corrosion inhibitor

[shergar]

hello all , i have a ford service bulletin from 1986 about corrosion inhibitor for 3 and 4 cylinder tractors , i believe my 4000 has a 4110 engine ? and early this year when checking coolant level found that the water had gone a rusty colour , it took an age to flush the system , using normal anti freeze at the moment 50/50 but should i be using these inhibitors as well or am i worrying about nothing , numbers on the engine *d520057* 4m15 83982462 also what is the best grade of oil to use in this engine , using super universal 15/30 at the moment .

thanks wayne

[russelm]

Modern antifreeze has the inhibitor already present in the mix (described in BS 6580 which is now on a 2010 revision)

Beware, for most glycol based antifreze, the inhibitors only last around 2 years hence why it needs regular changes