Coolant Refill After Alternator Install

[BWolfe]

I have a question regarding the best practice for replacing some of the coolant in my 2000 LC.

Background:
Replaced my alternator with an OEM reman from Toyota. I really appreciate everyone's knowledge on this forum as I had multiple references for this work.

For me, it was much easier to remove the PS pump and the radiator hose #2 to get the alternator out from the top. The amount of room that opens up is 1000% worth the small amount of effort it takes to remove the pump IMO.

When I removed the radiator hose, I caught the coolant in a non-measured bucket (wasn't planning on doing this initially, still no excuse for not have what you need). It mostly came out of the bottom of the radiator, but eventually some came out of the engine as well. It's probably about 2 gallons worth, and I'll grab a measured container tomorrow to know for sure.

Since I have to discard what came out, do I a full coolant flush or can I just replace the amount I lost? The coolant is in good condition so I'm ok with keeping what's still inside if that's ok. I've got the FSM open to the coolant replacement page and have some videos so I feel fine doing whatever needs to be done. TIA

 

[OrionZodiac]

Just replace what you lost. I forget the exact procedure, but you want to pour new coolant in the radiator and reserve tank. Turn on car, set heater to max, and let idle. When the thermostat opens, coolant will drain from the reserve tank/radiator into engine. Top it off once engine cools. If you go for a drive, check coolant level after. Also check coolant level the next day; I feel like the level goes down once things settle overnight. Whatever you do, don’t open radiator when engine is hot. It is pressurized and can spray/burn you

 

[BWolfe]

Just replace what you lost. I forget the exact procedure, but you want to pour new coolant in the radiator and reserve tank. Turn on car, set heater to max, and let idle. When the thermostat opens, coolant will drain from the reserve tank/radiator into engine. Top it off once engine cools. If you go for a drive, check coolant level after. Also check coolant level the next day; I feel like the level goes down once things settle overnight. Whatever you do, don’t open radiator when engine is hot. It is pressurized and can spray/burn you

Thank you. Your thorough answer is extremely helpful.

 

[Super77]

Coolant is toxic and requires careful disposal. When I remove some from the system for service and I know it still has some life left, I just filter it through a white cotton t-shirt and pour it back in the radiator. I’d rather deal with disposing that soaked shirt than a gallon or two.

Replacing coolant requires “burping” the system. Eventually the air bubbles you may have introduced by partially draining will escape, but you may see some temp gauge fluctuation and have to top up the overflow tank. Idling while parked uphill helps, but the fastest hack is a burping funnel, which temporarily overfills the radiator so that escaping air is immediately replaced by coolant in the funnel.

 

[Patassa]

Park on a hill with the radiator at the highest point, squeeze the upper radiator hose several times with a funnel holding a liquid level in it just above the top of the radiator, while you are idling and all heaters set to max heat and blower on high. I've never had issues getting all the air bubbles out doing this way.

 

[David310]

I use this mentioned previously. Just fill the funnel with coolant, turn on vehicle, turn on heat front and rear, let come up to temp. I like to squeeze to radiator hose a few times before turning vehicle off.

 

[BWolfe]

Coolant is toxic and requires careful disposal. When I remove some from the system for service and I know it still has some life left, I just filter it through a white cotton t-shirt and pour it back in the radiator. I’d rather deal with disposing that soaked shirt than a gallon or two.

Replacing coolant requires “burping” the system. Eventually the air bubbles you may have introduced by partially draining will escape, but you may see some temp gauge fluctuation and have to top up the overflow tank. Idling while parked uphill helps, but the fastest hack is a burping funnel, which temporarily overfills the radiator so that escaping air is immediately replaced by coolant in the funnel.

Thank you. I’ve left the coolant uncovered for a couple of days- you think it will be ok to add it back as long as I filter it?

 

[BWolfe]

Coolant is toxic and requires careful disposal. When I remove some from the system for service and I know it still has some life left, I just filter it through a white cotton t-shirt and pour it back in the radiator. I’d rather deal with disposing that soaked shirt than a gallon or two.

Replacing coolant requires “burping” the system. Eventually the air bubbles you may have introduced by partially draining will escape, but you may see some temp gauge fluctuation and have to top up the overflow tank. Idling while parked uphill helps, but the fastest hack is a burping funnel, which temporarily overfills the radiator so that escaping air is immediately replaced by coolant in the funnel.

Thank you. I filtered it and will resuse. Bought a gallon to account for spillage.

 

[Jack90210]

FWIW, the coolant will pass through the heater cores whether or not the controls are set to "heat."

Fill the system with the vehicle facing uphill and you'll have much less burping to do.