Starting Problem (Force 120)

[NFA]

Alright, thought I'd seen the end of this forum (or is it, "my problems with my engine..."), but lo and behold....

Been trying to start my engine over the last week and no luck. I have crank, good juice from the battery, but it won't fire. It will tease me with a quick fire and die, but nothing after that.

Basically when I go to fire it, I get a lot of cranking early on (from a fully charged battery), but no actual fire. I will try and try, then eventually let it sit, try again with choking it (as I usually do to start it), then again without choking it, etc. It won't start, and eventually I lose battery juice, and have to leave it until I can charge the batter again.

The engine has ran like a gem in the past, but I have had consistent starting problems over the past two years. When I do have it running, it runs like a dream. Throttle is good, linkage, steering, in and out of gear, idle, acceleration, etc. The engine runs very well, but the starting is a big problem.

What I've checked thus far...

- the battery (brand new as of this season), when I crank it, obviously the battery loses juice, eventually not having enough to sufficiently crank the fly wheel quick enough, I have gone back and recharged the battery and tried without any luck, also tried jumping the engine with my truck (truck to marine battery to engine)

- the spark plugs, also brand new as of this season, also pulled the plugs to check for spark, and there is plenty of spark when cranking it to start

- the starter, was refurbished, brushes cleaned out early on this season, and works like a gem, however when I lose battery power, I lose starter power

- the choke, seems to work when I push the key in, I have also had somebody manually choke it (moving the rod between the two carbs up and down), but still no luck

- the carbs, I sprayed a carb-cleaner, "de-fogger" mix into the carbs early on in the season, so I'm guessing the carbs are cleaned out

- the primer bulb, I've pulled the fuel line after the primer, primed it to see if it is pumping fuel in, and it is, no problem there, also when I go to prime it before trying to start it, the bulb is nice and tight, I've also had someone prime the bulb while cranking it to see if that would do it but no such luck

Other than that, I'm at a loss. My next guess would be the fuel pump. I do not know exactly where it is, is the fuel pump the same as the fuel filter, is it the same mechanism?

Any other ideas, tips on what to try, things to look for, and check over, would be greatly appreciated.

Thanks in advance everyone!



Scott

 

[eurolarva]

Re: Starting Problem (Force 120)

Take some pre mixed gas and shoot it into the carbs. Then manually close the choke butterflies and try the starter and see what happens. If you get a response from this try doing one carb at a time and see if it is better or worse. I know you are stuck between a rock and a hard place but you are going to kill that starter. Even though you just had it rebuilt it cant take that kind of punishment for long. They are basically designed to only have to be used for like 5 seconds on a cold start and maybe a second on a warm start. Continued grinding on it will wear it down fast.

On the carb issue if you can get the motor to start just fine by spraying only one carb with the premix the idle circuits in that carb are probably gummed up or clogged. Spraying carb cleaner in a carb pretty much does nothing. The carb will need to be taken apart and cleaned correctly with the carb cleaner a piece of wire and some compressed air.

 

[Frank Acampora]

Re: Starting Problem (Force 120)

Don't know what year you have, but some generalities may help.
FIRST: Assume nothing
Start with ignition Check each wire to be sure you are getting spark on ALL plugs. Also check to be sure the correct wires are on the correct plugs--top to bottom, 1,2,3,4.

Next go to fuel delivery. Just because the primer bulb gets hard does not necessarily mean that fuel has gotten into the carbs, and just spraying cleaner into them does not necessarily mean that they are clean. Before doing anything, remove the black plastic fuel pump inlet and screen to be sure the screen is not clogged. If the screen is clogged, the primer bulb will get hard but no fuel will get to the pump or carbs. This may solve the problem right then. If not:

Remove all plugs and into each cylinder squirt about a teaspoon of fuel/oil mix. Replace the plugs. The engine should now crank a little until it clears out enough to fire. It should fire and run for a few seconds.

Now squirt fuel into the carbs trying to get it back past the butterflies. Now try to start the engine. Again, it should behave as above.

If it starts and runs for the few seconds, then it is reasonable to assume that no gas is getting to the carbs. Since the primer bulb gets hard, lets eliminate the fuel pump for now. Remove the carbs, remove the fuel bowls, and remove the float. Clean any junk in the bowl and check to see if the inlet needles are able to move freely and not stuck to their seats. Check to see that the seats are clear and open and check to see that the float is not stuck in the up (closed) position.Also spray cleaner into the small holes above the butterflies and through the thin brass tube that goes from the fuel bowl to the top of the carb. This cleans out the low speed circuit. Turn in the low speed needles till lightly seated, counting the rotation. Careful! They may be less than one turn. Remove them and spray cleaner through those holes. replace the needles the correct amount of turns out from lightly seated

If everything is clean and functioning properly at the carbs, then work back to the fuel pump.

Try to use the same brand gasoline. Different brands use different additives and the mixture of two kinds can cause a jelly like or granular sediment that clogs filters, pumps, and carbs.