Coolant Replaecment

[Bruce]

What is the best way of flushing the cooling system? I want to get rid of all the old coolant, so where is the best place to drop the coolant out from?
Is it a good idea to use a flushing agent as well?
Cheers Bruce

[geeves]

By flushing agent I assume you mean one of those radiator cleaning liquids. Unless your radiator has been neglected and now has more rust than water or you have overheating issues I wouldnt bother.
The system can be a pain to bleed if you empty it so as long as you have a good water suply this is the way I would do it. (It uses 10 times as much water as other ways but is quicker and you dont have to bleed the system afterwards)
With a cold engine remove the top radiator hose then remove the thermostat housing and thermostat. Place the garden hose in the top of the radiator and turn on. Run untill the water runs clear out of the thermostat housing then anouther 5 min or so. If the hose builds up presure in the radiator instead of flowing freely through the engine get the radiator profesionaly cleaned. Refit the thermostat and hoses etc and pour the measured amount of antifreeze concentrate into the radiator remembering your system is already 2/3 full of water. For corosion protection you need 20% antifreeze but if you go into areas that get good frosts this should be increased up to 50% Run the engine for 10 min or so to remove any air before refitting the radiator cap topping up as nesecsary Refit the cap and check for leaks. Go for a 20 min drive let cool and recheck level
easy

[Bruce]

Thanks Geeves, I just usually drop the botttom hose andf hope it all comes out there, ok will do it this way, do I need to do gasket on thermostat housing? (notm looking at the motor at the moment)
Cheers Bruce

[geeves]

Its a strong gasket so should survive ok Mine did. Some models use an oring

[Bruce]

Thanks again, it s the Wizard Iam having the problem with, when Iam going up a steep climb and giving it to her the temp starts to rise. Its an auto (just had the trans serviced, it is going a lot better) So Iam hoping it the coolant or thermostat. Anyway will service the rad and see what happens.
Cheers Bruce

[justin]

Hmm this is a familiar sounding story, hopefully a flush through will solve your problems. The gasket is pretty robust, but you can get a newy from Repco as I did + the thermostat which turned out to be the same as a rodeo 2.8, (not the Jackeroo 3.1?). Be aware that the flush can also loosen crap which is sealing old coolant hoses, (as I discovered), so keep an eye out for leaks. If that doesn't work get the rad tested for heat spots as that is normally a fault of inefficient cooling. J

[Bruce]

Hi JUstin, thanks for your advise to.
Had a look at the header tank and it looks pretty crappy, so hoping its just needs a good flushing, but will check out the thermostat as well.
My biggest worry would be when Iam towing the camper trailer up some monster hill.
Cheers Bruce

[geeves]

Also check for mud in the fins This can only be cleaned thougherly with the radiator out and will only be a problem if you play in the mud

[Witchdoctor]

I'v got a rad that will help ;D