240 GLT saloon restoration project

[Stephen Edwin]

Originally Posted by Laird Scooby

.... saline solution......

Dave

In an amiable pedant mode.

Tautology alert. Surely saline is a solution.



Stephen



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[Juular]

Originally Posted by Laird Scooby

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Out of curiosity, have you heard of/used electrolytic derusting before? One of the side effects is that it actually plates good metal back on, useful where the metal is pitted but obviously it's only a small amount.



With "safety-critical" components it's advisable to put them in the oven on a low heat (~100C) for an hour or so to purge the hydrogen from the metal to eliminate hydrogen embrittlement. It's also good practice if painting it so the hydrogen doesn't cause micro-blisters as it escapes over time. Welding the item will also help purge the hydrogen from it as well. You can also copper-then-nickel plate any items for a durable, bright finish but it will need polishing to make it bright and shiny usually. Other electroplating methods are also possible.

I've been using Citric acid baths for smaller parts but have never tried electrolysis, due to lack of space / time / materials.

To be honest nothing off this car is very bad, surprisingly. A quick blast with the wire wheel on the grinder or drill, a thorough degreasing and a rough up with the power file or sandpaper, then 2-3 coats of hydrate 80 followed by 2 part epoxy mastic is my current strategy. Anything that is too heavily pitted or compromised gets either binned or cut and repaired.

Good to know about the heat. Thankfully almost everything has been blasted with a blowtorch or heat gun to remove the horrible bitumen underseal!

[Stephen Edwin]

Originally Posted by Laird Scooby

On a previous car, the outer sills weren't structural as there were 2 inner sills for rigidty. However the seat belt mounts on that car were shared by the seat mounting points, one on the inner-inner sill and another inside the B-pillar. Because that car had corrosion within 12" of at least one of those points, it failed on the outer sill. It had previously failed on a really rotten outer sill the other side and i had a new sill plus repairs to the outer-inner sill.
However this brings in more hypocracy and what i think are double-standards at times. That said the different construction of various cars means they have to draw a broad average line and include as many as are practical points to fail/pass a given vehicle on.

Dave.

This reminds me of some MOT results on my 240. It is not only strange regulations. There is also varied interpretation. The 240 estate notoriously has apparently superficial corrosion at the rear. I knew it goes deeper and I have had it sorted. However. A generally straightforward tester passed the car one year. I asked him about getting welding done. He said no need. Next year he failed the car. The next day two testers in another also respected garage passed the car, knowing of the failure.

Not exacly relevant to what you said. But there it is.

Stephen

[Laird Scooby]

Originally Posted by Stephen Edwin

Dave

In an amiable pedant mode.

Tautology alert. Surely saline is a solution.



Stephen



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From WIkipedia Stephen - "Saline (also known as saline solution) is a mixture of sodium chloride in water and has a number of uses in medicine."

https://en.wikipedia.org/wiki/Saline_(medicine)

Also from the OED aka dictionary.com :

A solution of any salt, usually an isotonic sodium chloride solution.salt solution

https://www.dictionary.com/browse/saline-solution?s=t

As such, either is acceptable and for the purposes of the context i used "saline solution" in, makes the flow of the words better.

Maybe i was unduly unkind to the late 70s Fiats as they weren't the only afflicted cars, many Lancias (not surprising as Fiat and Lancia were tied together then as they still are now) also suffered as did many 240s from the same time. The problem was poor quality Russian steel that had somehow found its way onto the general market.

[Juular]

Originally Posted by Stephen Edwin

Dave.

This reminds me of some MOT results on my 240. It is not only strange regulations. There is also varied interpretation. The 240 estate notoriously has apparently superficial corrosion at the rear. I knew it goes deeper and I have had it sorted. However. A generally straightforward tester passed the car one year. I asked him about getting welding done. He said no need. Next year he failed the car. The next day two testers in another also respected garage passed the car, knowing of the failure.

Not exacly relevant to what you said. But there it is.

Stephen

I've also had a car fairly recently pass an MOT with no advisories, only for the suspension to fail spectacularly due to corrosion a matter of days later. A visual inspection really doesn't catch things that may be hiding away behind other components or shields.



In this case the rear subframe failed at a section hidden under the fuel tank.

[Stephen Edwin]

....


Yes Dave .... BUT .... the clue is in "also known as" ....


Saline is a solution ... init .... if it were not it would surely I think be injurious to infuse ....


so it is a tautology .... but hey, my comment was and is declared amiable pedant mode.
This household has a medical sciences background ....


Stephen




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[Stephen Edwin]

Originally Posted by Juular

I've also had a car fairly recently pass an MOT with no advisories, only for the suspension to fail spectacularly due to corrosion a matter of days later. A visual inspection really doesn't catch things that may be hiding away behind other components or shields.

.......

In this case the rear subframe failed at a section hidden under the fuel tank.

OUCH !!!!!!


Stephen




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[Laird Scooby]

Originally Posted by Juular

I've been using Citric acid baths for smaller parts but have never tried electrolysis, due to lack of space / time / materials.

To be honest nothing off this car is very bad, surprisingly. A quick blast with the wire wheel on the grinder or drill, a thorough degreasing and a rough up with the power file or sandpaper, then 2-3 coats of hydrate 80 followed by 2 part epoxy mastic is my current strategy. Anything that is too heavily pitted or compromised gets either binned or cut and repaired.

Good to know about the heat. Thankfully almost everything has been blasted with a blowtorch or heat gun to remove the horrible bitumen underseal!

The one big problem with citric acid baths are they remove rust - the rust that was previously good metal. This results in thinning of the component.

The electrolysis method converts this rust back to good metal by deoxidising it. This makes the steel as thick (usually) as it was originally so restores the strength.

This is where the hydrogen embrittlement comes from as it removes the oxygen from the iron in the steel but replaces it with hydrogen and a ferric oxide compound which manifests as a brown scum on the workpiece and/or the surface and eventually sinks to the bottom of the tank.

That's why the component needs heating after the electrolysis to release the hydrogen. As for your painting methods

Electrolytic derusting takes very little time or cost. If you have a tub big enough for the components, you can do it easily. You'll need an "old skool" battery charger or a slave battery plus new style charger, a piece of scrap steel, water and a bag of washing soda/soda crystals, usually between £1.00-1.50 for a bag of about 1-1.5kg depending on brand and where bought.

Arrange the work piece in the tank so it is suspended, likewise with your piece(s) of scrap (sacrificial anodes) but place thse around the edge of the tank. Wire the anodes together and leave a tail of wire to connect to the +ve output of the charger.
Run another wire from the workpiece so the -ve from the charger can be connected.

Fill the tub up so the workpiece is covered with hot water, connect the charger and switch on. Add washing soda until the ammeter starts to move, indicating the process has started. I usually add about the same amount again and give it a gentle stir - this will usually cause a temporary surge in current - nothing to worry about as it will settle.

Leave it overnight, switch off and remove the workpiece then rinse in plain water. Inspect to ensure all is removed, if not put it back in the tank and power it up again and leave it another 24 hours. Giving the tank a stir when you put the work back in can also help move the last bits although i have heard of some people use fish tank pumps to move the water around and/or aerate it - even a heater has been used to not only move the water round (thermosyphon idea) but also to increase the reaction making it faster/more efficient.

The current will drop as the rust disappears and the anodes will become rusty - wire brushing or using another sacrificial anode in place of the workpiece and reversing the polarity of the charger will clean them again.

As you can see, it takes no more time (possibly less) than a citric acid bath and also strengthens the workpiece. It's particularly useful for cleaning rusted threads, eccentric adjusters and similar and won't remove any original plating. Probably cheaper than citric acid too!
Once drained and filtered, the solution can be used almost indefinitely as long as it's topped up to the level above the workpiece. Don't let the charger leads into the solution while removing rust, it will corrode the clips and wire on the charger!

[Juular]

A coat of H80 on the crossmember to be followed by 2 part epoxy.



And the brake line bracket. Had to make a new one.



A delivery arrived!



Bits and bobs got an acid bath.



Then dunked in strong tea - the tannic acid helps stop the flash rust.



And a quick blast of galv spray. Why not.



The brake discs also got a bath in acid as they are almost unused but had a layer of rust. I'm very pleased at how they came up and to be honest I think I will just reuse them.



Did a brake line cleanup. Are copper lines standard fit?









Regarding the brake octopus, is it worth removing and servicing this in any way or should I leave well alone? Bearing in mind I will be completely replacing all fluid.

Next up, calipers. All bleed screws came out bar one. I blobbed some copper grease around it to stop weld from sticking.



Then built up a nice big fat blobby weld.



Then hammered on a fluted socket and loosened it right off with the impact gun. This is a good go-to method for removing broken bolts.



The piston seals were rock hard and the pistons would not come out with any amount of compressed air. I had to resort to a grease gun.



The problem is once one side falls out, you no longer have a seal to pass the pressure to the opposing piston. So I had to make a tool to hold one piston on the cusp of the seal and provide space for the opposite one to push out.



I then had to blast a pressure washer jet through each port and through the caliper bridge to push all the grease out. Then the calipers soaked in hot degreaser to remove the remnants.

A bath in paint stripper is next.



After which the seals, boots, bleeders will be replaced and a coat of high temperature paint.

Next, sorting out the steering gear.



No leaks present whatsoever, I'm not replacing any seals. I just have to bend the locking tangs back.



I didn't bother messing with the track rods, I just chopped them off and fitted a track rod removal tool which spun them off without drama.





Then the rack is getting degunked and possibly a coat of paint since I'm here. Then new track rods and ends of course.

[Othen]

Originally Posted by Juular

Next up, calipers. All bleed screws came out bar one. I blobbed some copper grease around it to stop weld from sticking.



Then built up a nice big fat blobby weld.



Then hammered on a fluted socket and loosened it right off with the impact gun. This is a good go-to method for removing broken bolts.



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I really liked this method - well done.

Good write up, I'm really enjoying this thread.

Alan