Block Flush
Thread Starter
Instructor
Joined: Jun 2007
Posts: 157
Likes: 1
Block Flush
Is there any way to flush the block out while the car is up on ramps (inside so can't make a complete mess) with the reaiator out and the top and bottom hoses still connected?
The new radiatior will have fresh antifreze in it but would rathr not mix it with the old antifreeze in the block, hence the flush.
I put air in the top hose and got a little out from the bottom hose but no flush. I believe the thermostat is open and put 200 degree water in the top hose to be sure as it is a 180 degree in the car.
Is it the water pump preventing it from coming out or the fact the car is on ramps so the fluid can't travel up hill?
Just looking for suggestions how I might purge the block with the car on ramps and no radiator in it.
Thanks,
The new radiatior will have fresh antifreze in it but would rathr not mix it with the old antifreeze in the block, hence the flush.
I put air in the top hose and got a little out from the bottom hose but no flush. I believe the thermostat is open and put 200 degree water in the top hose to be sure as it is a 180 degree in the car.
Is it the water pump preventing it from coming out or the fact the car is on ramps so the fluid can't travel up hill?
Just looking for suggestions how I might purge the block with the car on ramps and no radiator in it.
Thanks,
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Do you have a fluid catch pan...a big one?
One each side of the block, down by the oil pan rail, there is a plug. Pull each plug one by one, and the fluid that is in the block will drain out into the pans. You can pour water in through the T-stat opening to flush it out until everything is clear.
One each side of the block, down by the oil pan rail, there is a plug. Pull each plug one by one, and the fluid that is in the block will drain out into the pans. You can pour water in through the T-stat opening to flush it out until everything is clear.
Safety Car
Joined: Sep 2007
Posts: 4,454
Likes: 328
From: Indy Indiana
I had tried in the past to get to those plugs and remove them for a block drain/flush... they are on real tight... I could not get them off.. I was afraid to try real hard.. if they break then its bye bye block... especially with the engine in the car... it would be a major cost to repair... labor wize....
just be careful....
just be careful....
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
I had tried in the past to get to those plugs and remove them for a block drain/flush... they are on real tight... I could not get them off.. I was afraid to try real hard.. if they break then its bye bye block... especially with the engine in the car... it would be a major cost to repair... labor wize....
just be careful....
just be careful....
If you use a six point socket they will likely come out and I wouldn't worry about them breaking. You can also tap a metric socket onto the plug so it's on there good and tight, and then get it out. I have battled a few very tough ones and never once have I seen a sheered drain plug before.
Racer
Joined: Feb 2008
Posts: 497
Likes: 0
From: Streator Illinois
I had tried in the past to get to those plugs and remove them for a block drain/flush... they are on real tight... I could not get them off.. I was afraid to try real hard.. if they break then its bye bye block... especially with the engine in the car... it would be a major cost to repair... labor wize....
just be careful....
just be careful....
The metric socket is a good idea if you can find one that will fit on really tight. Another way to remove it would be to weld a nut onto the plug head if it is rounded and then put a socket or wrench on that.
Depending on when and who installed the plugs, there could have been sealer used. You really do not need sealer when you reinstall the plugs.
Terry
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Race Director
Joined: Feb 1999
Posts: 19,659
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From: Lenoir City Tennessee
Ci 6, 8 & 10 Veteran
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15
When I removed the plugs on mine the plugs came out and then no water came out!!! There was a rust plug in the hole that came out only when I used a screwdriver to punch a hole in the rust. At that point, water comes out in a BIG hurrry for sure. Be ready for it when it does. This is the way to get all the water out of the block for sure though.
Safety Car
Joined: Aug 2006
Posts: 4,102
Likes: 1
From: Forsyth Illinois
This is right up my ally here.....I did the fiberglass,and paint work at the boat shop for some time,but also,winterized about 200 boats at the seasons end!
Here's a question on flushing,or rather what is there when you flush.When I got my 68 it had sat since 96.The intake,and water pump was full of this white pasty stuff.I mean full of it.I thought it was a key of coke that got moist,and turned to past.I got it all out w/a screw driver,and flushed the system,and it runs cool as could be,but that was weird.
The heads are Fuelie heads,but chromed,and was wondering if it caused some kinda reaction?????Just curious if anyone has ever seen this????
Here's a question on flushing,or rather what is there when you flush.When I got my 68 it had sat since 96.The intake,and water pump was full of this white pasty stuff.I mean full of it.I thought it was a key of coke that got moist,and turned to past.I got it all out w/a screw driver,and flushed the system,and it runs cool as could be,but that was weird.
The heads are Fuelie heads,but chromed,and was wondering if it caused some kinda reaction?????Just curious if anyone has ever seen this????
Thread Starter
Instructor
Joined: Jun 2007
Posts: 157
Likes: 1
I will try and remove the plugs this wekend however the car is on ramps so leverage may be an issue to exert enough force to remove them.
Question: Does it make sense to remove them and flush it out as the radiator is out being recored and I hate to install a new radiator and not flush the block.
How much antifreeze sholud I expxct to see per side? 1 gallon, 2 gallons, more??
Question: Does it make sense to remove them and flush it out as the radiator is out being recored and I hate to install a new radiator and not flush the block.
How much antifreeze sholud I expxct to see per side? 1 gallon, 2 gallons, more??
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
I will try and remove the plugs this wekend however the car is on ramps so leverage may be an issue to exert enough force to remove them.
Question: Does it make sense to remove them and flush it out as the radiator is out being recored and I hate to install a new radiator and not flush the block.
How much antifreeze sholud I expxct to see per side? 1 gallon, 2 gallons, more??
Question: Does it make sense to remove them and flush it out as the radiator is out being recored and I hate to install a new radiator and not flush the block.
How much antifreeze sholud I expxct to see per side? 1 gallon, 2 gallons, more??
Yes, flush it.
I doubt you'll move the car off of ramps even when really giving the plugs hell. Use a breaker bar for extra leverage.
Expect a gallon or less per side. Also expect that nothing will come out when you remove the plug until you use an awl or a screw driver to poke out any sediment that's clogging the drain port.
Melting Slicks
Joined: Apr 2001
Posts: 2,030
Likes: 363
From: Lubbock Texas
I wonder if it would be possible to replace the drain plugs with some kind of valve? My Tundra had a neat setup. It had valves with barbs for attaching a hose. Slap on a couple of hoses, direct them into a bucket, open the valves and the block was drained in no time.
DC
DC
Last edited by DC3; Dec 19, 2008 at 10:49 PM.
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
I install air compressor drain valves in mine, just as you describe. They have a snout that I slide a rubber hose over when I want to drain the block and it only takes a matter minutes. I can change a T-stat very easily. I drain a gallon or so from the engine and I can remove the upper radiator hose and housing without spilling a drop of coolant.
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Here are some pics I just took to help you locate them on the block, per side.
Driver's Side Plug Location:
Passenger Side Plug Location:
Thread Starter
Instructor
Joined: Jun 2007
Posts: 157
Likes: 1
Thanks for the fast reply and advice...Pics really help.
Looks to me like I will need to start removing plug wire chrome covers and such as I can't see either plug directly on ramps. I think I will need a lift to do this job...
Can I crank the car over without starting it and have it pump through the bottom hose as it turns over and the water pump pushses it out??
This plug finding and removal on ramps sucks!!!
Looks to me like I will need to start removing plug wire chrome covers and such as I can't see either plug directly on ramps. I think I will need a lift to do this job...
Can I crank the car over without starting it and have it pump through the bottom hose as it turns over and the water pump pushses it out??
This plug finding and removal on ramps sucks!!!
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
I don't see a need to turn the engine. The fluid on the front side will drain down and out of the water pump through the lower radiator hose and the water behind the pump drains out of the two drain plugs.
Mind you I haven't had to deal with plug wire shielding, but I have done this on jack stands without ramps on several C3s. The shielding will make things difficult.
Mind you I haven't had to deal with plug wire shielding, but I have done this on jack stands without ramps on several C3s. The shielding will make things difficult.
Race Director
Joined: Mar 2006
Posts: 14,112
Likes: 28
From: Florida
No,
The ign shielding must come off.
Crud blocking the drain hole with plug removed
What was inside the block. Flush it out well before the new radiator or you will plug the radiator.
The ign shielding must come off.
Crud blocking the drain hole with plug removed
What was inside the block. Flush it out well before the new radiator or you will plug the radiator.
Last edited by noonie; Dec 19, 2008 at 06:49 PM.