I’d like to do a full coolant flush of my 2008 GH1 Mazda6. I have sourced the correct P-OAT coolant that is free of silicates, nitrites, borates and amines. I intend to flush and reverse flush radiator and engine block using radiator hoses and garden hose as shown in Scotty's flush video. But I also want to flush the heater core/matrix.
The inlet and outlet hoses on the heater core are quite far back in the engine well, up against the firewall and its quite difficult to access the clamps. I was hoping to attach some 5/8 vinyl aquarium hoses to them to flush out the heater core/matrix. Then once the system is clean, using the vinyl hoses, top up the heater core with 50/50. Then fill the rest of the system.
Does anyone have any advice on flushing the heater core in light of the difficult to access inlet/outlet hoses. Also, can explain how I identify which is the inlet and outlet? I’ve seen Scotty recommend removing the thermostat so you get an uninhibited flow while circulating the fluid before changing. However, it appears that the thermostat on this Mazda 6 is integrated into the housing as a single replaceable unit and therefor I can’t just remove the thermostat and replace the housing. Any ideas?
Thanks.
Yes because of your design. Seeing that it's such a pain in the butt, if I were you I would just pay a mechanic to do the job. Good mechanics have a flushing machine that uses heated coolant. It's just hooked up to the car and it will flush the whole system out and you don't have to take anything out. It will do it because it's heated and the thermostat will remain open during the process
@scottykilmer Thank you Scotty for taking time to reply. I was just watching your live stream at 1:30AM in Aus. The problem is I have purchased coolant already and my local mechanics won't accept customer sourced parts due to inability to guaruntee them and for liability. Also the coolant was actually quite hard to source. I could only find 2 products here in Aus that fit the service manual specs and Mazda factory FL22. I.e. P-OAT coolant (phosphate activated with no silicate, borate, nitrate and amines). The mechanic was just going to use some generic coolant with Silicates. Could I achieve similar results by simply repeating flushes of distilled water and finally radiator flush cleaner. Driving around in between flushes to get the car up to working temp/ heat on full (not sure if i need fan on) and the thermostat open? I dont mind taking time to get it right. Its just the process I'm not overly familiar with. The coolant doeesnt look too bad actually. It seems fairly clean. The car is 2008. I have to assume it's never been changed lookng at the service history, but the car only has 67000 miles on it. I can still flush and reverse flush the radiator. I am going to try my best to get at the heater core hoses, but not optomistic. Is there a way I can still flush the engine block with my integrated thermostat/housing.? Should i remove the whole thing? I've never attempted this before and it gets a little confusing where to insert the garden hose into what coolant hoses and which to unplug and connect. Can you please break ot down like you are speaking to a moron and offer any possible work around for me to do the flush myself besides paying a mechanic. Thank you Scotty. Love your work and your content.