Engine woes...

[Pfu]

My boating woes continue. Between births, deaths and work there has been little time to play on the 2000 Gulfstream 232 with twin Yamaha 150’s. Last successful trip – only one all year – was taking my daughter-in-law and two grandsons around the bay for a quick ride. Boat ran well.

Boat sat for nearly two weeks and decided to try fishing on a Friday with my son and nephew. Got to the boat checked things out and ran engines on dock waiting for my son to arrive. Auxiliary tank was the primary at the time and showed ½ tank of fuel. Engines started right up and idled for approximately ten minutes and we were off. Got approximately ¾ mile from marina and one engine lost power and died. Second engine was running fine but dropped the rpms down to try restarting the other engine. No go. Then after about fifteen minutes the second engine stopped running as well. Dropped anchor to check things out.

Neither fuel ball felt like there was any fuel (remember gauge showed ½ tank) and couldn’t get any to the ball. Flipped fuel tanks knowing the true main was full. Was able to get fuel to the ball quickly and but could only get one engine to actually start (starboard which was the first to die on the trip) so puttered back to the dock.

The next day I went back to the marina and had to pump the port engine but both started up and ran fine for fifteen minutes. Due to time I was unable to take out for a run but felt good thinking the auxiliary tank gauge was bad and got seriously low with possible air in the line.

Went to the boat tonight, now a week later, to check the boat out and possibly put a few lines in the water. Both engines started right up with nothing but turning the keys. Ran fine at the dock for five minutes when the port engine died and then within five more minutes the starboard died as well. Seemed like fuel starvation again as both fuel balls felt empty. Got fuel into the starboard and she started up again but after five minutes died again. Could not get fuel to the port engine. Took the cowls off and the port engine had fuel in the clear filter but had air at the top. Starboard was the same but could not notice air in the filter cannister.

My frustrations peaked as never had these type of issue with the Mercruiser on previous boat but not ready to throw in the towel.

Now for my dumb questions.

• Fuel select valve decal shows front as main tank and rear as auxiliary tank. Both currently set to main but last time out was auxiliary. What bugs me is the decal almost appears as it is upside down meaning the selectors would be the opposite. Thoughts?
• Fuel separators were replaced last August. Fuel lines going from the separator to the selector valve appear old – possibly original – and if I am sucking in air somewhere assume they would need to be replaced. Most likely the same from the valve to the tanks but not sure how easy/difficult to swap out yet. No signs of fuel line size so if anyone knows please advise.
• Don’t have a portable fuel tank to connect to the ball as this appears as one possible test to eliminate some options. Might be able to get one via the marina. Is there something else fuel line related to check?
• Am I missing the obvious and should be looking elsewhere? From what I can see the fuel tank looks solid.

I just want to go fishing and get back to a normal life. The pandemic was easier than getting my Gulfstream to function as desired. I thank you all in advance for any advice.

 

[Pfu]

Some photos.

 

[SkunkBoat]

Venting? Although it both tanks...
Try removing the gas caps when it happens

 

[Pfu]

Venting. Although it both tanks...
Try removing the gas caps when it happens

I have removed gas caps and tried getting fuel to the fuel ball when it first started to have problems. Weird as one gets fuel but the other doesn’t.

 

[Halfhitch]

If you have squeeze ball pumps as old as the plumbing I see in the bilge, I would recommend installing new name brand squeeze balls first thing. Make sure the arrow is pointed up when trying to pump out the air.

The only way to make sure which tank you are using from with the valve in any certain position, is trace out the supply lines. There is no telling what someone has done in the past.

 

[Fishtales]

I'd run one off each to start. I'd be looking at the fuel lines and replacing to start.

 

[Pfu]

If you have squeeze ball pumps as old as the plumbing I see in the bilge, I would recommend installing new name brand squeeze balls first thing. Make sure the arrow is pointed up when trying to pump out the air.

The only way to make sure which tank you are using from with the valve in any certain position, is trace out the supply lines. There is no telling what someone has done in the past.

The squeeze balls are about two years old. I assume the part prior to the bulb is an electronic primer. Am I correct? Signs of when bad? Clogged?

 

[SkunkBoat]

those are fuel flow sensors

 

[Pfu]

those are fuel flow sensors

Thank you.

 

[SkunkBoat]

I'm assuming the fuel water separators are new this season?

Some air in the motor fuel filter is not unusual.

Were the motor filters off this spring and are you sure they got put back on right?

Assuming you are correcting in thinking it is fuel problem to both motors you need to bracket this problem.
First verify there is gas in both tanks. connect a known good fuel ball & hose to the elbow on the tank and verify you can pump gas out.
Verify its clean gas no water.
If you don't get good gas flow remove the hose barb which may be an antisiphon valve

if you can do that connect that fuel hose directly to a motor and test. bypass the selector valve, separator and flow sensor



There are a lot of things in the motors that can cause problems. Low pressure pump, high pressure pump, filter screens in the VST tank and between the VST and the pressure regulator

 

[Pfu]

To clarify my comment regarding the fuel valve. The way I understand it the main fuel tank is in the rear with the auxiliary in the front. In my boat both are 92 gal tanks. Would think the picture diagram would match Gulfstream diagram manual versus the opposite.

 

[SkunkBoat]

Look at the red or green tape on the hoses from the tanks. Look at the tape on the hoses at the tanks. do the colors match your vales?

 

[seasick]

Sounds like one motor has an air leak in the fuel plumbing.
If you can, take a look at the clear gas bowl and filter on the engine when the problem occurs. It should be mostly full. If it is empty or completely full, there is a leak.
If those filters were changed for the season, remove the bowls and reseat. They are know to not seat correctly.

Regarding the primer bulbs: If you have starvation due to a blocked vent, the bulbs will collapse. If they stay normal shape but soft to the squeeze, the vent is probably not your issue.
You may have water tin the tank. If so when you look at the clear gas bowl, look at the red ring if you have one. If it is floating near the middle to top, there is water in the fuel.

Also check the gas/water separators filters if they were changed this year. They may be leaky . Sometimes part or all of the old gasket sticks to the underside of the flange causing air leaks.

While you are at it, if you remove the filters, pour their contents into a clear glass jar and let the contents sit for 15 to 30 minutes. After sitting, look for different levels. If you have water, it will be at the bottom.
The good news (in a way) is that since both engines acted up, the issues is probably not the motors but rather a fuel issue.

keep notes on what motors connect to what tanks. Run one motor on one tank and the second on the other. If the problem occurs on only one motor, that indicates a problem in the tank or gas in the tank and not in the plumbing.
If switching the tanks moves the problem to the other motor, that tank is definitely the problem.

 

[Fishermanbb]

1. Connect a 6 gallon external tank with it’s own fuel ball/hose directly to your engines - one at a time and run them. If problem persists you have an issue with either filters or fuel pumps under the cowling. No problem running them then:
2. Change your water separators. Problem persists:
3. Change your fuel lines or look for damage. The problem here is that you are saying the issue is on both engines regardless of which tank they are beI got run on. It’s highly unlikely that both engines and both tanks have the same exact issue at the same exact time. However, rotted fuel lines, clogged in tank filters, racors, etc can all be the culprit. Any other work been done o the boat recently?

If you have gas in the tanks this sounds more like something is clogged as both engines/tanks are affected. If you are sure your hoses/primers are good I would start looking at the separators, VST filters, pumps, etc.
also, check to make sure your fuel valve is good.

 

[Pfu]

Sounds like one motor has an air leak in the fuel plumbing.
If you can, take a look at the clear gas bowl and filter on the engine when the problem occurs. It should be mostly full. If it is empty or completely full, there is a leak.
If those filters were changed for the season, remove the bowls and reseat. They are know to not seat correctly.

Regarding the primer bulbs: If you have starvation due to a blocked vent, the bulbs will collapse. If they stay normal shape but soft to the squeeze, the vent is probably not your issue.
You may have water tin the tank. If so when you look at the clear gas bowl, look at the red ring if you have one. If it is floating near the middle to top, there is water in the fuel.

Also check the gas/water separators filters if they were changed this year. They may be leaky . Sometimes part or all of the old gasket sticks to the underside of the flange causing air leaks.

While you are at it, if you remove the filters, pour their contents into a clear glass jar and let the contents sit for 15 to 30 minutes. After sitting, look for different levels. If you have water, it will be at the bottom.
The good news (in a way) is that since both engines acted up, the issues is probably not the motors but rather a fuel issue.

keep notes on what motors connect to what tanks. Run one motor on one tank and the second on the other. If the problem occurs on only one motor, that indicates a problem in the tank or gas in the tank and not in the plumbing.
If switching the tanks moves the problem to the other motor, that tank is definitely the problem.

Thanks for the ideas and comments. Will go through them one by one.

Note I purchased new fuel lines as too many cracks (old). Unfortunately couldn’t replace tonight as rain all day but tomorrow is another day.

 

[Pfu]

Finally got back to the boat and replace all fuel lines. Let me tell you not an easy job for a big man.

Pumped the fuel bulb on both and got fuel in the lines. Started starboard engine and ran like a top. Port engine starter kicks in but no luck in actually starting. Checked port battery and was low so opted to charge and go to lunch.

Came back and port battery fully charged but no go on starting. Tried on individual and both batteries with no change.

Back to the experts, what should I be looking for on the port engine to start. Good on fuel to the engine but can’t remember if there is something else electrical to the plugs. Getting close to actually being able to fish.

 

[seasick]

Check fuel delivery and spark first.
Squeeze the primer bulb to see if it gets firm.
I assume that the kill lanyard is inserted on that motor.

 

[Pfu]

Check fuel delivery and spark first.
Squeeze the primer bulb to see if it gets firm.
I assume that the kill lanyard is inserted on that motor.

Primer bulb is firm, fuel is at engine (no air remaining in filter). One lanyard runs both engines.

Not sure how to test spark. Will research.

 

[seasick]

You can buy a cheap spark checker at Harbor freight. Note that some motors don't fire all cylinders at low revs. I am not sure which cylinders are live at all times but I am pretty sure that cyl 6 is one of them.
If you feel up to it, one way to check for spark without a tester is to pull a spark plug wire, insert a screwdriver into the boot so that it makes contact and while holding the INSULATED handle position the metal shaft of the screwdriver close to the spark plug tip. When you crank over the engine, you should see and probably hear a spark jumping the gap. Having two sets of hands is probably necessary.

 

[Pfu]

Bought a tester so first thing tomorrow will check it out.

now to watch hopefully the final game of the Stanley Cup. Go Av’s!