Engine/Transmission (1998.5 - 2002) Coolant flush

[Stranger]

I'm going to flush/replace the coolant in my '02. I think I want to back flush the heater core. Looking at the firewall from the front, which coolant line is input to the core?
Also, how do I completely drain the block as there is no drain?
Thanks in advance.

 

[Cummins12V98]

I just blast it both ways with a garden hose.

 

[Stranger]

I just blast it both ways with a garden hose.

That's what I was thinking. Just wanted to get another opinion. Thanks.
Now, on to draining the block. Any ideas?

 

[NIsaacs]

That's what I was thinking. Just wanted to get another opinion. Thanks.
Now, on to draining the block. Any ideas?

The line coming from the head is the direction of flow. By design, the block will mostly drain. If you put the rear tires on blocks, it will help level the block. If you have compressed air, you can blow most of the coolant out by using the fitting at the head for the heater core. I would also blow air in the top of the radiator at the inlet. With crossflow radiators, coolant will "pool" in the cores. I also recommend you syphon the coolant out the top, at the radiator cap, no mess. I use about 6-7 feet of 3/8's fuel line, the longer the better, less chance of getting a mouth full

If there is any doubt about how clean the heater core is, you might use some Toilet bowl cleaner, (the works) With a small funnel, fill it up and let it set for about 30 minutes. Both heater hoses will need to be above the level of the core. Be careful here, the cleaner is toxic/acidic.

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[Stranger]

The line coming from the head is the direction of flow. By design, the block will mostly drain. If you put the rear tires on blocks, it will help level the block. If you have compressed air, you can blow most of the coolant out by using the fitting at the head for the heater core. I would also blow air in the top of the radiator at the inlet. With crossflow radiators, coolant will "pool" in the cores. I also recommend you syphon the coolant out the top, at the radiator cap, no mess. I use about 6-7 feet of 3/8's fuel line, the longer the better, less chance of getting a mouth full

If there is any doubt about how clean the heater core is, you might use some Toilet bowl cleaner, (the works) With a small funnel, fill it up and let it set for about 30 minutes. Both heater hoses will need to be above the level of the core. Be careful here, the cleaner is toxic/acidic.

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Thanks NIsaacs, that's the info I was seeking.