fuel pump on mercruiser 360

H

h2ocwilly

Cadet
Joined
Jun 30, 2007
Messages
15
I'm trying to replace the mechanical fuel pump on this 82 mercruiser 360. It seems that this works on a push rod but I'm not sure. If it is a push rod what is the trick in pushing the push rod up so I can slip in the new fuel pump. There isn't a lot of room there so its a little tricky. Also there is a metal plate that is between the pump and the block, should I remove that to push up the rod? Help, this thing is wearing on my brain.:confused:
 
FreeBeeTony

FreeBeeTony

Captain
Joined
May 15, 2002
Messages
3,991
Re: fuel pump on mercruiser 360

Try globbing some whell bearing grease on the rod before you push it up......should hold it up long enough for you to install the pump.
 
Reel Poor

Reel Poor

Vice Admiral
Joined
Jan 29, 2005
Messages
5,522
Re: fuel pump on mercruiser 360

Using needle nose pliers of forceps push the rod up then install a long bolt in the hole shown in the pic below to hold the rod up while you replace the pump. Do Not Tighten The Bolt Any Tighter Than Required To Hold The Rod In Place, Finger Tight Is Usually Enough. Then be sure to remove the bolt before turning the engine and replace with the original bolt that was in the hole. Also before installing the long bolt be sure the rod is not on it's out stroke. It's driven by a came lobe and you need the rod recessed into it's bore as much as possible to ease the installation of the pump.

FuelPumpBolt.jpg
 
H

h2ocwilly

Cadet
Joined
Jun 30, 2007
Messages
15
Re: fuel pump on mercruiser 360

Thanks for the input, that helps a lot. There is one other thing that I was wondering about. This pump is a little different than the previous one as it had a build in water seperator on it but the system has been upgraded with a filter/water seperator so I ordered a pump without the seperator. Now this pump has an extra 1/4" bulbed fitting. I assume that this is a over flow so I ran it back to the tank. Would this be correct??
 
Don S

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: fuel pump on mercruiser 360

It's NOT an overflow and does not go back to the tank. It is a safety device tho, if the diaphram for the pump fails it pushes the gas out that fitting. On the carb or flame arrestor is a fitting on the newer models that you attach a clear hose to that goes to the pump. Then if it leaks, you know it because you can see gas in the hose, or if it's a bad enough leak, it makes the engine run real rich and you have to see what's going on.
 
H

h2ocwilly

Cadet
Joined
Jun 30, 2007
Messages
15
Re: fuel pump on mercruiser 360

OK Don Thanks. Now if that fitting is only in case the diaphram ruptures then running that line, in clear braided hose, shouldn't be a problem being I don't have a new carb?? I had an extra fitting on the tank that was plugged off so I figured that would be the best place to run that line.
 
Don S

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: fuel pump on mercruiser 360

I had an extra fitting on the tank that was plugged off so I figured that would be the best place to run that line
Click to expand...

Bad idea. When the tank is full, you will have gas in that line...... It's not fuel line. It needs to be done as I described above. It's just one of the rules of the game.
 
You must log in or register to reply here.
Top