22 RE Overheating ??? (1 Viewer)

Joined
Oct 18, 2005
Messages
357
Location
Murrieta
I have an 87' 4runner w/ a 22re.

1.) It gets hot, then the thermostat opens up
and the temp goes back to normal.

2.) The back heater is hotter than the front?? (We need both heaters
here where the snow flies.)

Waterpump? Heater core?
I have replaced the clutchfan. Thought it would cure the overheating issue.
New thermostat and flushed the radiator.

Anyone have any suggestions?
Thanks,
PRF
 
Joined
Dec 8, 2002
Messages
280
Location
Cincinnati
Drill an 1/8" hole on the Tstat.

Your main heater core most likely has some crud built up in it from years of use. You can try to flush it. Also cheh the valve on the firewall and make sure it is opening all the way.
 

KLF

Frame waxer
SILVER Star
Joined
Apr 5, 2003
Messages
8,755
Location
Southern NH
 
 
 
purerockfury said:
1.) It gets hot, then the thermostat opens up
and the temp goes back to normal.
Read this: http://www.4crawler.com/4x4/CheapTricks/index.shtml#Thermostat. Buy and install the 2-stage thermostat. End of problem.

2.) The back heater is hotter than the front?? (We need both heaters here where the snow flies.)
Your front heater core is probably all crusty inside, partially blocked. Or, there's a bunch of leaves and pine needle crap that got sucked into the blower fan, and is now blocking the flow thru the eveporator coil (if you have AC) or thru the heater core. You can try acidizing the heater core with some hardware store Muriatic Acid, it might help.

Pray to the almighty Toyota gods for mercy that you don't have to pull the heater core out. The ENTIRE FREEKING DASH has to come out to get the heater box out, and you pretty much have to discharge the AC refrigerant. It's a huge job that will have you cursing the day you bought that damned truck. Then you'll be stuck converting to R143a, because there's not a shop on this planet that will install R12 now.
 
Joined
Oct 18, 2005
Messages
357
Location
Murrieta
Thanks KLF,

When using Muriatic Acid do I flush out
the system afterwards?

I also heard of reversing the in/out hoses
to the firewall to blow out the gunk in the
heater core. Does this work or does it do
more damage than good?

I hope and pray it's not a heater core problem.
Unfortunately it is my DD too.

The heater does blow warm air, but not like the rear.

PRF
 

KLF

Frame waxer
SILVER Star
Joined
Apr 5, 2003
Messages
8,755
Location
Southern NH
 
 
 
Honestly, I've never done the job, but the way I understand it is you disconnect both heater hoses (good luck with the 22RE valve cover in the way :( ), then take compressed air and GENTLY blow out all the coolant. Pour the Muriatic Acid in, let it sit for 20-30 mins. Then start flushing it out with LOTS of water. It's VERY important not to get any acid in the engine coolant passages, it will eat away the aluminum head very quickly!

I'm not really sure on the time, and I'm no chemist, that's for sure. You might want to ask someone that knows more about chemistry and reactin times, etc.
 
Joined
Dec 8, 2002
Messages
280
Location
Cincinnati
I just pulled the hoses off the core, and put the garden hose to the outlet to reverse flush it.

Never done the Acid trick, but been thinking about it on my van.
 

Users Who Are Viewing This Thread (Users: 0, Guests: 1)

Top Bottom