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Engine guides and mods

Roadster AC Pipe Replacement

The Roadster has a nasty habit of snapping the air conditioning pipes.

Modification Details

The Roadster has a nasty habit of snapping the air conditioning pipes.
Smart took 2 attempt to sort this out, an inline clamp and redesigned hoses.

The clamp helps a bit but as you can see, this car had the clamp but the pipe still snapped.
The aluminium pipes generally snap where they connect to the main mounting blocks.

Although mine broke the thinner left hand pipe, it's usually the thicker right hand pipe that fails.

Unfortunately the pipes run down the back of the engine, so changing them is a bit of a job.

With the car in the air, look between the undertray and the engine. You'll see the other ends of the AC pipes.

The pipe connections are called spring locks...

They are simple and clever but an absolute pain in the tits to disconnect.

You'd do yourself a favour by spraying a bit of oil into it. It helps a bit when you use the disconnection tool.

I bought these AC spring lock disconnection tools. They were on eBay and cheap.

However, you only need 2 of them...

... a 5/8" and a 1/2".

All you do is clip it over...

...and pull it towards you.

What happens is an insert is pulled into the spring lock, moving the spring out of the way.

Once the tool is pulled into place, you should be able to separate the pipes by pulling them apart.
However, they rarely pull apart that easily. I found that cutting the pipe...

...allows you to twist the pipe as you pull.

This really does help and the pipes tend to separate far more easily.
As the pipe is already broken further up, you can't break it any more than it already is.

Clean up the inside of the remaining pipe. Don't use anything too abrasive.

Take a Torx 40 allen key tool and remove the bolt from the top of the engine.

It's awkward and tight but keep trying.

You may have smart's 1st fix for this problem. It's a clamp that joins the 2 pipes together.
It is supposed to reduce the vibration in the pipes which weakens the joint.

It doesn't necessarily work or this pipe wouldn't have snapped.

To remove the clamp, use a Torx 30 allen key tool to remove the screw.

The clamp can then be levered open and removed from the pipes.

To remove the damaged pipe and to fit the replacement, you need to lower the engine cradle.
Just tilting the engine is no good as the pipe goes between the firewall and the cradle.

With the engine cradle lowered, there is plenty of room to remove the old pipe and fit the new one.

Before pushing the new hose in place, spray some oil onto the rubber seals.

Put everything back and get the AC system re-gassed.

Won't They Just Snap Again?

Shouldn't do as smart redesigned the thicker pipe that usually causes the problem.
Instead of the aluminium pipe going into an L shape before changing into a flexible hose,
the new pipe is a short straight piece of aluminium and the L shaped part is now all flexible hose.

This drastically reduces the amount of vibrations passing to the join..

Updated Hose Part Numbers

Thick pipe = A 452 832 01 32 (0009481V004000000)
Thin pipe = A 452 832 00 23

Hose clamp for old style hoses

Clamp = 0004260V002000000
Screw = 0002415V000000000

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