How to check fuel pump

[Oregonbythesea]

I am fairly certain that my fuel pump is not working properly. What I don't know is how to check it to confirm it isn't right. I removed it and took it apart but don't know what I am looking for. Can anyone tell me if the rubber diaphragm/gaskets can go bad just by age? Thanks.

 

[Barnacle_Bill]

Re: How to check fuel pump

They certainly can. Don't put it back together with the old parts. Get a kit from Merc. They are about $20

 

[Crazyman1225]

Re: How to check fuel pump

Of course they can go bad with age, just like everything else. You can look for holes, and tears in them. But would advise just putting it back together.Get a rebuild kit and do it. Eliminates the chance of missing something that can't be seen, and having to pull it again.

 

[jerryjerry05]

Re: How to check fuel pump

Why?? What's it doing?Ethanol is a big problem.
Compression/spark ok?J

 

[mikeneal]

Re: How to check fuel pump

If it is apart def replace the parts, they are cheap enough and do go bad.

 

[j_martin]

Re: How to check fuel pump

To answer the original question, you can hook a pressure gauge (15 psi is about right for a carburetor system) into the fuel line or rail.

edit: 15 psi gauge, expect about 6-7 pressure.

It's about the only definitive way to debug an intermittent problem.

hope it helps
john

 

[hkeiner]

Re: How to check fuel pump

As suggested by j_Martin, using a gauge is a very good way to determine if the fuel pump is working OK. The below linked Mercury's Service Advisory describes how to test the fuel pump, as well as how to test for other possible causes for insufficent fuel getting to the motor.

This guide is for testing the fuel system on a running motor. If you have the fuel pump already removed, the best thing to do is rebuild the pump with new parts and then test it according to the guide after you have things put back together. Not much you can test with the fuel pump removed and in pieces.

http://forums.iboats.com/attachment.php?attachmentid=26607&d=1240244928

http://forums.iboats.com/attachment.php?attachmentid=26608&d=1240244937

http://forums.iboats.com/attachment.php?attachmentid=26609&d=1240244945

http://forums.iboats.com/attachment.php?attachmentid=26610&d=1240245079