OK new to this but heres the deal. 95 runner heat basically stopped working, would occasionally work and then just quit. No antifreeze on the floor. Replaced thermostat. Old one inside gasket bad shape. put in antifreeze, fired up, and ran to temp. Gauge wouldnt really register at all and then all of a sudden it shot up to 3/4 hot. Then made its way up to just below the redline on temp gauge. Shut it down, let it cool a few and then popped radiator cap. Lotsa steam but nothing else. Refilled antifreeze, left cap off and fired up to check if coolant would move when it hit temp. No movement then it starting spurting lots of antifreeze out the radiator.

Do I need to flush the system and if so how? Is there a possible water pump issue or am I just plain missing something easy. Any help would be awesome. Ol ladies rig and tryin to keep her happy if ya know what I mean.

Thanks JBBAD

 

Did you run it up to temp with the radiator cap off, and top off the system as it needed? If not, make sure it is cool, with the heater contol on full hot, and parking on a slight incline (front higher) helps. Take the radiator cap off, then start the engine, and keep an eye on the coolant level as it warms up, and top off as necessary. What you are doing here is making sure that you evacuate all air from the system, with the thermostat open.

When you are confident that the system is full, you can replace the cap, and road test it (checking heater along the way).

 

One of my previous 4Runners had the impeller (sp?) of the water pump rusted clean off, causing the head gasket to fail. Check to make sure the pump is working properly (may have to remove it)

 

Are you sure the new thermostat is the proper one, meaning opens up at proper temp?

 

Am going to try the top off the radiator thing. Second person today that told me that. Thanks a ton for the advice, will let ya know how it goes.

Peace jbbad:bigclap:

 

when filling coolant I also pull the heater hose at the heater control valve on the firewall. This seems to be the highest point in the cooling system. Fill the radiator untill coolant runs out of the hose and reconnect. proceed warming up with the rad cap off untill warm. This method helps pull all of the air pockets out of the coolant

 

Hi again all, have replaced the heater core and I must say not looking forward to ever having to do that again. The heater works great now and the truck ran great for a few hours then bam, engine check light cam on and started running rough again. No changes to the heat (still good to go there). Any help or ideas is appreciated as I am out of them.

 

Sounds like it might be a head gasket leak. You could pressure test the cooling system (to see if it is being pressurized by the engine compression) or do a chemical test on the coolant to detect exhaust gas contamination. Napa usually carries a test kit for that, costs about $20.

 

Hi thanks for that suggestion but I ran a compression check and all cylinders were between 168 and 172

 

But it may be a high pressure leak between the cylinder and the cooling system, not uncommon, has happened to me several times. Typically only happens at high engine loads when you get the highest pressures inside the cylinders. Pressure testing the "cooling system" is different from compression testing. You seal up the radiator with a pump and gauge and see what the pressure does as the engine revs change.

 

One thing that adds to your theory maybe is the fact that at higher RPMs the heat gets hotter. Sounds like that may be the case. What is the test I should run called? Yolu say a chemical test on the coolant. Never heard of it?

 

Also would that cause it to run like crap at idle and smoke like crazy?

 

Pressure test the cooling system (look for pressure rising with engine RPMs), or try a chemical test:
- http://www.arrowheadradiator.com/hea..._leak_test.htm

 

Question,

I had my timinng chain eat a hole in my timing chain cover and leak coolant into the oil. I'm replacing my chain with a dual kit, but is there anything else I need to replace with all that coolant being in the oil, or would a simple flush take care of it? Thanks in advance.

Mave

 

Timing chain cover for one. Either repair it or replace it. Unless the hole is fixed, oil and coolant will continue to mix. Try a junkyard or http://www.Engnbldr.com/ for replacement.

 

Well, after a month and a half with a surgery thrown in the middle I got the head gaskets replaced on the wife's 4 runner. It was actually pretty fun but a lot of work. One thing that was huge and I wish i would have taken more of but i snapped about 8 digital pics throughout the process. Was huge in getting the hoses hooked back up. I also replaced the timing belt. What took longer then anything after getting the heads back nice and shaved and a bath thrown in I liked how clean they looked. Then I spent 3 more hours cleaning all the gunk the bath left on em. Then of course I couldnt attach nasty parts to my pretty heads. Then of course I couldnt attach nasty parts to these new pretty clean parts. Get the picture heh?? Anyways first time I have done this and it fired up right away. Only problem I see is a fast idle. It idles at about 1500 rpm at temp. I would like to kick it down to around 1000 but it is fuel injected. Do I have a hose hooked up wrong maybe? Any advice is greatly appreciated. Wifes happy, woohoo....

Peace