Question regarding Engine Block - After Hot Tank, Caustic Solution Bath and Pressurized Air

[gn87man]

Has anyone ever seen a block become extremely brittle and flake off into a powder while attempting to machine the block?

Here is my situation...

My engine builder informed me that the block has been dipped in the hot tank and into the caustic solution bath.

The engine was also pressure blasted with high pressure air.

The problem is not rust. It seems to be that the block is basically corroded to the point that it is disintegrating.

In the pictures, on the bottom of the block, where the oil pan gasket is attached, it looks as if part of the oil pan gasket needs to be removed. However, that is not the case. This is the actual block flaking off. The metal is physically flaking off. This is shown in several areas of the block. Especially on the top side of the block on the slanted wall that comes down to the valve ports. The engine builder took a regular screwdriver and gently tapped it against this top face of the block and the metal just started flaking off into powder. It is the strangest thing I have ever seen.

These imperfections were unable to be detected until after the block was hot tanked and dipped in the caustic solution bath and blasted with high pressure air.

I have no idea what might have caused the issue.

Please let me know if anyone has ever experienced these issues with a block. If so, what was the main cause?

Could it possibly be caused by the block sitting in storage, near the coast, for several years (exposed to a saltwater environment)?

Or possibly the block being left in the caustic solution bath or hot tank for too long?

Please see attached pictures.

Thank you!

 

[turbofrank]

After a block is cleaned and dipped all areas need coating immediately. That block appears to have been neglected left naked to atmosphere. Maybe your shop used wrong chemical. I would find another shop to cleanup and dress block.

 

[BEATAV8]

Interesting....

google chemical reactions of iron. there are a few possibilities. depends upon what was in that solution.

block looks like its toast from here... too much damage.

 

[SCOOBY DOO]

I worked at the largest machine shop in Toronto. Blocks would be placed in the 'Typhoon' which was had caustic acid blasted at it from all angles while it spun. We'd immediately wash the block...dry it...and then mist it with an oil/varsol solution so as not to rust. That block looks like it's been left to the elements after it's 'bath'.

 

[NY Twin Turbo]

I would scrap that block for sure.

 

[~JM~]

You might research "Caustic Embrittlement".

Try to find a machine shop that has the equipment to Bake & Shot-Peen blocks for the future.

 

[hensleyt]

In the 70s that's all we used ,but we just used a garden hose to wash it off.
That looks like a block that had been laying around,sad 109 blocks are getting hard to find.

 

[Gene Van Horn]

That one is toast dude. Do waste anymore time on it. There is a couple for sale here. 3 or 400 is the going rate

 

[PSID6]

Has anyone ever seen a block become extremely brittle and flake off into a powder while attempting to machine the block?

Here is my situation...

My engine builder informed me that the block has been dipped in the hot tank and into the caustic solution bath.

The engine was also pressure blasted with high pressure air.

The problem is not rust. It seems to be that the block is basically corroded to the point that it is disintegrating.

In the pictures, on the bottom of the block, where the oil pan gasket is attached, it looks as if part of the oil pan gasket needs to be removed. However, that is not the case. This is the actual block flaking off. The metal is physically flaking off. This is shown in several areas of the block. Especially on the top side of the block on the slanted wall that comes down to the valve ports. The engine builder took a regular screwdriver and gently tapped it against this top face of the block and the metal just started flaking off into powder. It is the strangest thing I have ever seen.

These imperfections were unable to be detected until after the block was hot tanked and dipped in the caustic solution bath and blasted with high pressure air.

I have no idea what might have caused the issue.

Please let me know if anyone has ever experienced these issues with a block. If so, what was the main cause?

Could it possibly be caused by the block sitting in storage, near the coast, for several years (exposed to a saltwater environment)?

Or possibly the block being left in the caustic solution bath or hot tank for too long?

Please see attached pictures.

Thank you!

View attachment 295958 View attachment 295959 View attachment 295960 View attachment 295961 View attachment 295962 View attachment 295963 View attachment 295964 View attachment 295965 View attachment 295966 View attachment 295967

I had a similar situation but it was internal within the water jackets of a 3.1 v6 in a lumina I once owned. I purchased it down south where it is common to use straight water in the cooling system. Well the car sat for many months without being driven until I started using it as a daily driver. Shortly after the car started over heating, so I decided to change to water pump and and flush the coolant system. Well when I pulled the hose I saw solid orange fluid !!! The block was literally falling apart from the inside out it was so corroded it was at a point of no return. Pulled the water pump and flakes of cast iron where every where. Two radiators and three water pumps later I had to throw in the towel.

 

[gn87man]

Thank you all for your feedback!

Looks like it's time to find another block.

 

[TTipe]

Has anyone ever seen a block become extremely brittle and flake off into a powder while attempting to machine the block?

Here is my situation...

My engine builder informed me that the block has been dipped in the hot tank and into the caustic solution bath.

The engine was also pressure blasted with high pressure air.

The problem is not rust. It seems to be that the block is basically corroded to the point that it is disintegrating.

In the pictures, on the bottom of the block, where the oil pan gasket is attached, it looks as if part of the oil pan gasket needs to be removed. However, that is not the case. This is the actual block flaking off. The metal is physically flaking off. This is shown in several areas of the block. Especially on the top side of the block on the slanted wall that comes down to the valve ports. The engine builder took a regular screwdriver and gently tapped it against this top face of the block and the metal just started flaking off into powder. It is the strangest thing I have ever seen.

These imperfections were unable to be detected until after the block was hot tanked and dipped in the caustic solution bath and blasted with high pressure air.

I have no idea what might have caused the issue.

Please let me know if anyone has ever experienced these issues with a block. If so, what was the main cause?

Could it possibly be caused by the block sitting in storage, near the coast, for several years (exposed to a saltwater environment)?

Or possibly the block being left in the caustic solution bath or hot tank for too long?

Please see attached pictures.

Thank you!

View attachment 295958 View attachment 295959 View attachment 295960 View attachment 295961 View attachment 295962 View attachment 295963 View attachment 295964 View attachment 295965 View attachment 295966 View attachment 295967

Looks like salt in the air from salt water. Marine engines (for ocean use ) require different metallurgy.

 

[TURBOELKY]

Good lord

 

[Buick Mark]

Its poop, all the machined surfaces are falling apart

 

[45583ho]

start with another block, friend of mine had small cracks between the water jackets and decided to use, went kaput after 1 winter.

 

[gn87man]

start with another block, friend of mine had small cracks between the water jackets and decided to use, went kaput after 1 winter.

Will do. Good to know. Thank you!