3FE - question on cooling system flush (1 Viewer)

[LC8pilot]

Greetings - Can somebody point me in the direction of the procedure to back flush the cooling system on a 3FE? I'm not sure which hoses are which. FWIW - I do have the Prestone flush kit lying around here somewhere. Is it necessary? Also, what is the proper mix ratio of 'red' to distilled water? The FSM only says to 'mix it'.

 

[KLF]

I'm not a big fan of the Prestone kits, after I had one of those T fittings develop a slow leak and I suddenly overheated one hot day. I would just use that flush fluid, mixed as recommended, take it for a drive to get up to full operating temp. Then dump and flush with plain water. Then fill with 50/50 mix of the red stuff.

Don't forget to drain the block. The drain plug is on the driver's side, near the rear, kinda under the intake fan sensor.

 

[91 4runner]

x2 on the prestone "T" the plastic cap heats up and deforms and tends to leak, go to a trusted shop and have them do the flush, it shouldn't be more then $70.00

the theory behind it is that you hook up two lines from a flushing machine ,
one which pressurized coolant comes out, and the other witch provides a vacuum to remove old coolant.

the pressurized line from the flush machine must be hooked up in such a way that it can "off set" the spring in the termostat so that coolant me flow the opposite direction or "back" hence the name back flush,

its simpler to take it to a shop with a flushing machine


and as far as the red coolant, a 50/50 mix of red and distilled water is what is needed
you can change the ratio if you live in extreme climates, but for the 99.99% of us 50/50 is the norm

 

[LC8pilot]

Ok, cool. Thanks for the input. Will forget about the Prestone kit.