Fuel pump failure?

boozer1966

Petty Officer 2nd Class
Joined
May 7, 2012
Messages
125
Mercruiser 140, Alpha MR, serial #6853440. Fuel pump is three years old. Gave no warning signs and just quit working. Is that normal? Any recommendations other than replacing with stock? Electric?
 

havoc_squad

Senior Chief Petty Officer
Joined
Mar 5, 2011
Messages
693
Re: Fuel pump failure?

I'm not a fan of electric fuel pumps being added onto an engine built for mechanical fuel pump, because they require a number of items to work right electrically before the fuel pump will turn/stay on.

What did you do step by step to diagnose it as a fuel pump issue?
 

achris

More fish than mountain goat
Joined
May 19, 2004
Messages
27,468
Re: Fuel pump failure?

Agree you ^... Do you know what the new (3 year old) pump was, brand? You should get a lot longer out of a pump than that, unless it's a cheap Chinese.

Chris....
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
70,465
Re: Fuel pump failure?

Mercruiser 140, Alpha MR, serial #6853440. Fuel pump is three years old. Gave no warning signs and just quit working. Is that normal? Any recommendations other than replacing with stock? Electric?

Ayuh,.... How much crud, 'n water is comin' from the tank,..??

Do ya have a canister type fuel filter plumbed in, 'tween the tank, 'n pump,..??

A restriction, up-stream, will cause the pump to work harder than necessary,...

Crud, will Destroy the pump,...
 

boozer1966

Petty Officer 2nd Class
Joined
May 7, 2012
Messages
125
Re: Fuel pump failure?

As far as diagnosing the pump as the culprit, the boat was running well, I stopped for an hour or so, just long enough to load up a weekend's worth of camping gear and my pregnant wife. Engine started with no problem and we pulled away from shore and it quit. It ran about long enough to burn all the fuel out of the carb. I checked for fuel at the carb and had none. Nothing coming from the pump. I checked fuel to the pump and it was ok. I then checked the line to the tank and it was clear. I don't know what else it could be but the pump.

I did install a new fuel water canister type filter a few months ago. But I've never had any problems with crud coming from the tank.

Can I see anything definitively if I take the pump apart? It's a Sierra. 3 years old and never gave any signs of having any problems before this incident.
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
70,465
Re: Fuel pump failure?

As far as diagnosing the pump as the culprit, the boat was running well, I stopped for an hour or so, just long enough to load up a weekend's worth of camping gear and my pregnant wife. Engine started with no problem and we pulled away from shore and it quit. It ran about long enough to burn all the fuel out of the carb. I checked for fuel at the carb and had none. Nothing coming from the pump. I checked fuel to the pump and it was ok. I then checked the line to the tank and it was clear. I don't know what else it could be but the pump.

I did install a new fuel water canister type filter a few months ago. But I've never had any problems with crud coming from the tank.

Can I see anything definitively if I take the pump apart? It's a Sierra. 3 years old and never gave any signs of having any problems before this incident.

Ayuh,.... Water can just show up, at 'bout any time,...

Pull yer filter, 'n inspect it's Contents,...

The fuel pump may well have died, I'm just lookin' for the Reason it did,...
A fuel pump is nothin' but a couple of check-valves, 'n a diaphragm,...
A speck of crud can jam up a check-valve,...
A spot of water could corrode it,...
 
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