Hi all . Changing my stock radiator to a mishimoto at the weekend. When I replace the coolant does the system need to be completley empty or can I just fill the rad and header tanks back up? Im not sure what coolant it has in it at the minute so I might be mixing the brands. Is that bad?

 

Mixing brands is not good, for the cost of it which is not much and to prevent air locks its best just draining the lot, you will lose the lot anyway with a rad change.

 

Will it drain out of all the pipes and heater matrix then ?

 

yeh as the lower pipe on the rad is the lowest point so you will lose the lot, turn your heater to full, once fitted refill with a decent brand antifreeze/coolant at 50/50 and fill system very slowly squeezing the top and bottom rad pipe to "burp" air from the system.

ive not long fitted a mishimoto to mine, its a very good quality rad

 

Ahhh cool. Did you fill it from the tank near the turbo?

 

Fill from the header (near turbo), remove the cap on the rad (if it has one) until it you see it start to come to the top then replace and carry on filling the header to the brim, then fill the expansion tank to half way.
when filling though do it very slowly as there easy to air lock.

 

Sounds easy enough . Thanks for that