What is this part in my fuel line?

[John Emberton]

I want to do my own service on my Yanmar diesel this year. I got a Yanmar manual and understand what to do on the engine. But my question is if you follow the fuel line back towards the fuel tank there is a brass cylinder that looks like a fuel filter or water separator. Is this a standard piece on my 1981 boat and what is it and how do you service it?

 

[Ed Schenck]

Perko water separator.

This was a standard part. I wrote about this some years ago including a link to a picture. It is in the archives but I could not find it. I did find the Related Link to the same topic. I had to remove the unit from the boat and put it in a large vise and use a lot of leverage to get it apart. I found that the screen had deteriorated and caused part of my fuel problem. I didn't need it because a previous owner had installed a large Racor downstream of the Perko. So I took out the insides and then reinstalled it. This was easier than purchasing and installing a longer fuel line to reach the Racor.