coolant not draining on 383 rr

[TRAMO]

I am having a over heat problem.i open the rad drain and all I got was about a gallon of coolant but I took off the bottom hose and the rest came pouring out( aprox 1 1/2 gallon) does this mean my radiator is stopped up or was the coolant in the block didn't come out because of air lock?

 

[Basket case]

stick your garden hone in the filler neck, with the bottom hose off, and see if water comes out the bottom. if it doesn't, you are plugged up.

 

[AMX364]

And or remove thermostat and put hose there. The thermostat does like having a small vent hole for airlock issues.

 

[69a100]

Did you have the rad cap on when you did this? If so the vacuum of a closed up system would cause that to happen. Good Luck

 

[TRAMO]

rad cap was off and drain wide open.new thermostat had small air hole

 

[Dako]

If you have a shop locally that still does radiator repair, take it in for a test flow. If this is the original (just plain, old) radiator and you are having an overheating problem...and drainage stopped early from the draincock, you likely have a radiator that has deposits built up in it. You can get it opened up and rodded out, or replace it.

 

[MoparHonda]

Did you open those two drain plugs in the engine block?

It's possible some previous owner used Stop Leak and plugged everything up, happend to me.

 

[Cornpatch MO]

Did you open those two drain plugs in the engine block?

It's possible some previous owner used Stop Leak and plugged everything up, happend to me.

Take those drain cocks or plugs completely out and see if there is rust scale plugging the hole. I have seen that happen several times. The drain holes are near the bottom of the water jackets and that is where the sediment settles...............................MO.

 

[Slowburn]

Had a similar situation, opened the petcock got a dribble then nothing. It was the original radiator and all it took to get it to pour out was to snake a piece of wire in the drain hole then in poured out. During draining it would occasionally slow but after a quick snaking it would go back to flowing. It was filled with scale and sediment, I imagine you have a similar problem. We simply bought a replacement radiator and one of those coolant system flushing kits from Prestone since radiator shops are a thing of the past.

 

[g413]

About 45 years ago I had a very rusty cooling system on my 68RR. I had to replace all the freeze plugs, water pump and the radiator cap. I also had a radiator that had a lot of rusty gunk in the bottom. I agree that you should go to a radiator shop and have them look at it.

 

[sleepar]

If you have gunk in the radiator you will want to power flush the whole system heater core and the block or. The sediment will just cause more problems... I would suggest filling and flushing with water several times and then doubling the amount of 5minute flush and fun the car at temp being mindful not to over heat it for a few days then flush and repeat till it clears up and drain it from the block plugs because that's where most of it ends up at... I have used a brass pet clock there with a hose so it's not as messy both sides at the same time and try not to get burned run the heater on hottest.... other than repeated flushes I'd to hot tank the engine in a vat and the radiator shop along with every thing else.

 

[nm9stheham]

The small hole in the t-stat will let the coolant in the block drain out very slowly; if you had waited for an hour, you probably would have gotten a lot more out of the rad drain. That small hole is there for allowing air to slowly work out of the block when running. I would not focus on that for your overall heating issue.

First thing is to do as Cornpatch says: refill the system with water and remove the block drain plugs, and see if you get good flow. This is a good test to see how much sediment is in the block; in bad cases these will be completely blocked up; lots of sediment is a sign that you need to do repeated engine flushes and reverse flows into the block. Also stick your finger in each block drain hole and see how much sediment you can feel in the block. If they are badly plugged, I would remove the water pump and use those as points to put in water under pressure and try to drive out the block gunk.

The rad needs to be done separately. You can get a lot of crud out by reverse flushing (water into the bottom with the hose sealed into the bottom opening by stuffing a rag tightly around it to keep good pressure) and tapping all over the rad with a screwdriver handle or piece of wood; that will will dislodge a LOT of crap in the tubes and tanks. You have to do this for 15-20 minutes to get it really clean. I have cleaned out a badly stop-leaked rad this way.

If you want more help with your overheating, then it would be good for you to describe what exactly is happening and under what conditions.

 

[TRAMO]

THANX FOR ALL HELP. i think i fixed it.i had the rad cleaned but the shop wrecked it.i bought a new 3 row from classic and it fixed it.

 

[nm9stheham]

Good deal. Did you take the old rad part to see what they 'wrecked'? It would be good for everyone to know.