New cars get old too and needs these same things replaced. Will still cost less to fix his car than buying a new one and be in debt again...
That is why you don't keep cars when they get to this age.
Put it this way - what you should be looking at when working out how much a car costs is the usage cost.
Usage cost can be calculated as follows:
Purchase Price + Maintenance Costs + Fuel Costs + Insurance Costs + Breakdown costs (if any) - Resale Price
Divide by the number of months that you have owned the car to get a per month figure, which might be more useful. Including fuel and insurance is optional - I do so because some cars are cheaper to run in terms of fuel and insurance and others.
What this means is that when calculating the actual cost of a new car, the resale price needs to be factored in, which most people don't do. They just look at the monthly installments and think that is the true monthly cost. It is not. If the OP pays R36k to repair this car, he has essentially made 12 payments on a new car, in one go. However, in his case, spending R36k is not going to raise his resale price by R36k. With a newer car, spending R36k on installments will probably mean you could get R20k back in resale value. And remember, with a newer car, maintenance costs are typically R0 or near R0, depending on warranty etc.
After spending horrendous amounts of money on maintaining my old car, the 1994 Merc, I will never again keep a car out of warranty or maintenance plan. It is not worth it. Every single cent you spend on maintenance is literally flushed down the drain.
In fact, lets use me as an example. In April, we had a Kruger Park trip. So, in March, I took my car to the garage, a mechanic that I trust, to make sure that everything is okay. Long story short, the following needed to be replaced:
Alternator
Starter Motor
Battery
Radiator
Viscous fan coupling
Two new tires
Total cost was somewhere around R20k. So I think to myself, I've just spent all of this money on this car, lets keep it for a few months to spread that investment out over a longer period of time. 2 months later, the car overheats on a long trip and the engine is damaged. I had to sell the car for R15k when I could have probably got R35k had it not overheated.
And this was a very well maintained car. I spared no expense on it, I bought it for R40k and spent over R80k fixing it up, all told. I had it regularly serviced by a professional. The problem is with an old car, is that you think spending money on fixing it up will prevent further problems from appearing. It won't. No matter what you do, when a car gets old and starts giving problems, it will only give more problems, not less. You cannot rescue it. It will just get worse, and one day you will be stranded on the highway. And all of that money that you spent will be lost.
That R20k that I spent? Gone. Complete waste. Same could happen to the OP - he could spend this money and then have a car accident 2 months later. Insurance will pay out the retail value at most of his car, which will not include what he has just spent.