Sounds fine to me…
as the fluid warms up viscosity will go down. The job of the clutch is to limit fan speed until the bimetallic spring at the front of the clutch expands and locks the clutch which will only happen when the radiator is seriously hot and then the fan is quite loud.
When started cold, do you immediately have pressure on the coolant hoses?
With the ac on full power on a warm day and slow, hilly terrain it should be alright if it gets a little warmer than usual. The electric fan will kick in at an indicated 95° on mine.
It was out technically 500 miles ago but that was 3 or 4 years ago way before we go the car running and driving and we were painting the engine bay. I don’t recall doing anything other thank a quick flush of the radiator with a hose. it may very well be clogged with dirt and I completely missed it.
don’t know about SIII cars, but SII radiators have beautiful drain plugs at the lower radiator hose and a kind of tap accessible from top. The flushing operation is nicely described in the ROM.
With your symptoms, your location and your driving habits I’d try everything possible to get the original setup in best possible working conditions. Get some radiator cleaner, flush the radiator while it’s still in the car, rec-check it for tightness, then take it out to proceed from the outside and make room to tackle the clutch. My viscous couplings have always been much tighter, by the way, with fan stopping close to immediately when cold and hardly discernibly longer when warmed up.
I wouldn’t go for another radiator, but - if the radiator should leak - think about recoring. About 250 EUR in this part of the world, but a correct radiator with as new or better performance.
Thanks for the suggestions! I think I am going to leave my fan clutch alone for now as it seems to be still working well enough. It’s not perfect but I think my main issue lies with the radiator, I had already started flushing the radiator with your generic flush stuff. I have enough to do it a couple times. the one round that I already did yielded some VERY muddy coolant that was new only a few months ago and when left to sit overnight a LOT of sediment i.e. rust and deposits showed up at the bottom of the fluid tray. I am going to flush it until it comes out clean with very little or no sediment and see what that does. If it solves it then happy days, if not then I will try to remove the radiator and see what is up and possibly replace/recore it. btw are you able to recore plastic end tanked radiators? the series 3 has plastic end tanks rather than copper.
Indeed. Fresh coolant should remain clear a bit longer than just one night! Following this route sounds promising enough. Do a couple of more cleaning rounds. Generic off-the-shelf cleaners should not be overly aggressive either so it’s just your time well spent.
I just went to check as it looked very original and it seems that the end tanks are in fact not plastic. I am not sure why I assumed they were but they are not.
Kirbert
(Author of the Book, former owner of an '83 XJ-S H.E.)
39
If the radiator doesn’t leak, think about boiling. It’s not really boiling, it’s a process the radiator shops do where they dunk the whole thing into some chemical vat that makes it bubble and cleans all the crud out. Then it leaks! But it’s a pretty cheap process IIRC.
Ok, good to know. I would prefer to keep the original both for looks and it feels good to fix something rather then just chucking a 35+year-old original part away if I can help it.