Antifreeze does wear out eventually but the partial changes will get the
most of it. For the little left, I really wouldn't worry.

My reasoning is I have almost 'never' seen any garage actually open the
drains in the engine block when they do a so called flush and fill.

This leaves a mess of fluid in the block each time.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's

Mikail wrote:
>
> Thanks, Al, Mike & John,
> John, the rad does not have its own header tank or cap. Its like a long
> honeycomb tucked well behind the front grill, about 2 feet wide and
> about 9 inches deep. and both inlet and outlet hoses are at one end.
> Unfortunately the end which is totally covered by the air filter and
> other assorted pipework EGR pipes ect,running down to the turbo
> intercooler.
> No access at all from the top of the engine bay , cannot even get one
> finger to the bottom hose from above.
> The rad is not down at the bottom of the front grill space, its
> relatively high up With the turbo intercooler radiator below it.
> In days gone by, more simple cars, I used to pull the bottom hose when
> the rad was lower, with a hot engine, thermostat open and most of the
> coolant came right out.
>
> Al, the 1.5 litres is part of the 6. Interested that you consider the
> remaining old fluid not critical. I had hoped someone would comment on
> this.
> Its all ( well mostly) fresh coolant right now so I wondered if a
> regular partial change plan running from now would be ok.
> On the plus side I thought the cooling system would be getting a
> regular infusion of fresh ethylene glycol. I dont know what happens to
> the dwindling molecules of the old coolant and additive though. Like,
> does it turn into acid or something?
> Mike, Good idea re the tester, I will get one.
> Maybe I am spending for too much time thinking about antifreeze but
> it was a grueling experience doing our 2 cars the other day.
> Thanks everyone for commenting on this,