1969 Mercury 7.5 Fuel Pump . . .

[tpenfield]

My outboard was seeming a little wimpy lately, so I pulled the cowl to check things out, etc. Noticed that the fuel pump was spitting fuel & exhaust gases from the lower aft facing corner. I am figuring that this would mean the diaphragm has ruptured. So, looks like I'll need to rebuild the pump.

All the 4 screws seemed to be tight, so I am figuring it is the diaphragm . . . probably just happened within the last couple of outings. I'm surprised that I did not see a sheen on the water from the fuel leak.

Advice, thoughts on the fuel pump???

 

[achris]

Re: 1969 Mercury 7.5 Fuel Pump . . .

Hi Ted,

Almost moved this thread to the Mercruiser section.. :lol:

Welcome to the dark side

Fuel pump diaphragm kit still available, part # -53245A1, as is the entire pump if it breaks....

Cheers.

 

[tpenfield]

Re: 1969 Mercury 7.5 Fuel Pump . . .

Yup, outboard . . .

It is for the dinghy . . . got tired of rowing.

achris - I notice that you are a Moderator. Recent addition? Very nice, Congrats.

 

[achris]

Re: 1969 Mercury 7.5 Fuel Pump . . .

Yup, outboard . . .

It is for the dinghy . . . got tired of rowing.

achris - I notice that you are a Moderator. Recent addition? Very nice, Congrats.

4 days and 1 hour..

Thank you.

 

[tpenfield]

Re: 1969 Mercury 7.5 Fuel Pump . . .

Quick update . . . I wrapped some electrical tape around the perimeter of the pump, just to prevent it from leaking. It seemed to work OK for the short trip out to the mooring.

Since the boat and dinghy will be coming out of the water next week, I'll have time to rebuild the pump over the winter.

 

[achris]

Re: 1969 Mercury 7.5 Fuel Pump . . .

:thumb:
(Bit early for you isn't it?)

 

[tpenfield]

Re: 1969 Mercury 7.5 Fuel Pump . . .

:thumb:
(Bit early for you isn't it?)

somebody has to wake up the rooster

 

[tpenfield]

Re: 1969 Mercury 7.5 Fuel Pump . . .

Quick update . . . I wrapped some electrical tape around the perimeter of the pump, just to prevent it from leaking. It seemed to work OK for the short trip out to the mooring.

Since the boat and dinghy will be coming out of the water next week, I'll have time to rebuild the pump over the winter.

A quick update, since I like to post the resolutions to the problems that I encounter . . .

I have the engine back at my home and have taken the fuel pump apart.


I found a crack in the diaphragm as show in the picture below. I was expecting to find a hole in the diaphragm, based on the problem that I observed with the motor during the season. So, it is always nice to actually find what you suspect.



I have ordered a rebuild kit for the fuel pump. So, hopefully I will have worked through most of the 'age' issues with the outboard and next season will be more trouble free.

 

[tpenfield]

Re: 1969 Mercury 7.5 Fuel Pump . . .

All set. . .

I installed the new fuel pump diaphragm and check valves, then put it all back together. I had to tighten a few of the carburetor bowl bolts as the carb was leaking a bit.

Then for the test run, the engine holds an idle pretty well, which it was not doing prior to the fuel pump work. :thumb:

 

[bgc]

Re: 1969 Mercury 7.5 Fuel Pump . . .

Very nice work!