Heater Core Bypass Process

So I have the dreaded antifreeze smell in the car through the vents. Luckily, no antifreeze on rug inside car just through firewall weep hole under heater core hoses. I picked up a molded U shaped heater hose that's 5/8s on one end and 3/4 on the other. Had to cut the old hoses from the heater core (I'm sure they are original). I have not pulled the hoses from the metal tubes on top of the intake yet.

So here's my dilemma:

I drained about half the radiator through the petcock at the bottom of the radiator. I would assume the fluid level in the motor would drain at the same rate as the radiator (at least that's how it would seem to work in my mind). The coolant level is in the radiator is clearly lower than the upper intake lines. I went to point the small heater core hoses at the back of the engine down to make sure when I pull the hoses off that antifreeze doesn't pour out the tubes. When I did this antifreeze came out surprisingly.

- Why is there still antifreeze that far up the engine when I already dumped a decent amount out of the radiator (probable a gallon)?

- How do I get the antifreeze level low enough as to not get soaked replacing the heater lines with my U loop?

- What is the best way to replace the antifreeze I drained? Is there a trick to doing this? Normally I would fill through the radiator, but I also don't want to damage the motor if the level in the motor is too low. I plan to do a flush in the Spring, but want to put the old stuff back in for now.

Thanks in advance

96pushrod said:

This. If there’s Low antifreeze in the block on startup it will circulate thru when the thermostat opens. You could also pull off the upper radiator hose and pour coolant into the block that way. If I drain a block, that’s what I do before startup

Burping a 5.0 is about the easiest process known to man.

I had a fox I bypassed the heater core on, so what if a little antifreeze comes out. Wear a pair of gloves if it concerns you.

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Thanks! Not worried aobut getting antifreeze on my hands, more about it pouring down the back of my engine and on the trans, exhaust and floor. Seems to be an endless flow just by pointing the hoses down toward the ground.

KZGUNS said:

You can try to raise the rear of the car but you'll likely still get coolant. wont be that much. just top off your coolant and run the engine till the stat opens, you may have to squeeze the upper hose a few times to burp any air out then recheck. Watch your temp gauge and you'll know if it needs burped because your temp will rise. recheck and top off and fill reservoir to appropriate level.

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Good idea. I didn't think to jack up the rear and slosh the antifreeze to the front of the block.