Ignition or Fuel

[texsun]

Backed the boat into water, started up fine but didn't want to idle. I pushed throttle to about 2000rpm and proceeded to push it of the trailer and jump over the bow. Once in tried to get underway but it went dead. Started up again, but still wouldn't idle. Made my way past the No Wake Zone and tried to trottle up. At first the engine began to shake as if a bad miss-then it picked up rpm's only to die back down. Over the next 5 mins or so it ran bad as I described. However there was a point where the engine smoothed out and I ran 4500 for about a minute. When I pulled back the trottle to see if it would idle it still ran rough and would not get up to speed again.
Put it back on the trailer. Back to the house.
My first thought was Fuel problem. but after reading some other post I wonder if this is a coil issue.
I appreciate the Help.

 

[tommays]

Re: Ignition or Fuel

Missing a lot of info about what you have in there

Has it had any service ?


Tommays

 

[texsun]

Re: Ignition or Fuel

Missing a lot of info about what you have in there

Has it had any service ?


Tommays

 

[texsun]

Re: Ignition or Fuel

Boat is a 96 Larson 174sei w 3.0l VolvoPenta. I have kept it serviced although I did not change the plugs this year I did change the Distributor cap. Never have changed or cleaned the fuel separator.

Sorry for not mentioning my specs.

 

[tommays]

Re: Ignition or Fuel

I would start with the fuel filters NOT sure if the volvo has one inside the fuel pump

i got away with water in the fuel a long time until it got high enough in the tank to get sucked up all the time buy the pickup tube

I went through a LOT of filters till i sucked the water from the bottom of the tank

Tommays

 

[texsun]

Re: Ignition or Fuel

I would start with the fuel filters NOT sure if the volvo has one inside the fuel pump

i got away with water in the fuel a long time until it got high enough in the tank to get sucked up all the time buy the pickup tube

I went through a LOT of filters till i sucked the water from the bottom of the tank

Tommays

 

[texsun]

Re: Ignition or Fuel

Thanks Tom,

I looked at a diagram and it looks like in addition to the sediment bulb on the bottom of the fuel pump, it also has a filter where the fuel line couples to the carb. Can anyone tell me if there are any other filters?

Thanks Again

 

[Bondo]

Re: Ignition or Fuel

From your description,.......

It's a Fuel Issue............... No Doubt.......

 

[texsun]

Re: Ignition or Fuel

Thanks to all. I'll get the sedimant bulb off in the next day or two and loosen the connection at the carb to see if there is some kind of filter/strainer there.

I'll keep ya'll posted. I always appreciate the help!

 

[Don S]

Re: Ignition or Fuel

There is a filter in the inlet line of the carb, and there is another filter in the fuel pump.
Your best bet would be to buy an aftermarket (Racor is one) Gas filter/water seperator and install it between the tank and the fuel pump.
This will keep the dirt out of the fuel pump and carb, and will seperate the water out to a point. When there is too much water in the filter, it will get into the carb and cause corrosion.
Boats always have more water problems than cars. Since there are more ways for water to get into the tank.

 

[texsun]

Re: Ignition or Fuel

Good Morning!
Removed the fuel/water separater at the fuel pump and I would say it looked clean and had fuel in it. Dumped the bowl and looked closely, no water. Reinsalled. Went to the carb filter/strainer. Removed it and looked closely, no water - and it looked free of any dirt or foreign stuff. reinstalled it. My owners manual showed the reassembly order for both procedures, but it was kinda hard to tell exactly which way the filters acutally went. I "think" I got them back in the way they came out.
Pumped the throttle several times and hit the starter. It started for only a second and then died. Again..several pumps on the throttle..hit the starter..same thing...ran only for a second. I repeated this about 5 or 6 times and it never would start and run. I know after I "opened up" the system it probably lost it's prime - but I thought that given the number of times I attempted the start it would have drawn fuel up to the carb.
Should I pour gasoline into the carb and if so how much?

Thanks Again for the help!

 

[Don S]

Re: Ignition or Fuel

Removed the fuel/water separater at the fuel pump and I would say it looked clean and had fuel in it. Dumped the bowl and looked closely, no water.

If you are refering to the filter IN the fuel pump, it is NOT a water seperater, only a partical filter. You may also have problems in the boats fuel system. Try this:

http://www.iboats.com/bbboard/bbBoard.cgi?a=viewthread;fid=24;gtid=1107009

While your problem may be fuel related, there is nothing ruleing out an ignition problem. (Plugs, plug wires, cracked coil etc. ) It would sure be worth a check.

 

[texsun]

Re: Ignition or Fuel

Thanks for the link Don.
Does anybody have any thoughts about pouring gasoline in the carb to help the fuel system reprime? If so how much.

Thanks Again to everbody.

 

[texsun]

Re: Ignition or Fuel

Good Morning!
Last night I disconnected the fuel line from the output side of the fuel pump. Had my son roll the engine. Plenty of fuel coming from output. Reconnected that - and went to the inlet side of the carb, loosened the metal line, moved it to the side and rolled the engine again. Strong flow there. Please nobody strike a match! Just teasing-managed not to make a big mess. Ok Reconnected the line to the carb and tried to start it. It won't start. It hits a little but will not run. I can look in the carb and see fuel streaming as the throttle is pumped.

How do I check the choke to see if it's working properly?

It seems that I'm getting fuel where it needs to be-but maybe the choke is not working right.
I appreciate the help!

 

[Mahoney]

Re: Ignition or Fuel

Sounds like Don might have you lean back towards the ignition side of the equation.

Provided the fuel is flammable, you have done about exactly what you need to short of running the engine from a seperate container full of fresh gas. However even with old gas the engine should catch and run for a while, maybe rough, but it should run.

I don't know if the 96 uses an electronic ignition or not but if not for sure replace the points and condensor and set the dwell and timing.

Check the plugs and make sure they are getting spark. If you pull some plugs and they look all wet, I am guessing you are having an ignition problem. You have already confirmed you are squirting gas into the engine with the accelorator pump. No need to dump more gas in there until you are sure you are getting park on all cylinders. I know my V8 will run with a couple cylinders not firing, but I am guessing a couple cylinders not firing on a V6 might be a tough call for having it run.

Sounds like its just not igniting. Bring it down to basics. Air, Fuel, Spark.

 

[Mahoney]

Re: Ignition or Fuel

Oh, just a minute. I did something like this once and kicked myself after replacing the distibutor cap. A new Distributor cap will come with a rotor.

Well I spaced it and actually forgot to put the rotor back in, Doh! this can't be your issue as you said it would run for a sec. I would double check that the rotor is pointing at Cylinder 1's plug contact during its TDC. never hurts to triple check the plug firing order and wiring too, thats so easy to mix up back there.

 

[Don S]

Re: Ignition or Fuel

It's an electric choke, if it's cold, it should be closed. If you leave the ignition on, it should open in a minute or 2..
Are you sure you are getting a good strong blue spark at the plugs? If not, you can pump gas into it all day long and it won't start.
You may also have flooded it. Pull the plugs and see if they are wet with gas.

 

[Mahoney]

Re: Ignition or Fuel

I was just going to mention that Don, I had the same thing just happen this spring. Ran fine one time out, got it back and it developed the same symptoms he is describing.

My problem was the float needle valve was hung up so it was just dumping fuel into the carb as soon as I started cranking.

If you can confirm what Don suggested that you are getting strong spark to all cylinders, check that you are not actually flooding it.

 

[texsun]

Re: Ignition or Fuel

Good Morning!
Didn't get to do any work last night, but I got new NGK's yesterday in the event I find bad plugs.
Please tell me the best way to check the spark at each cylinder. I've only performed this operation on motorcyles and lawnmowers - where it is easy find a good ground and easy to turn the engine. Do I just remove the plug and ground it to the block and have someone roll the engine?

Thanks Again

 

[Mahoney]

Re: Ignition or Fuel

Yup, that is the best way to do it and also see the strenghth of the spark. It also allows you to check the plug condition because you have to remove the plugs. Do it at dusk when its easier to see.

Sometimes I take a shortcut and use a timing light to check to see if they are all firing.

Again if it all checks out, crank the engine with the flame arrestor off(fire extinguisher handy just in case) leaving in neutral so throttle plates arent open. shut down and immediately check down the carb. Do you see puddles of gas?

Just don't rule out the fact you could be flooding it as well, this would prolly be evident when you start removing plugs though.