Coolant Flush
 

I have an 88 iroc base with a 305 TBI engine. The car has been sitting for several years and I need to drain all fluids and replace them, but I am not sure as to how to perform the radiator flush. What hoses am I to remove and what liquid do I use to do the flush? Should I use water or buy a special radiator flush liquid? Please help! Thanks!

Re: Coolant Flush
 

my f-body was sitting for about 2-1/2 years, but i ran her atleast once a month for 30mins or so to operating temperature, but still just recently flushed all fluids. Coolant is the easiest. What i do is drain by the lower radiator hose, the one connected from water pump to radiator inlet on the passenger bottom side. Its held on by a hose clamp all you need is one tool; flat head screw driver. You dont even need to get your car on ramps :lmao: Just unscrew the clamp it will start to leak but you need to pull it all the way off the radiator to allow it to drain. Tighten her back up after shes done draining and fill with your choice of coolant. I use Peak 50/50 longlife antifreeze. But dont get fooled by the "longlife" printed on the jug.

FYI this does NOT get all of your coolant out of your motor, but is the most common procedure for a coolant flush on these engines.

Re: Coolant Flush
 

Easiest way to get ALL the fluid out (and by ALL I mean EVERY LAST DROP) is to remove the block drain plugs, in addition to draining the radiator. The pass side one is cleverly disguised as the knock sensor. Once you find that, the driver's side one is in the exact same place, except (duh) on the other side.

I don't use the 50/50 anti-freeze; not because there's anything wrong with it, but rather, because 100% AF is like $12 a gallon, but the 50/50 is like $11 a gallon, meaning you're paying $5.50 for a half-gallon of water. I'm pretty dumb and all that, but I'd like to think that I'm smart enough not to fall for that one. Instead I buy the 100% stuff, and then go over to the "water" aisle in the store and spend $0.79 a gallon for distilled water. I NEVER EVER EVER FOR ANY REASON EXCEPT EXTREEEEEEM DESPERATION (sitting by the side of the highway with a burst part) put tap water in my cooling system; distilled water ONLY.

If the car still has AF in it now, prolly doesn't really need a "flush"; just renewing the fluid should be fine. Only needs a "flush" if you see foreign matter of some sort in there. Corrosion, scale buildup, oily gunk, or stuff like that. Otherwise, new coolant will fix it right up.

Re: Coolant Flush
 

holy **** i never noticed that i am buying a really overpriced half gallon of water!! Thats a pretty smart idea right there!!

Re: Coolant Flush
 

I'm with Sofa, I don't buy the 50/50 stuff. Straight antifreeze and distilled water.
I try and pull the block drains if i can to drain all of it. I usually try and pull the heater hoses off and flush that out with a garden hose also.
If you only drain the rad your probably only changing 2/3 of the coolant at best.

Re: Coolant Flush
 

Chocolate Milk. This is with an old Prestone Flush Kit I have had for a few decades.

Re: Coolant Flush
 

I get my 50-50 coolant at fleet farm $6 a gallon so your not even paying for water and you can just dump it right in.