Gretch

For those who have done it, any recommendations on product, protocol?

Imo000

you are only after flushing the rad or the entire system?

Gretch

System. If I am going to just do the rad, I would contract it out. Seemed obvious to me.

hacker-pschorr

I've seen some pretty big "chunks" come out of radiators. Problem is the only way I've seen one flushed out that thoroughly is with the side tanks removed.

Mrmerlin

Gretch what ever you use make sure to flush the system with water after your done and then open the block drains the block seems to hold just about 2 gallons . When your done flushing, fill the system with your favorite coolant about 1.75 gallons then top off with distilled water and add a bottle of water wetter.
Run the car with cap off and the heater on full hot, till the fans come ( this will let the system self bleed all of the air out
Then fit the cap and take it for about a 5 mile drive with the heater on, let the car cool down and top up the coolant as necessary, coolant level should be just above the bottle seam.

Angel84-928

Anyone have pics of the block drains? Been thinking about doing this also.

Brian B

when you drain the block, leave the cap on the expansion tank to slow down the flow or you will take a bath in coolant. Ask me how I know...

Brian B

I drained the system of old coolant, filed with distilled water and radiator flush, ran it until it was hot, drained it after it was cool, filled it with more distilled water and ran that until it was hot, drained it and then filled it with Prestone pre-mixed. All told, it took me the better part of a week to do, since I had to wait for the coolant or water to cool off enough to drain it.

Not a tough job, but a messy one. The coolant from the block pours all over the place, so try to find a big container to catch it. I used one of those plastic under the bed boxes to do mine and I still ended up wet and with coolant all over the place.

Mrmerlin

the block drains are just under the #3 AND #7 exhauat manifold they are 13mm headed bolts

worf928

Get new AL crush rings for your block drains. Use a bit of anti-seize and a torque wrench when re-installing.

And yup, it's messy business.

icsmike

Done it a bunch all my life and always used the same thing. Drain system completely then fill with water and squirt in some cascade liquid. Run till hot, drain fill with warm water or wait until engin has cooled past the scary point and do it again 2-3 times or until chunks are gone and water is clear. Oh, and make sure heater core is opened up and you get it to running temp for a while before you drain.

Tampa 928s

I have drained mine twice since I found what seems to be some HondaBond in the coolant. I'm not sure how it got in but maybe the intake rebuild. The first batch left a film on the bottom of the bucket. I need to do this a few more times its getting clearer after each flush.
So you used dish washer soap?

icsmike

Yep.

Mrmerlin

honda bond might have come from either the water bridge or the rear block off plate (rear of cylinder haed) or the heater hose plate. or the water pump