bad 470 fuel pump, carb or dealer

[Todd Peterson]

I had the local marina repair my engine (water in oil) and valve job and a few other things. When I gave them the boat to work on, the engine started and ran great (water in oil, milky oil). After they completed the work on the engine they said it ran great.

I picked it up and worked on the floor for 3 weeks (stringers and floor). When my floor work was done I tried to start the engine and now very little gas is in the carb and it will not run. When I pump the throttle, some times gas may squirt into the carb barrel or it will just leak out of the orifice into the carb barrel. I can get it to run/fire when I pump enough gas using the throttle into the carb or on starter fluid. I do have spark, just not enough gas.

It is a 1984 470 mercruiser, 3.7L, 170 hp.

I looked at the fuel filter when it came back from the dealer and it is dirty with pin head size particles on it, maybe about 10%. I put the carb end of the copper fuel line in a plastic bottle and turned the engine over and just in a few revolutions, I had a half a cup of gas in the bottle.

I gave it back to the dealer and they said that I need a new fuel pump and a carb kit for $900.00. They told me that the fuel pump had no vacuum.

Can I still pump gas out of the fuel line into a bottle and have no vacuum?

I believe that proper care was not taken when they attached the fuel line to the carb and pushed junk into the carb and plugged the jets and now it is my problem. Can the fuel pump go bad and the carb need an overhaul just in three weeks, at the same time? Coincidence?

Any thoughts?

 

[abj87]

Re: bad 470 fuel pump, carb or dealer

After 25 years you are probibly due for a carb rebuild. I end up going through mine on my trucks and boats ever few years.

If you can replace the stringers and floor yourself i bet you can replace the fuel pump and rebuild the carb yourself. I did it a couple months back and its easy.

 

[Todd Peterson]

Re: bad 470 fuel pump, carb or dealer

Yes, I can do the fuel pump my self, the carb I will have a friend do. My big question is the dealer. I do not think that they are being truthful. I think that I am right with the fuel pump, that is works. I do not have the test equipment to check vacuum.

I have had great car dealers that will tell you what is wrong and fix or replace what is wrong and not use the shot gun approach and replace everything that is associated with the problem.

The question is, can I pump fuel out of the fuel pump and have no vacuum when testing? I do not know how to hook up a vacuum line to the pump to check this out. I have seen the thread on this subject, but I do not have the equipment.

 

[ne7800]

Re: bad 470 fuel pump, carb or dealer

i also have a 470 and strugled with a fuel starvation problem i added a in line filter $3 replaced the fuel pump with a electric one $52 (mine was bad) replaced the filter at the carb $1.50 with a paper one and did a carb kit $26 runs like a champ now

 

[JustJason]

Re: bad 470 fuel pump, carb or dealer

buy a compound gauge if you don't have the tools... i think they're only 25-30 bucks for a sears one.