Volvo Penta MD2020 Exhaust Elbow cleaning

[mnrkks]

Hello,

I would like to clean my exhaust elbow in my engine Volvo Penta Md2020d. What would you suggest for a safest & easiest way to clean it?

The new one price is around 370 euros and mine is not that blocked. So I prefer to clean it without damaging it.

Thanks for you suggestions.

Onur

 

[Never Grumble]

Someone will be along to give you a range of solutions from brick acid to Rydlyme. Whether it works or not I have no idea, I stuck mine in the bin and bought a new one.

Volvo Penta MD2020 Stainless steel exhaust outlet kit

 

[vyv_cox]

The current long thread and many previous ones suggest that the deposits are the usual mixture of carbonates. These are readily removed by hydrochloric acid, Rydlyme and brick acid being examples of this. Attacking the deposit with a screwdriver often results in a hole punched through the cast iron. Patience is a virtue here.

 

[Neeves]

I have used hydrochloric acid in a plastic bucket. Its a nasty process, wear gloves, and something to protect your eyes. Keep pets and children at a distance. I simply soak overnight. I have found I can only do this once - the second time the corrosion is significant and the acid simply corrodes a hole through the casting. If your blocking is minor then you would not need to leave for so long in the acid. I can buy fairly concentrated acid here - we have no restrictions on sales. You need to find a way of disposing of the spent acid.

Vyv says the deposits are readily removed - once you submerge the acid does the work - but it might take time. The deposit cannot be carbon (though there is a lot of carbon there, as carbon is inert in acid). As Vyv says they are salts of calcium and magnesium (of which seawater carries much) - mixed with carbon.

I have found the accretions to be hard.

Read the other threads - I think there are now 2 on exhaust elbows, they are primarily focussed at stainless elbows which may, or may not, show advantage over the cast elbow. My new elbow, 304, should be with me next week or early the following week and I'll make an update then on what it looks like - you then need to wait at least 12 months to find out if it offers any technical advantage! Commercially its cheaper than a cast elbow - I'll provide full detail on prices when I receive the elbow.

Jonathan

 

[PetiteFleur]

Don't try removing the deposits with a screwdriver - it'll go through the casting as happened with me!

 

[Moodysailor]

I would be very careful trying to clean these. As they are an iron casting, the thickness of the material tends to decrease over time. When I was in the trade at a VP dealer we always had a run on these around lift-in time from the few that had found they were too thin after cleaning, or punched a hole in them as mentioned above.
Personally, I would just leave it and replace it once it narrows the outflow to about 50% diameter.