Trouble adding coolant/water to empty cooling system 3800

[slacktide_bitog]

I'm changing the coolant on a 4th gen Firebird V6 after replacing the coolant elbows. There are some slight differences from the FWD 3800, such as a non-pressurized coolant tank on the F-body, but it shouldn't be this difficult, right?

When I first drained the coolant, hardly anything came out, maybe a few quarts at most. This is understandable, since I knew it was leaking and would be low. The manual says it takes 12 quarts, or 3 gallons.

My plan is to fill it with water, run it a bit, drain it, then refill with coolant. I have Peak 10x concentrate and the Lisle coolant funnel.

Unfortunately, I'm not able to add that much water to rinse it with! I have the heater on, and the coolant temp gauge says it's just under 210F. However, I have yet to hear the fans turn on, and it had been running for more than a few minutes! I replaced the thermostat last year with an OEM thermostat. The heat was on full blast.

This is the first time I'm flushing the coolant on this car, but not the first time I've ever changed coolant. Every other car I've replaced the coolant on, I was able to refill with the capacity stated in the manual.

Is there a trick I'm missing?

 

[zzyzzx]

Exactly how did you drain it?

 

[slacktide_bitog]

Exactly how did you drain it?

I drained it from the radiator drain petcock. The radiator cap was also open.

 

[zzyzzx]

OK, so no hose was disconnected, and you didn't run the engine for a few seconds (emphasis on seconds) to potentially push out any extra. Is it possible to completely remove the radiator drain without breaking anything?

 

[slacktide_bitog]

OK, so no hose was disconnected, and you didn't run the engine for a few seconds (emphasis on seconds) to potentially push out any extra. Is it possible to completely remove the radiator drain without breaking anything?

No hose was disconnected. You usually don't have to. I couldn't run the engine since the battery wasn't charged, and I had to disconnect it to replace the alternator.

I did completely remove the radiator drain, and nothing was broken after doing so.

 

[JohnnyJohnson]

I've had this DIY problem before. So this is what I did. I drained the radiator and refilled it with distilled water. Then I took the car out and ran it until the engine reached full temperature. I repeated that process. Drained it again and filled the radiator with concentrated Anti-freeze that was two years ago everything seems to be fine. I did check the Anti-freeze level with a meter to make sure it was adequate.

 

[BHopkins]

Didn't GM put a little brass bleeder screw on most of the 3800 engines? Follow the upper radiator hose and heater hoses, to locate the highest point in the coolant system. There should be a bleeder screw. I believe if you open it a few turns, and allow the air and bubbles to escape, while adding coolant to the system, until only coolant comes out of the bleeder. Then close it and you should have a full system.

 

[slacktide_bitog]

The official procedure in the service manual for this car says to remove the knock sensors.

Didn't GM put a little brass bleeder screw on most of the 3800 engines? Follow the upper radiator hose and heater hoses, to locate the highest point in the coolant system. There should be a bleeder screw. I believe if you open it a few turns, and allow the air and bubbles to escape, while adding coolant to the system, until only coolant comes out of the bleeder. Then close it and you should have a full system.

Most cars have some kind of bleeder valve, including the 3800. However, using it isn't always necessary when you have the Lisle coolant funnel.

I am not having issues with air in the system.

 

[dumkid]

Do both radiator hoses attach up high on the engine? On my car both radiator hoses attach to the thermostat housing, and the thermostat housing is above the level of the heads. So if I use the radiator petcock, I drain the radiator, and the radiator hoses. The engine remains full of coolant

 

[slacktide_bitog]

Do both radiator hoses attach up high on the engine? On my car both radiator hoses attach to the thermostat housing, and the thermostat housing is above the level of the heads. So if I use the radiator petcock, I drain the radiator, and the radiator hoses. The engine remains full of coolant

Yes, I think they both go pretty high on the engine.

 

[slacktide_bitog]

It seems like nobody has ever removed knock sensors on a RWD 3800! There are absolutely NO videos or pics of the knock sensors on a V6 Camaro or Firebird

There are plenty of LS1 F-body knock sensor videos, and of course the FWD 3800 knock sensors, but no V6 Firebird or Camaro knock sensor videos at all.

I even tried looking for videos on the Australian RWD Holdens that also used the 3800, and again got nothing!

 

[The Critic]

Just buy a vacuum filler.

 

[zulf200]

You can remove the knock sensors to drain the complete engine like GM says or you can also remove 1 long bolt from the waterpump, the ones that require the ptfe paste.

The pump location is pretty down low and drains the heads and intake manifold down to the timing cover level. a low volume remains in the block after this. (this is how I drain to prep for a manifold job anyway)

Drain the radiator from the drain plug, you will get about 70% out.

It you have debris in the system you will want to remove the knock sensors, be ready to poke a hole in the settled trash there to allow draining from both banks.

 

[Blinker]

Always use the bleeder screw when servicing the GM 3800.

 

[Chris142]

I drained it from the radiator drain petcock. The radiator cap was also open.

That will only drain the radiator. If memory serves me right both hoses go up high on the engine. The only way to drain that one is to get to the block drain plugs or knock out a freeze plug

 

[slacktide_bitog]

That will only drain the radiator. If memory serves me right both hoses go up high on the engine. The only way to drain that one is to get to the block drain plugs or knock out a freeze plug

In this case, the block drain plugs are the knock sensors. There is one on each side of the engine.