The OP did a compression test and it came out excellent at 190-200.
Maybe the alternator belt, alternator output, and battery should be tested.
Thatās a very good point George about the fan draining the battery. Iāll purchase a new fan switch, sort out the water leak and check the alternator is charging the battery.
The Alfa has an oil temp gauge only, so I thought it may be faulty. But with all the symptoms, I donāt think the car even overheated. Phew!
Quite a big job fitting a new water pump and timing belt, so Iāll get back to you in a few days with some more problems.
Thank you all for your help
Iāve replaced the radiator fan switch on my Corolla twice now. Itās a common failure item for some reason.
A bit of advice if youāll allow. If you are doing a timing belt job for the first time, be aware that if you manually move either crank sprocket or the cam sprocket(s) with the timing belt remove it is possible to damage the valves and the pistons. Not what you want. Take some photos of how the timing marks line up before removing the original belt, and donāt allow the sprockets to move while the belt is off, except minor amounts to set the timing marks on the install. Do this with the spark plugs removed so youāll notice if something is interfering inside the engine. Make sure you fully understand how to set the timing marks before beginning this job by reading the procedure all the way through.
Thanks for the advice. I plan on marking up every cog with tip-ex so to ensure none of them have moved when I fit the new belt. Do I need to check the alignment of everything? Or, if none of the cogs move without the belt in place, can I just assume all is well?
As a general rule, check and recheck everything. As my dad taught me with carpentry, measure twice, cut once.
Well, you need to check everything that is supposed to be aligned, is aligned. Itās not sufficient to simply try to not move the cogs while you install the new belts and call that good enough, b/c it if very easy to move them slightly in the install process and not realize it. The procedure usually calls for installing the timing belt, verifying the timing marks line up, then manually rotating the engine 3 or 4 times, and checking the timing marks again. If they remain aligned, you are good to go. Itās not overly complicated. If you can dial the combination of a lock, you can align the timing marks. The biggest problem folks seem to have is when they donāt understand how and under what conditions the marks are supposed to line up, or they confuse one mark with another.