78 Johnson fuel pump and spark plug questions

[28sstony]

Ive got a 78 150hp Johnson that Im going through before an annual fishing trip south. This boat gets used twice a year and I like to make sure its in tip top condition before my trip. Having heard a few horror storries about the newer ethanol fuels, I pulled off a carb to get a peek inside and in the process I broke off the stem to the upper fuel pump. Where can I get a new fuel pump, and is the upper any different from the lower pump??


I also pulled the plugs (Champ UL77V)'s and there seemed to be a fair amount of grit across the face of the plugs, is this normal?? I run 93 ocatane and Klotz oil, last fill up was in July if that matters.

 

[emdsapmgr]

Re: 78 Johnson fuel pump and spark plug questions

If you broke off the hose barb to the fuel pump inlet cap, that is replaceable by itself. The upper pump is different from the lower pump. Give your Bombardier dealer the original part number 388554. It's probably been superceded a few times, but should still be available. You might want to replace the plugs. Do you run a secondary inline fuel filter? (one of the round white plastic types.)

 

[28sstony]

Re: 78 Johnson fuel pump and spark plug questions

No seccondary filter, but Im thinking about adding one since I need to go ahead and replace the fuel lines to the carbs.

 

[tashasdaddy]

Re: 78 Johnson fuel pump and spark plug questions

do some reading here, especially ethanol. also decarb the motor.

 

[emdsapmgr]

Re: 78 Johnson fuel pump and spark plug questions

There is a screen inside the cap on the fuel pump, but it's not as good as an inline filter. Later models have one inside the cowling-standard. You can easily add one to the hose from the tank-it should keep debris out. I second a decarb process.

 

[ENSIGN]

Re: 78 Johnson fuel pump and spark plug questions

Use a water seperating filter insead of the inline type,it's well worth the extra expense