1996 LX450: Replaced coolant hoses and thermostat and now having flushing issues and no heat. (1 Viewer)

[WannaCruise]

Hello all,

I think I might be overthinking this, but after replacing almost all of the coolant and heater hoses (still need to do the ones under the intake) on my 1996 LX450 I started the refill process and I'm stuck... I refilled the radiator with about 1.25 gallons of distilled water and started the car and set the heat to high. After a few minutes the temp gauge was showing normal running temps, but it seems the thermostat (new Toyota part) doesn't seem to be opening and I am getting no heat from the vents. In addition, the water level in the radiator was not budging, and there were no bubbles coming out.

I ran the car for about 5 minutes and the temp gauge never went above 1/2, but I was concerned that something was wrong so I just turned the car off. Am I missing something here? Did I need to just keep running the car until the thermostat opens?

Any suggestions? I feel like an idiot here because this is the most basic of basic tasks... Thanks everyone.

 

[manofthewoods]

Hello all,

I think I might be overthinking this, but after replacing almost all of the coolant and heater hoses (still need to do the ones under the intake) on my 1996 LX450 I started the refill process and I'm stuck... I refilled the radiator with about 1.25 gallons of distilled water and started the car and set the heat to high. After a few minutes the temp gauge was showing normal running temps, but it seems the thermostat (new Toyota part) doesn't seem to be opening and I am getting no heat from the vents. In addition, the water level in the radiator was not budging, and there were no bubbles coming out.

I ran the car for about 5 minutes and the temp gauge never went above 1/2, but I was concerned that something was wrong so I just turned the car off. Am I missing something here? Did I need to just keep running the car until the thermostat opens?

Any suggestions? I feel like an idiot here because this is the most basic of basic tasks... Thanks everyone.

Did you properly position the thermostat? The jiggle valve needs to be up, That detail is easy to overlook.

 

[greentruck]

Always helps to have the nose up in the air a little, like parking on a sloped drive, etc. The issue with the 80 series may be the rear heater and lines. That should help things burp better.

 

[WannaCruise]

Did you properly position the thermostat? The jiggle valve needs to be up, That detail is easy to overlook.

I'm usually very diligent about that, but I will check it. My concern is that it's acting like the thermostat isn't opening. The "supply side" of the thermostat is still cool while the block is warm.

My next step is to just pull the thermostat while I flush everything.

 

[WannaCruise]

Always helps to have the nose up in the air a little, like parking on a sloped drive, etc. The issue with the 80 series may be the rear heater and lines. That should help things burp better.

Agreed, and I'm up on ramps, but I'm not even at the point of bleeding. I need the coolant to start circulating in the radiator for that to happen.

 

[Irish Reiver]

I think you are overthinking it. If the jiggle valve is correctly oriented then top of the radiator and make sure the resevoir has plenty of coolant. Go for a short drive to get your operating temps up then drive home, turn it off and let it sit. Any air will have been pushed out when you drove it and the "missing" coolant will be sucked in from the reservoir as the engine cools.
Obviously all of the above is only applicable providing you have no coolant leaks.

 

[WannaCruise]

I think you are overthinking it. If the jiggle valve is correctly oriented then top of the radiator and make sure the resevoir has plenty of coolant. Go for a short drive to get your operating temps up then drive home, turn it off and let it sit. Any air will have been pushed out when you drove it and the "missing" coolant will be sucked in from the reservoir as the engine cools.
Obviously all of the above is only applicable providing you have no coolant leaks.

I'm sure you're right, no leaks, and I pressure tested prior to refilling. My worry is that I only got 1.25 gallons of distilled water in it after replacing the main coolant hoses, PHH, and most other heater hoses. I expected to get get it up to temp, the thermostat to open, it'd start circulating through the system, and then add more. After 10 minutes of idling, temp gauge at 1/2, I was getting nothing. And there was no heat coming from either the dash or rear heater.

 

[WannaCruise]

OK, quick update.

I ended up pulling off the upper coolant hose and filled added another gallon of distilled water before it was full. I reconnected the hose, and started the car up. Within 5 minutes I had heat and temp gauge was at 1/2 like before. After about 3-4 more minutes The coolant hoses were still relatively cool. I idled at about 2k RPM for 3-4 more minutes and after that the upper hose was warm and thermostat must have opened. I ran the car for 30 minutes, alternating interior temp from hot to cold every 5 minutes or so.

Tomorrow I will drain and refill with distilled again to flush the Prestone coolant cleaner I added the first time. Then it's in with Toyota Red.

Fingers crossed that this will work OK.

 

[LandCruisinMy93]

Happy to see the thermostat working. PSA HIJACK...always test your new thermostat in using a thermometer and boiling water before installing.

I do this as an old habit, however, when I first purchased and baselined my 80 I had a failed toyota thermostat from the dealership that would not open. Luckily I caught it in the pot and not on the road.

 

[WannaCruise]

I think I need to consider replacing the radiator soon as it's turning they grey/green color... Is the Denso radiator truly an OE part?

Answered this myself... No... not it's not. I had gone Denso for an AC Condenser, and that was basically a Toyota Part in a non-toyota box, but the radiators seem to be different. I'll keep hunting an original one. Hopefully another 20%+ off deal comes around again.

 

[jonheld]

I think I need to consider replacing the radiator soon as it's turning they grey/green color... Is the Denso radiator truly an OE part?

Answered this myself... No... not it's not. I had gone Denso for an AC Condenser, and that was basically a Toyota Part in a non-toyota box, but the radiators seem to be different. I'll keep hunting an original one. Hopefully another 20%+ off deal comes around again.

Toyorad is the OEM for the radiator.

 

[WannaCruise]

OK, so I've done this twice now and I think I've got it down. I also think I figured out my issue...

I was getting no coolant in the block because I had the left wheel off, but the right wheel is still on the ground. This is putting the driver side of the radiator slightly above the passenger side so the upper hose is ABOVE the radiator fill port. No wonder I wasn't getting coolant there, the radiator was "filling up" before it reached the upper hose.

Sometimes it's the simple things...

The next issue to address is that I accidentally bought 2 gallons of SLLC (premix) instead of LLC. Doh!