coolant flush (1 Viewer)

[fishwater]

i'm in the process of replacing my coolant and plan on back flushing the heater/core, flushing the block and of course the radiator. i've read the FAQ and researched the posts, but i'm curious:

1) what would be the best way to back fill the block (and heater?) after the flush? i read to fill the block via the upper radiator hose, but what is the best way to do this to keep an air pocket out and if i do it this way:

2) what is the best way to tell the block is full? pour in fluid from the upper radiator hose until it comes out of the heater inlet? (doesn't seem like there'd be enough pressure pouring fluid from the upper radiator hose to push fluid up to the inlet unless you attached a a longer hose.)

3) also, what is the best way to flush the block? does anyone back flush it with the Tee in the heater inlet with flow going to the block? or is this necessary? or detrimental?

 

[Grench]

Opinions may differ. I'll give you mine.

i'm in the process of replacing my coolant and plan on back flushing the heater/core, flushing the block and of course the radiator. i've read the FAQ and researched the posts, but i'm curious:

You may be overanalyzing this. I know I did. I did 5 tap water flushes and 3 distilled flushes before I felt like it was clean enough to fill/finish.

1) what would be the best way to back fill the block (and heater?) after the flush? i read to fill the block via the upper radiator hose, but what is the best way to do this to keep an air pocket out and if i do it this way:

Garden hose pointed into the top radiator hose for the water flushes.
Cut the bottom off of a distilled water jug. Flip it over and it becomes a funnel with a spout that fits perfectly into the upper radiator hose. Once thats full, connect the hose and fill the radiator through the cap hole.

2) what is the best way to tell the block is full? pour in fluid from the upper radiator hose until it comes out of the heater inlet? (doesn't seem like there'd be enough pressure pouring fluid from the upper radiator hose to push fluid up to the inlet unless you attached a a longer hose.)

The top radiator hose dumps right into the block. Fluids by definition move to the lowest potential energy state. I.e. $@%^ flows downhill. By filling from the top hose and then from the radiator cap, you've filled both sides of the system from the perspective of the thermostat. You did buy a new thermostat, right? Did you install it with the little valve thingy the right way? (I didn't the first time and re-did it on suggestions in the FAQ.)

3) also, what is the best way to flush the block? does anyone back flush it with the Tee in the heater inlet with flow going to the block? or is this necessary? or detrimental?

Remove the radiator cap, pull the plug on the block. There is enough water stack pressure to have it hit you standing in the wheel well. I think it is enough to push out the congregated stuff at the bottom of the water jacket.

YMMV.

Quick thing on having one of these in the air... You'll have to in order to get to the block drain plug. Always chock both sides of the rear wheels when you put one of these trucks up on jack stands in the front. Even one wheel. Never rely on the parking brake. "Park" means -nothing- with one wheel off the ground.

 

[CJF]

3) does anyone back flush it with the Tee in the heater inlet with flow going to the block? or is this necessary? or detrimental?

I do this, mainly because the tee was already there when I bought the vehicle. You need to be careful with the water pressure if you go this route. (For example, my household pressure is at or above 60psi.)

Curtis