Hey guys. I haven't had good heat for the last 3 winters(luke warm). Its time i do something about it. I did a lot of searching and it looks like i need to flush out my heater core.

My question is, how have you guys done this with the garden hose. Do you hook the garden hose up at the outlet side at the fire wall or do you disconnect it from the block. OR have you guys removed the core before doing this and done it out of the vehicle. Any other tips would be great.

Normally I'd just go out and attempt to do it but I will have to go to my folks house so I can use a hose that's garage covered and slightly warmer. I have my hose hookup shut off for the winter to keep pipes from freezing and only an open driveway. I just don't want to be out in the freezing cold playing with this for hours. Thanks

 

Yeah, just hook it up to the outlet side where it comes out of the firewall - and unhook the inlet side...
I just did mine the other day. Unfortunatly I didnt notice a huge improvement.

 

flush it forwards and backwards w/ heater control fully "on". I did this recently and it worked wonders...

Warren

 

To all,

This "heater core flush", is it common for 4Runners? I have a 1988 4Runner that puts out great heat... when the truck is driving over 20 mph. When it is idling, it blows cold air. The truck is not over heating, but I figured I would change out the heater core.

Thanks.

 

Even mine is not as hot as I would like so I may try the backflush this spring and see if it makes any difference.

 

Mine was blowing out semi warm air,almost cold.I did this flush with the hose and it blows out so hot now you almost can't keep your hand in front of it.You'de be amazed at how much junk comes out.Flush it both directions until clean water is coming out.

 

Also, if flushing isn't doing the trick, check that the vent door is fully opening and closing as you move the heater control from cold to hot. On my '86 the flap is behind the console on the passenger side.

Warren

 

I dont think the 1st gens have a flap - they do have a water valve that is attached to the firewall on the driver side that can get stuck shut ( mine was )