and less chance of overheating ?

I’m very pleased with my SiFab one, looks good to

Seems like my rad may be original and has served well while touring in Italy a few years back in the hottest June temps recorded in the region when the locals were fainting in the streets. That my old Morgan`s engine is original spec and not been subjected to mods in search of power, thus the OE rad may not be as taxed as some..?

Seems our normal engine running temps are similar Treesurveyor. How could you forget the name of Wallace`s dog...