Radiator Drain capacity 2F (1 Viewer)

[Sacto60]

How much capacity should I expect when i do a simple radiator drain/fill? I opened up the rad drain plug, opened the rad cap, and maybe got about 1.25gal of coolant total. Good news is, what came out didn't look all that bad. But when I went to refill some distilled water and run it until hot, it took about 2.75gal of water. I'm parked on level street surface, did some upper hose burping, and ran it with heat on blast. I was able to add just a little more as the truck was running, but again wouldn't take much more- in fact, started to overflow. Temp never rose much at all. Isn't the 2F coolant system over 4gal? I realize there's likely some in the block, right? If the thermostat won't open while running the truck, I'm guessing that's the reason the volume caps at under 3gal?

 

[g-man]

How much capacity should I expect when i do a simple radiator drain/fill?

2.75 gals sound about right. Book says capacity is 17.4 US qts. but you're not going to get it all out.

Temp never rose much at all

Did you get it up to operating temps so that the thermostat would open?

in fact, started to overflow.

When it did this you should put the cap on it and let the thermostat open but watch the temps so the engine doesn't overheat.

If it starts to get too hot turn the motor off (well before your in the red but past 1/2 way mark)

disregard the above if you don't trust your temp gauge and get a heat gun and put it on the temp sensor on the head.

Park it uphill if you can to get the engine to burp. Or jack up the front of the truck. May need to cycle the heat on the engine a few times. Run it til it gets hot. Let it cool down so the coolant isn't going to blow all over you when you take off the cap. Then fill some more. Run it again etc. Squeezing the upper radiator to water pump hose will tell you when the t'stat opens. It will go from tight to a bit mushy and cold to hot. Fill slowly when you do add coolant. The neck on the radiator is small. Just trickle it in. Going fast can fool you into thinking the radiator is full.

 

[Sacto60]

Thanks, and I ended up just deciding on a new Tstat and thankfully the bolts came free. But...the damn Tstat was in there upside down. Driven better part of a decade w the damn thing upside down. So I ordered all new gaskets and bolts and will follow previous threads on this job. Not sure if the upper housing is okay though. Take a peek. The gasket surface looks ok but inside...

 

[g-man]

OEM Thermostat Housing Kit for '81 to '87 Land Cruiser FJ40 FJ60 with Oil Cooler

Complete kit to replace the thermostat housing assembly for Toyota Land Cruiser FJ60 or '81 to '84 FJ40 with oil cooler (as per U.S. spec). These upper and lower thermostat housings do not accommodate BVSV, thus should not be used on vehicles that need to be smog compliant, such as those in...

www.cityracerllc.com

Racer city has housings for sale. No hole for the BVSVs (the brass plug w/2 prongs for vaccuum lines)

Personally I'd just clean up the mating surface. Maybe a dremel with a small brush. Don't forget the round rubber gasket that sits on top of the t'stat. you can see it in the schematic and pics on the Racer City page.

 

[Dr. John]

The block drain valve is located just below the manifolds. Easy to get to from below.