Was This Block Cleaned Before Assembly??
Thread Starter
Melting Slicks
Joined: Apr 2000
Posts: 2,145
Likes: 1
From: Ft. Walton Beach, Fl USA
Was This Block Cleaned Before Assembly??
Does it look like this block was hot tanked or otherwise cleaned internally before assembly? There is alot of rust/scale in the water passages. I don't remember the shortblock I bought several years ago looking this nasty inside.
Drifting
Joined: Sep 2004
Posts: 1,959
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From: North Bend Ohio
Hot tanking is a chemical cleaning process where the block , heads and intake manifold (and just about whatever else you want) is immersed in a tank of cleaning solvents and boiled. To do a really good job you let them cook it all weekend. By the way you need to take out all soft metal (cam bearings, freeze plugs) because this process will dissolve them.
BigBlockk
Later.....
BigBlockk
Later.....
Le Mans Master
Joined: Nov 2004
Posts: 6,128
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From: North Alabama
when my block was hot tanked then bored...it started developing surface rust in the lifter valley area and a few other spots before I decided to mist it with WD-40 while the build was taking place. Hot tanking will take ALL the oil residue off the cast iron and things will start to rust if not oiled. Doesn't confirm your block was hot tanked though...just MO
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Joe Kucinski
Senior Member since 1492
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From: Just because I'm paranoid doesn't mean people aren't out to get me...
St. Jude Donor '09
Mine was tanked (dipped) then washed among other things. The inside looked like the pic(surface rust). The external areas I had to immedicately coat with WD-40 until I was ready for paint.
I don't see how the internal (inside the block)surface rusting can be prevented.
Here's my block the day I brought it home.
I don't see how the internal (inside the block)surface rusting can be prevented.
Here's my block the day I brought it home.
Last edited by Jughead; May 3, 2005 at 06:05 AM.
Race Director
Joined: Sep 2004
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From: Arlington Va Current ride 04 vert, previous vettes: 69 vert, 77 resto mod
Originally Posted by Carl Granquist
Let me ask this: I have a small radiator leak and am getting ready to add "Bar's Leaks" radiator stop leak. Will I end up with scale and residue like this that's harmful?
no not scale and rust, just lumpy gooey crude.....and a heaster core that doesn't flow so well (maybe not a bad thing).....don't do it.....have it fixed....
Race Director
Joined: Apr 2000
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
That's as good as it gets. If you are taking that motor apart for inspection, might as well take it down to bare block and check main and rod clearances and cylinder bore size, taper roundness etc. Visual inspection will pick up the obvious but you need to measure all this stuff then you will know what you are dealing with and you will know the the torque settings are correct when you assemble. 
Last edited by MotorHead; May 3, 2005 at 08:24 AM.
Race Director
Joined: Nov 2000
Posts: 11,872
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From: Waterloo ontario Canada
Hot tanking is not what it use to be. The use of costic solutions due to pollution is a thing of the past here. They use a much milder solution, friendly to the environment and a large industrial dish washer. It doesn't do a good job on the internal water passages.
Le Mans Master
Joined: Mar 2002
Posts: 7,456
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From: Coming home from Luckenbach Texas
Originally Posted by Carl Granquist
Let me ask this: I have a small radiator leak and am getting ready to add "Bar's Leaks" radiator stop leak. Will I end up with scale and residue like this that's harmful?
Safety Car
Joined: Oct 1999
Posts: 4,101
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From: NorCal
The only way to really get the rusty crud out is media blasting. Our caustic soda hot tank does a great job, but rust is rust and it won't get rid of it entirely, just the loose stuff. I don't worry about it, I just use a quality antifreeze with a bit of soluable oil mixed in, and then change it at least annually.
Hans
Hans
Le Mans Master
Joined: Apr 1999
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From: Raleigh North Carolina
Originally Posted by bobs77vet
no not scale and rust, just lumpy gooey crude.....and a heaster core that doesn't flow so well (maybe not a bad thing).....don't do it.....have it fixed....
Race Director
Joined: Apr 1999
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From: Beverly Hills/Pine Ridge Florida
Originally Posted by norvalwilhelm
Hot tanking is not what it use to be. The use of costic solutions due to pollution is a thing of the past here. They use a much milder solution, friendly to the environment and a large industrial dish washer. It doesn't do a good job on the internal water passages.
In Maryland, with the EPA and MOSH (MD Occ. Safety/Health), hot tanking is a thing of the past. Used to use caustic lye. Now, every shop I've seen uses the large "industrial size" dishwasher. Chuck
Melting Slicks
Joined: Jan 2003
Posts: 2,804
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From: OKC Oklahoma
When I got my 400 back from the machine shop, i was less than happy. I told them that I definately wanted it hot tanked, but it only looked like they washed the outside of the block. They said, that's the best you get these days, but he didn't really go into detail. Anyway, I had it acid dipped too and it still didn't look good. There is still alot of rust crud in the water passages. I sprayed PB Blaster in there and used a wire brush where I could. I thought about media blasting it, but didn't want to keep dumping money into it. I'll just run some radiator flush when I get it all back together.
Drifting
Joined: Jan 2001
Posts: 1,347
Likes: 4
From: Slidell La
Bare iron that has been stripped of any coating will rust with a power coat very quickly. This should not be an issue. Even if it was "Hot tanked" the rust will form very quickly. I would not expect this to be an issue. When you add coolant the rust protection will stop further problems. So now.. finish it,, add water, and lets go to the track. 99 Nassau Blue