Have not yet pulled the two block plugs for coolant.....look like maybe 3/8 pipe. Am considering making a spray nozzle that would hit any mud residue from the sides and hopefully flush better. On this old beastie, have gotten a lot of brown mud with several flushes and want to do something with these drain areas. Has anyone tried to flush with pressure on theirs.....I think a bath would be in order. thanks
383 block flushing
- Thread starter 66furys
- Start date
On an engine with a rusty cooling system, often the block plugs are going to be seized in place. You can try cleaning the area around the plugs and hitting the threads with some good penetrating oil. My luck has usually been that the plugs are too corroded to move.
Dave
Dave
I see that these plugs are at least not like the one under the fuel pump. That buried plug was as tight as anything I have ever dealt with....but finally moved. Have not tried one of these yet. But, want to make a nozzle of copper tube that will spray 90 degrees to move the sludge.....but just thinking at this point.
use a 6 point socket on the block plugs. Yes the penetrant seal is good. use some real penetrant, no "WD40”
It might work, it might not. I’ve found it’s better off removing the freeze plugs and manual agitation to remove any crud in there. Harder to do in the car. Remove starter for the left rear. Both front are behind the mount brackets.
It might work, it might not. I’ve found it’s better off removing the freeze plugs and manual agitation to remove any crud in there. Harder to do in the car. Remove starter for the left rear. Both front are behind the mount brackets.
agree best plan would be to remove the freeze plugs, not really hard to R&R if you have decent access.....but not here, I think. Sooooo, I am scratching the old bean as to how to best get some benefit from the block drain. And, my current thought is to get some NPT fittings with barbs, install, add hose to up side and add at least a quart of the cheapie toilet bowl cleaner, which is hydrogen chloride. I have used this in rusty gas tanks on bikes before and it works great. Fill tank fully and let stand overnite and voila....pretty good looking steel under the rust. So, I will add some into the block recesses, let sit and flush. We will see if I can manage this plan.
Put car on ramps and crawled under. Plug tight but not bad. Found a crust inder the plug about 1/8 thick addressed with screwdriver and hammer. Clear water, which is what I have in it now, came out. Msd about just over 2 quarts....my big drain pan has my graduations but just rough. But, I am happy as I can be with this....obviously the lower areas around the cylinders are open......no more chems at this time. Yeee ha
If you want to use a cleaner then get the best. This cleans out the rusty color real well. I’ve used in on many cars. Be sure to flush out the antifreeze very well before adding this.
Summit Racing SUM-TC001 Summit Racing™ EVAPO-RUST THERMOCURE | Summit Racing
I still think it’s best to manually remove the solid crud pieces first. There should be one freeze plug on each side you can get to. Remove the starter, that’s the easier one to get at. How will you get the loose crud out those small threaded plug holes?
Summit Racing SUM-TC001 Summit Racing™ EVAPO-RUST THERMOCURE | Summit Racing
Summit Racing SUM-TC001 Summit Racing™ EVAPO-RUST THERMOCURE | Summit Racing
I still think it’s best to manually remove the solid crud pieces first. There should be one freeze plug on each side you can get to. Remove the starter, that’s the easier one to get at. How will you get the loose crud out those small threaded plug holes?
Summit Racing SUM-TC001 Summit Racing™ EVAPO-RUST THERMOCURE | Summit Racing
^This^
Using that toilet bowl cleaner is asking for trouble. Hydrogen Chloride is pretty corrosive. I can see it taking out a couple old core plugs for one thing... and then it's hell on the radiator and heat core.
I've used Evapo-Rust rust remover and it only attacks the rust rather than the steel in the plugs and the brass, copper and solder in the radiator.
Personally, I would just do a reverse flush with no chemicals. Any of the "flushes" you did before looks like you didn't pop the drains out of the block...
I will check into the evapo rust, sounds intriguing. I saw the ref to the bowl cleaner years ago and have used it twice....works well on the MC tanks with nice shiny steel left over. This stuff is only 10% so not bad. But, will see what we see from Summit, one of my best sources. And yes, I had flused several times w/o pulling the side plugs until now....after worrying about the possibilities. But, with the amount of clean water I got out, I am very happy about this cavity at this point. Thanks for pointers, will do more work.
Yea, but a tank is a little different. No radiator and no half rusted out almost 60 year old core plugs.
Right, but I was only planning to add this thru the drain plug and about 2 qts that would not get to rad. Yes, would not want to get to copper or brass.....agree. But, after seeing what I found, not a problem at this time, I hope.
Dan Scully
Well-Known Member
If you can find one of these, they work great and washing soda does a good job on the clean out.
Baking soda and washing soda are two different things. You aren't baking bread.
73Coupe
Senior Member
I'd try regular Evap-o-rust or Rust-911 in there for a week, flush, and repeat.
The Therm-o-cure says that it's non-corrosive, this is a lie?
I know that the "regular" Evap-o-rust uses a chelation type of chemistry to separate the oxides from the metal, without acids. It turns black with use just as their coling system flush as told by reviewers on the Summit webpage.
Rust 911 is the better value though. A quart sells for about $40 including shipping, which makes 4 gallons, whereas Evap-o-rust sells for $35/gal and can't be diluted. You can buy Evap-o-rust at Harbour Junk, though.
The Therm-o-cure says that it's non-corrosive, this is a lie?
I know that the "regular" Evap-o-rust uses a chelation type of chemistry to separate the oxides from the metal, without acids. It turns black with use just as their coling system flush as told by reviewers on the Summit webpage.
Rust 911 is the better value though. A quart sells for about $40 including shipping, which makes 4 gallons, whereas Evap-o-rust sells for $35/gal and can't be diluted. You can buy Evap-o-rust at Harbour Junk, though.
RemCharger
Active Member
If you look at a diagram of the cooling system, you'll see where the gunk piles up
Right at the bottom of the rear cylinders.
Pull the rear frost plugs out. Get in there with a coat hanger to break it up. Hit the front heater hose nipple with water pressure.
When it's clear it's clean. Put in the frost plugs, or! , get those rubber plugs and you can do it again down the road
Right at the bottom of the rear cylinders.
Pull the rear frost plugs out. Get in there with a coat hanger to break it up. Hit the front heater hose nipple with water pressure.
When it's clear it's clean. Put in the frost plugs, or! , get those rubber plugs and you can do it again down the road
Thermocure is made for cooling systems and to be mixed with water. I’ve used it on 3 cars, it works excellent! One car was very rusty in the radiator, it was used in summer only with straight water, and it cleaned it up like it was never rusty inside. Years. Later the antifreeze is green with no brown residue inside like they will get sometimes.
It does not turn anything black, the rad is very clean and clear inside when done. USE THIS STUFF. It is made to mix with water, and works better by driving the car. Here is the instructions Below.
Regular evaporust is to be used full strength, not diluted. Cost is approx $30 per gallon. So the 3-4 gallons of the stuff. Why mess around with that? Is it made to be heated to 195 degrees? Just buy the product that is made for cooling systems.
I think I’ll order a six pack of this great product before they change the formula to something that doesn’t work.
It does not turn anything black, the rad is very clean and clear inside when done. USE THIS STUFF. It is made to mix with water, and works better by driving the car. Here is the instructions Below.
Regular evaporust is to be used full strength, not diluted. Cost is approx $30 per gallon. So the 3-4 gallons of the stuff. Why mess around with that? Is it made to be heated to 195 degrees? Just buy the product that is made for cooling systems.
I think I’ll order a six pack of this great product before they change the formula to something that doesn’t work.
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You guys are bakin me crazy......and John you are right. I have some of the A&H wash additive and did not connect dots. I also had guy come in years go to blast my car body with soda......I guess not the bakin type. I may order one of the products for later use if my system keeps coming up brown. Thanks for the pointers.
Gerald Morris
Senior Member
A lot of what you should do depends on 1.) the chemistry of what's in the cooling jacket now, and 2.) how much is in there. Have you actually looked inside the cooling jacket yet? That will help you a lot. If you use a good penetrant on the 3/8" NPT plugs, they should come out. Follow the directions for the penetrant scrupulously.
That may allow you to insert something small, but if much plugs that jacket, then removing an expansion plug will permit greater freedom of movement and allows more detritus a place to exit the jacket. I advise removing the rearmost pair, one on each side. You WILL have to remove the starter to get the driver side expansion plug out. Use 1 5/8" rubber bungs to replug the jacket temporarily, as serious block flushing requires more than one effort.
By removing those rear plugs, you permit all the detritus a low point to exit the block. Use a garden hose with good pressure at the heater hose input to the water pump, combined with the spout that also comes as part of the Prestone kit, and you can really hose out that cooling jacket! Keep it running until the water coming out of the spout is drinkable. Tastebuds make good chemical testers.
Removing expansion plugs also permits one to use drain snakes, small rotory wire brushes chucked to a flexible shaft, and such to enter the cooling jacket and work the deposits loose. THEN, after reducing the amount of impurities to just what is left in inaccessible regions, you can use the most appropriate chemical to remove the rest, flush the block with that garden hose, and when the water tastes good, then, and ONLY THEN, seal the expansion ports with brass plugs, and fill the cooling system with a good antifreeze mixture.
I deep clean my engines every other Fall, usually November, and flush them every November. This year will be a deep cleaning....
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