Fox Coolant Flush & Fill - Non Running Engine

R82148V

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May 26, 2020
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Hello!

Hope everyone is doing well and stay safe!

Just some questions about Flushing and filling the cooling system on an 87' vert. I'm probably overthinking this, but I always want to make sure and cant see to find anything concrete on the net.
I'm bringing back to life my 87 vert after sitting for 12+ years. I've owned it since 1994 and always taken extreme care of it with constant maintenance. At this time I have just about everything off and out of the engine bay for cleaning and painting, except the cooling system. The coolant is still green from what I can see taking the rad cap off... The Rad is only 3/4 filled.

Question 1 - Is it safe to flush the heater core, Rad, Engine, all separately without being able to start the engine? It'll be a long while before that.
Question 2 - Is there any way to spin the water pump to possibly simulate a running engine? like use a drill with a rubber wheel against the water pump? I dunno haha
Question 3 - is it safe or even necessary to use one of those Power flushers that use a compressor
Question 4 - again, is it safe or even necessary to use those vacuum coolant fill systems to help minimize any air pockets?

I just don't know what to do or what my options are since the engine is not running at this time.
Should I even do a flush and just top off the RAD keeping the stat out of the car until I can get the engine up and running?

Thank you everyone for all your time reading this and help! :)
 
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General karthief

wonder how much it would cost to ship you a pair
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Drain enough coolant (3/4 full may be enough, I'd do about half full) pull the t stat and replace it with a 190 (192 is stock) t stat and run it around town a few times (keeping eye on temp of course) and then drain/flush with water then refill with coolant (50/50?). You may find that after the first couple trips you will need to replace stuff like water pump, hoses or worse yet the heater core.
 
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MustangIIMatt

Easy there, this ain't a dating site.
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Drain enough coolant (3/4 full may be enough, I'd do about half full) pull the t stat and replace it with a 190 (192 is stock) t stat and run it around town a few times (keeping eye on temp of course) and then drain/flush with water then refill with coolant (50/50?). You may find that after the first couple trips you will need to replace stuff like water pump, hoses or worse yet the heater core.

Ummm....


I just don't know what to do or what my options are since the engine is not running at this time.
Should I even do a flush and just top off the RAD keeping the stat out of the car until I can get the engine up and running?

My take? Get it running first, then flush it. It's a lot easier with the help of the water pump and the heat from the engine running.
 

Mustang5L5

Put lubricant all over the balls
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If the engine isn't running, just flush the radiator and heater core with a garden hose through disconnected hoses. For the engine, put the hose in the radiator water neck in the intake manifold, and let it flush out the bottom radiator hose. Obviously you will need to catch the flushed water.
 
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General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
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Ummm....




My take? Get it running first, then flush it. It's a lot easier with the help of the water pump and the heat from the engine running.
WHATTT? Matt, this is what I would do, I figure getting the engine running was a given! Come on, we all know I don't always do the correct expert mechanic thing because well, I'm not a mechanic.
Do I have to post my disclaimer everytime I answer a request for an opjnion? Ok. :jester:
DISCLAIMER: The information given is an opinion and not based on any real mechanical experience.
@R82148V I'm just bust'n Matts chops only because he is a phenomenal mechanic and I'm jealous (he has all the 'cool' tools)
 
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R82148V

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May 26, 2020
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WHATTT? Matt, this is what I would do, I figure getting the engine running was a given! Come on, we all know I don't always do the correct expert mechanic thing because well, I'm not a mechanic.
Do I have to post my disclaimer everytime I answer a request for an opjnion? Ok. :jester:
DISCLAIMER: The information given is an opinion and not based on any real mechanical experience.
@R82148V I'm just bust'n Matts chops only because he is a phenomenal mechanic and I'm jealous (he has all the 'cool' tools)
Hahah good stuff! You gotta bust some chops every now and then.

So basically, its best to wait, get the car running first before any type of coolant flush and fill.???

The Coolant has been in there for so long, I though it would a good idea and able to do it even though the car doesnt run.. I was just nervous how I would be able to circulate the regular water from the flush, out of the car without the water pump turning.. From the most part, the coolant in there doesnt look too bad. A darker Green but still green..

I know you can do a vacuum coolant fill but didnt know how well it would work to get all the air pockets out, etc....
 

R82148V

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May 26, 2020
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Hahah good stuff! You gotta bust some chops every now and then.

So basically, its best to wait, get the car running first before any type of coolant flush and fill.???

The Coolant has been in there for so long, I though it would a good idea and able to do it even though the car doesnt run.. I was just nervous how I would be able to circulate the regular water from the flush, out of the car without the water pump turning.. From the most part, the coolant in there doesnt look too bad. A darker Green but still green..

I know you can do a vacuum coolant fill but didnt know how well it would work to get all the air pockets out, etc....
was thinking of using a hand drill with a rubber wheel against the pump to simulate the car running.. pfff
 

nickyb

WAIT,you now have a pair?
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When you do get her running and drain / flush coolant , it's a good idea to get one of those funnels that come with radiator caps/ adapters( got mine on Amazon )
You can fill the system and get the air out easily,and they are cheap enough. Post some pics of her.
 

R82148V

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May 26, 2020
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Flushing the heater core and rad separately, make sense how to do, but when you "flush" the engine, how exactly do you go by doing that? goofy question i know..

Do you just remove the t-sat, reinstall the t-sat housing, disconnect the rad hoses at the rad, put the lower rad hose in bucket, garden hose in upper rad hose and flush until clean? Once clean, just reinstall the t-sat, hoses and add either coolant / distilled water or 50 50 mix?

I dont want to attempt to remove the engine plugs since the car is an 87. I'm sure they are in there for good.

Thanks!!
 

MustangIIMatt

Easy there, this ain't a dating site.
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Flushing the heater core and rad separately, make sense how to do, but when you "flush" the engine, how exactly do you go by doing that? goofy question i know..

Do you just remove the t-sat, reinstall the t-sat housing, disconnect the rad hoses at the rad, put the lower rad hose in bucket, garden hose in upper rad hose and flush until clean? Once clean, just reinstall the t-sat, hoses and add either coolant / distilled water or 50 50 mix?

I dont want to attempt to remove the engine plugs since the car is an 87. I'm sure they are in there for good.

Thanks!!
I usually do this, except that I leave the radiator in the loop so that it gets flushed too unless the block is particularly rust. (Then I do them separately.)