Finally found time to get the boat on the water today. She started right up on the trailer, backed her off the trailer and idled around,a few times with a bit more gas while waiting on the person parking my trailer. All good, ran very smooth, picked up my passenger and we "idled out" once past the no wake zone, I gave her gas and she sputtered and died. I tried and tried to get her to start and nothing. Had my passenger prime the fuel bulb a few times and it started to fire a few times, but just wouldn't completely fire. Battery dies, I pull the cowl off the engine and the fuel filter is empty. I prime the bulb again and it fills up the filter. We get a tow back to shore, load her up and here I am....
We did some reading on the way back home and some things say replace the fuel lines, some say it could be the filter or even the primer bulb and of course a few say possibly a cracked diaphragm on the fuel filter. Fuel tank vent was also mentioned.
I'm guessing not a spark issue, but I realize it's a possibility and that's what the boat shop is thinking whilst talking over the phone. Worst case it goes to them on the 28th. Plugs I pulled out looked good and I will double check the new plugs that I put in last year that don't have much time on them, but I am pretty sure I checked last year and they looked good. Are NGK's OK? My friend said he read they weren't recommended for a 70hp Johnson....it was what I could get. The carbs have a weekend on them at best since a rebuild by me, but tuned by the shop. I'm also going to somewhat rule out fuel tank vent, primer and fuel line, because I have two tanks, both worked then neither worked. Brand new fuel filler cap on main tank with gauge and vent...spare tank is a 6 gallon metal style. I can't recall if I changed fuel filter, I remember buying one, but it didn't work as was wrong size. Can't recall if I bought another one, but I do recall thinking all was good there.
What I plan on doing is buying two new primer bulbs and new fuel line from tanks to the motor. Is there a quick release that can be bought to make syphoning the tanks quicker? I'm not talking about the connection from line to motor, I'm talking about something else inline. I'll also try to replace all the fuel line from the cowel inlets to the carb as well as the filter. If they aren't an issue now, I don't want them to be an issue later.
Since I'm leaning towards this being a fuel pump issue, if I pull apart the pump, is it easy to find a cracked diaghram? Is it better to rebuild my current pump or buy a new unit? I'm not sure if this motor has the ability to be an oil injection motor, but if so, I'd love to convert it back. I hate mixing the oil with the gas....not sure why!
Hope someone can provide some more answers. Also, can a fuel pump issue easily be diagnosed while on ears in the driveway?
