radiator flush 1970 (1 Viewer)

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flushing the radiator. where is the radiator drain plug. 1970 fj40 with 2f 4spd.
can any one help me out? thanx
 
please guys i really need help
 
I don't know where it is on a '70, but you can always just pull the lower radiator hose. It makes more of a mess, but it will drain way faster.
 
Front passenger side should be the pep cock, Cant miss it. has a wing nut type of fitting on the bottom of it. Unscrew that and it will drain the radiator.. If there isnt one there you will need to pull the bottom hose. as someone has welded it closed. I have had both.
 
Let me suggest you also drain the engine block, drain cock at the drivers side rear of the engine. It is an area where stuff tends to settle, and turn to concrete if you don't wash it out periodically.
 
What about using a pressure washer to get crud out of the engine block - is this a good practice?

I've seen a few guys do it but wasn't sure that much pressure was good or not? Maybe just lots of time with the garden hose instead?
 
haystax said:
What about using a pressure washer to get crud out of the engine block - is this a good practice?

I've seen a few guys do it but wasn't sure that much pressure was good or not? Maybe just lots of time with the garden hose instead?

I know the pros use pressurized systems to flush the block. I don't know how much, and I would also say it is hard to get much pressure/turbulence going in some of the corners. I have used a garden hose to not much effect. It took a long screwdriver with the head off of the block to clean the crud out of mine (enough that the block drain opened up!).

I also believe the Prestone radiator cleaner stuff helps.
 
I have a 70 and the radiator drain is on the bottom of the radiator on the passenger side. looks like a nipple with a rod through it. Might need some pliers to turn it as it's probably rusted.
 
thank for the info. I looked to the passenger lower side of the radiator for that screw and Couldnt find it. Im sure someone must have welded it shut or something. I am probably going to have to drain it by the hose at the bottom .
 
There's an obvious hole in the radiator support frame bottom for the drain. I don't know why someone would braze or solder it shut, but I suppose they do. I had one radiator where a threaded plug was just used: it was basically flush with the bottom of the radiator.
 
john0089 said:
I flushed my radiator and over 50 acorns fell out....kinda scary. :rolleyes:

Fer cryin' out loud! Keep the cap on, and start shootin' them there feather-tailed rats before they eat yer wirin'! :eek:

My 82 FJ40 came with hardware cloth over the exhaust pipe - keeps the chipmunks, squirrels (small ones!), and mice from nesting in the muffler.

It is beer-spew-inducing to watch half a dozen gasping, half-gassed chipmunks tumble out an exhaust pipe! :D

Kirk :beer:
 
wow .......... doesnt get any weirder than that.
 
what else should i replace as part of the cooling system while im flushing the radiator. I am already going to replace thermostat, thersmostat gaskets.

what else could i do for this summer to keep it very cool. i know almost nothing else of the cooling system.

should i replace the water pump?
water temp sending unit?

ex.....
 
If they are working, leave them alone. If the water pump is making a loud squealing, think about that. If your fan belt is old/cracked, there's a good time to do it.
 
okie said:
what else should i replace as part of the cooling system while im flushing the radiator. I am already going to replace thermostat, thersmostat gaskets.

what else could i do for this summer to keep it very cool. i know almost nothing else of the cooling system.

should i replace the water pump?
water temp sending unit?

ex.....

My water pump was fine until I put all new coolant hoses on. The weep hole began to drip the same day after it was fired back up.
 
I would bypass the heater core by connecting the input and output hoses together with a piece of copper tubing. Use a good caustic flush chemical, the one you must neutralize. All the small stuff you knock loose tends to collect in the heater core as the tubes are smaller than any other part of the cooling system. Old school guys use drain-o. If you do find the drain for the radiator, it may be plugged with the same concrete IDave spoke of. You can get it to drain by completely removing the petcock and gently poking it with something blunt. That's what I had to do, so I just pulled the radiator and had it hot tanked and pressure tested. I also wore a fair amount of coolant when the drain finally opened.



GL

Ed
 
I got concrete! Tried a flush with fresh water by inserting a garden hose in the smaller hose that goes from the stat to the water pump and not even a drip of water out of the engine drain. Yep...engine drain is completly blocked. I've replaced my radiator with a new one but not hooked up yet. What method (short of an engine tear down) can I use to clear it up?

I was thinking of connecting a hose to bypass the radiator (I don't want any crap in there cause it's new), and adding some commercial radiator flush and then starting the engine let her get warm and circulate a little. Hopefully with the chemical bath this'll clear the arteries. Does this sound reasonable? AND... what product should I use? Drano?
 
I was successful hand drilling out the crap at the engine drain with a piece of coathanger wire (it makes an L turn about 1 inch into the block) on one of the engines I worked on. Took a bit of time doing it, though. Other times, it was from the top.

TSP, or a mix of muriatic acid with water 1:3 dilution, or Prestone's super stuff helps.
 

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