Cbest way to clean the water passages in a block, while still in the car?

I recently got my 41 ford running. It had sat for many years, but runs great. It has slowly stared running warmer and warmer. I drained the cooling system and a lot of dirt came out. I ran a flush through it, but I think it just loosened more up and it is clogging the radiator. I am going to pull the radiator and have it cleaned, but what about the block? I was going to use a pressure washer and blast through it...but does anyone have a better solution? I gotta get her back on the road for the flathead run next weekend!

 

That's a tough one Chris. You get alot of that out when you hottank a block, but in the car that's not an option. If you pulled the heads and the waterpumps you could go into the water passages with a high pressure steam cleaner pushing the crap out the front.

I would be carefull putting any kind of acid based solution. Cast iron is porous and rust has a way of pitting deep and worming it's way through. You just want to get the loose stuff. Once you get antifreeze in the rust will stop.

 

I'll try to find it (ford barn maybe) but I thought I remember something about vinegar.

 

I use to use a power flusher to clean the cooling systems on cars when I worked at a dealership. It worked pretty well. You might check with your radiator guy or with friends who have or work in shops.
It was a machine that you hooked to the cooling system and after draining the coolant out you ran cooling system cleaner though the engine with the machine which had a pulsating action.

 

Once you flush out your block and radiator put some stockings in the top hoses to catch the bigger bits of rust that keep blocking up your radiator.
Drive around for a day or two then pull the stockings out wash out the rust pieces then put them back in.
After a couple of months driving you will have caught most of the loose rust.
You might be able to get screen thats made for doing just this from your radiator shop.

 

take the radiator out & and run a hose thru it backwards,then put it on 2 saw horses & fill it with cheapo($1) lime & calcium remover from the "family dollar" store & let it sit!Then use a regular garden hose & run it thru the block backwards also till everything is out of it.THEN Fill the block somehow with the lime cleaner & let them both sit for a few hours.Flush it out again & after its all put back together fill the system with fresh water( no antifreeze) & add a box of baking soda(arm & hammer).Run the car for a week or so then drain everything , run a hose thru it quickly & then fill it with water/anti freeze.I've done this many time & it works great!!Takes alittle while but its worth it!saves alot of money.
JimV

 

Chris, if you can pull the water pumps and heads, it will make this job a lot easier. Use an assortment of long wire bristle brushes, jam them into the cooling passages from every angle while running a hose through them to carry the loosened rust/sand/etc out of the block. Works for me.

 

I'd be careful of running a pressure washer through the block, too much presure could cause gasket failure.

I like the idea of sticking socks in the hoses, washing them and puting them back on

 

I used vinegar on my 59ab. Be careful, flush with a lot of water and use the baking soda when done.

 

Never tried it but have heard Drano works??

 

Its more dirt then rust I think. When I pulled the radiator cap off the other day there was 2 inches of mud right under the cap. I scooped it out, did a chemical flush with something found at a auto parts store and filled her up. Now it is running hotter, it slowly heats up and will not cool no matter the speed...so I am guessing theres more dirt in the system plugging the radiator.

Im not worried about the radiator, ill have a shop clean it...but the block needs cleaned im sure! I like the suggestions so far, thanks everyone!

 

Also- what does the baking soda do??

 

Jimv up the way hit what I was going to say. I have used CLR in cooling systems a couple of times to good effect. I'm not as keen on using it in a radiator though, the real name brand stuff is a bit rough on non ferrous metal. Sounds like you might have a head gasket on the way out though...

 

Neutralizing the acid from the vinegar or what ever other caustic product you use.

Bobbyd

 

There is a great product called RMI that we use all the time in the shop. Works wonders.
http://rmisource.com/learn-more

With old rads, you can also get some muriatic acid from home depot and fill it up, slosh it around and rinse well. I dont think I would run that in the block though.

 

What works best to dissolve old crystalized antifreeze?

 

If it's an older radiator be carefull how you have it cleaned. If they hottank it there's a good chance it will come back leaking. Then they sting you for a core. I work at a deisel shop, and we use Simple Green to flush the systems. Of coarse there we are cleaning fuel or oil out of the cooling systems.

 

pull the water pumps off of it to start, then start flushing it out, i have a peice of 3/16 brake line about 30" long on the end of my blow gun, shove that in the front of the block with the water hose in the upper outlet, start blowing, it will free up and stuck junk, and make a mess! keep flushing and blowing and go till the water starts to get clean.

all that shit probably freed up and and clogged the rad, make sure the block is good and clean so you dont clog up the radiator again.

jeff

 

Dupont made a two part cleaner that worked really well but I haven't seen it anywhere for years.

You could try connecting the radiator hoses together, fill it with water and run it for a short time to circulate. Let it cool. Remove the hoses and flush the block with a garden hose. Then do the same using some type of cooling system flush. While you have the radiator out, fill the block with vinegar and let it sit for a day and flush with a garden hose again.

There was an adapter that fit on a garden hose that fit in radiator hoses up to 2 1/2" that we would put on the lower hose and let water flow through with the thermostat removed and the engine running. Then switch to the upper hose and back flush it.

 

Why do you think the head gasket is on it's way out? It's red dirt inside, I shinned a flashlight inside the radiator and I can see some a couple stink bugs too! She sure is dirty inside...

 

like thunderbird, and titus said this is the best way to do this. i made a scraper from a thin piece of sheet metal, and put a bend on the end, like a back scratcher.

 

OK guys, I took some of the advise here and did what I thought would work best. Thanks to everyone for the input! I ended up getting some vinegar and letting it sit in the block for half the day. Then, one side at a time I took the pump off and as Titus mentioned, I ran the hose down the water outlet and used a long piece of brake line attached to my air hose and blew...man Jeff, you were right that really got the stuff movin! Did that until the water was coming out clear. My radiator is still getting cleaned, but borrowed one from my Dad and put it back together tonight and drove it around. Seemed to be OK, but going to go on a longer drive tomorrow in the 90 degree heat!

Thanks again, Chris

 

Hi Chris...I would pull the heads and the water pumps ...I use 15" of old speedo cable in a drill the end you poke into the block get some plyers and fray the end so its got spikes and just guide it through the block and flush the residual rust particals out...use some old stockings for a couple of days in the top hoses to catch any crus that is still floating around....best of luck....Doug

 

let us know how you make out.
JimV

 

Awsome, glad it worked, when i ran the machine shop it was incredible how much crap id see built up in the bottom water passages of blocks, and you could really tell a motor that did use anti freeze in it!

jeff

 

you mentioned the long slow heat ups, and from your other threads on this car, I know that it sat for a very long time. Just my experiance with flatheads generally makes it a strong recipe for bad head gasket when water starts flowing again... Nothing more than that. Sounds like you've got it in hand though. Stinkbugs Eh?!

 

Maybe, I replaced one head gasket when I pulled the head...it was already loose when I bought the car. Someone unbolted it to get at stuck valves but never got the head off. It was a real chore but she finally came and I obviously replaced it I can see were that could be the case...I'm just hoping it was a clogged radiator! Sure was a lot of gunk in the block!!!

Oh, and a slick trick I did in case someone needs to do this...I used the upper hoses on the bottom outlets when I had it soaking. 39-41 have a long upper hose with a sharp 90 degree that dumps right into the head. Using that short 90 degree area to clap to the water pump sticks the long part of the hose strait up...above the head. So I just filled it until the vinegar was at the top of the head!

 

Been reading with interest. I have bought a new rad for my 40, and really don't want to fill it with crud from the old flattie. What Vinagar do you use, and do you dilute it?

 

You can use white vinegar. It doesn't need to be diluted at all. I've run it in my 39 for a week, then drained and flushed with baking soda. Plus, it's cheaap
Jim

 

Yeah, I went to the store and bought distilled Vinegar. You will need about 3 gallons.