1989 4.3 mechanical fuel pump replacement

[gberling]

Engine number c393247. Is carter m60315 the right replacement for my engine. I noticed a little bit of oil in my clear overflow/vacuum line. A auto mechanic friend told me the fuel pump is failing. Replaced it once about 8 years ago. The boat dealer wanted $280 for a replacement part

 

[dubs283]

Unknown if part number is correct but will say if there is fluid in the overflow (yellow, plastic) line you'd best inspect what said fluid is

If it's fuel, yep time a replace the fuel pump. If only oil, may just need a new gasket

 

[itsathepete]

Carter specs that fuel pump for Mercruiser 4.3 from 1984-91, which likely is when they switched to electric pumps for fuel injection

Mechanical Fuel Pump

carterengineered.com

 

[dubs283]

Carter specs that fuel pump for Mercruiser 4.3 from 1984-91, which likely is when they switched to electric pumps for injection

Merc 4.3L with carb used electric fuel pumps for a bit as well, along with some 5.0 and 5.7

OP mentions the "overflow/vacuum line" which to me indicates a mechanical pump. You posted a link to a mechanical pump yet mention an electric?

FYI OP, the clear yellow line isn't a vacuum line, just an overflow. Pump pressure will be enough to indicate a diaphragm rupture

 

[gberling]

Thank you. Ordered the carter and new gaskets. Just rebuilt my 33 year old carb. It was pretty dirty

 

[itsathepete]

Merc 4.3L with carb used electric fuel pumps for a bit as well, along with some 5.0 and 5.7

OP mentions the "overflow/vacuum line" which to me indicates a mechanical pump. You posted a link to a mechanical pump yet mention an electric?

Agree he has a mechanical fuel pump. Only mentioned electric based on the 1991 end date of the mechanical fuel pump application.

 

[dubs283]

based on the 1991 end date of the mechanical fuel pump application.

Good call. 4.3 has gone thru some changes over the years.....

 

[Lou C]

I had the same issue had oil, not gas in that yellow hose. Replaced the pump anyway after 30 years because the rubber gaskets were looking really stiff & dried out. Replaced the tygon hose as well because the original was all stiff & hard to see thru.

 

[Lou C]

PS interesting to note there is a Mercruiser version of this pump with that small filter and the OMC/Volvo version that had no filter as these had the larger canister filters.

 

[dubs283]

PS interesting to note there is a Mercruiser version of this pump with that small filter and the OMC/Volvo version that had no filter as these had the larger canister filters.

An in line water sep filter would be appropriate in this situation

 

[gberling]

An in line water sep filter would be appropriate in this situation

Yes. Boat did not come with one. added one 8-10 years ago. I bought the boat new.

 

[dubs283]

I bought the boat new.

You bought new, keep up with your routine maintenance

 

[gberling]

You bought new, keep up with your routine maintenance

I always just sprayed car cleaner 2 times a year. This is my 2nd fuel pump. The rest of the engine, have done everything a few times. I am a total maintenance guy on everything I own. You can eat off any engine I maintain. I even wipe them down 2 times a year.