Coolant Drain Plug on '78 Plymouth Volare

VolareMom

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Hello!
I am needing to locate the coolant drain plug(s) on the cylinder block on my '78 Plymouth Volare. Wanting to do a coolant flush and fluid replacement, but unsure where it is.
Pictures would help.
Please and thank you.

~Volare Mom
 

XfbodyX

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Long ago some would put petcocks in the blocks for ease of draining, many still does today.

On our Fs we have small threaded steel plugs that have been in for over 40 years and most become one with the block. So much can go wrong removing them for the small benefit. If you could easily get to them they are still hard to remove from rounding off the top to pulling some threads from the plug or the block. Many times with the block out of the car Ive had to resort to welding a lug nut on the steel plug to get it out with a little heat and even then Sunday morning after church might be the best time to try.

They sit very low in the wet area of the block and most are covered with scale and casting materials so if you did get them out for the first timer it might not be the best to be poking a coat hanger or worse yet a small sharp item on the scaled areas of the cylinders in the water jacket.

If you must try, I hope it works for you but its really not needed to flush your system. If its overheating now pre flush you may or may not gain much if the core is semi plugged.

But if you must.... here is a V8, you never said V8 or /6

Right behind the motor mounts.

So in this pic youd be looking up and the pan would be on, see the pain rail and the motor mount bosses then right behind in the circle is where the plug goes.

DSC00029.JPG
 

VolareMom

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Long ago some would put petcocks in the blocks for ease of draining, many still does today.

On our Fs we have small threaded steel plugs that have been in for over 40 years and most become one with the block. So much can go wrong removing them for the small benefit. If you could easily get to them they are still hard to remove from rounding off the top to pulling some threads from the plug or the block. Many times with the block out of the car Ive had to resort to welding a lug nut on the steel plug to get it out with a little heat and even then Sunday morning after church might be the best time to try.

They sit very low in the wet area of the block and most are covered with scale and casting materials so if you did get them out for the first timer it might not be the best to be poking a coat hanger or worse yet a small sharp item on the scaled areas of the cylinders in the water jacket.

If you must try, I hope it works for you but its really not needed to flush your system. If its overheating now pre flush you may or may not gain much if the core is semi plugged.

But if you must.... here is a V8, you never said V8 or /6

Right behind the motor mounts.

So in this pic youd be looking up and the pan would be on, see the pain rail and the motor mount bosses then right behind in the circle is where the plug goes.

View attachment 48101
Sorry and thank you. Mine is a V8. I wasn't able to work on it for quite some time. It has sat and the coolant needs to be flushed before I try to start it up again. I can remove the reservoir, clean it out, reattach, and remove the drainage plug on the radiator and flush with a hose that way, but I was worried that if anything was gunked up past that point, it would make matters worse. ~Volare Mom
 

XfbodyX

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Take the T stat out and put the garden hose in the top and let it run out the bottom hose, then wrap the hose in a towel and stuff it in the bottom hose and let it back flush through the top. The backwards flow will really push some junk out.

Sorta generic but there is no set formula or ways to do a flush in one thats sat for a while.

No one says you cant flush things the best you can and do the fire up with straight water then drain. Id do it a couple times before the perm antifreeze.

Its not a huge task no matter what approach you use.

Maybe others have equal or better ways they can post about.


Good luck.
 

Mikes5thAve

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I've never tried to take them out unless the engine is out of the car. Do a normal flush and drive it a few days and do one again if you think it's bad. You can also disconnect the heater hoses and put a garden hose T in there and flush that way with the lower rad hose disconnected.
 

kmccabe56

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If your engine is full of crusty stuff, or gunk in general, the most effective cleaner I've ever used is oxalic acid. Used to be able to buy a small two part container. Oxalic acid on one side, baking soda on the other.

If you find oxalic acid, you need the baking soda otherwise the oxalic acid will continue to eat and it won't be pretty.
 
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