HELP! , Port engine not staying cranked.

[Kirby Kelley]

Anyone with any input please reply. I started having trouble last weekend. Been out using the boat all day, pulling kids on tube and just generally having fun. Pulled up on a beach for several hours and when I got ready to leave the port engine would turn over but not start. Got the boat back to dock and on the trailer and took it home. Got home and it cranked right up. I went out and cranked it every day. I hooked it up to take to the lake for July 4th outing and I cranked it before I left and it cranked fine. I got it to the lake and put it in the water and the port engine would not crank. I took the boat back home and since then I have been able to get the port engine to crank for about 30 seconds and then it won't crank again for about a day or so. Do I have a carb problem or what? Any help would be appreciated.

 

[bronze_10]

Sounds heat related.. Maybe a sensor or another electronic component get hot and faults.

 

[Kirby Kelley]

I don't think that it is heat related because it doesn't stay cranked long enough to create much heat. Maybe electronic but I don't have a good understanding of the electronics on this boat.

 

[4x15mph]

Can you describe what you mean by cranked? Engine running?

If the starter doesn’t engage and there is no noise when you turn the ignition and this is intermittent, I would check your safety switch on the plug cleanout hatch. Have someone press on the switch or tape a quarter on the hatch temporarily to see if that helps.

 

[the MfM]

The safety switches on the plug cleanout hatch and the neutral safety switch can keep the engine from turning over.

The lanyard if removed/faulty will allow the engine to turnover but not fire.

Also check the ground at cable at the battery. There is one for each engine.

If not any of the above it’s likely the starter relay or starter itself. When you turn the key and it’s not turning over listen for a slight click coming from the starter relay behind the engine. If you here the click then I’d suspect a bad starter.

If you don’t here the click you can double check that it’s not a safety switch by swapping the port and starboard wiring harnesses behind the helm. Obviously the key switch will then start the opposite engine. Still no click, replace the relay.

 

[boudin]

These are the 65U NPV motors, right? I'm reading your first post, and it sounds like it's not cranking once the engine gets warm? Can you do a compression check?

-Greg

 

[Kirby Kelley]

These are the 65U NPV motors, right? I'm reading your first post, and it sounds like it's not cranking once the engine gets warm? Can you do a compression check?

-Greg

I don't think it's a heat problem because it only cranks for about 30 seconds then goes dead. It is seeming more like some kind of carb problem or maybe a stuck choke. I don't have anything to do a compression check with, I would have to take it somewhere. I don't have much time to do anything to it during the week. Thanks for the input though.

 

[the MfM]

I think we need a clear definition of you mean by cranks/cranking/cranked.

If the starter is not turning the engine over every time you turn the key it has nothing to do with the choke, carbs or compression.

 

[boudin]

I've seen plenty of 65Us with a lean seizure when warm, but will still turn over when cold.

As you say, could also be the starter relay or starter, or as simple as a corroded ground, corroded positive connection to the starter or even a weak battery.

-Greg

 

[the MfM]

I've seen plenty of 65Us with a lean seizure when warm, but will still turn over when cold.

As you say, could also be the starter relay or starter, or as simple as a corroded ground, corroded positive connection to the starter or even a weak battery.

-Greg

True regarding a lean seizure, But I think he is saying that the starter will turn the engine over for 30 seconds an NOT start. And then the engine/starter will not spin. The next day he can get it to turn over again? To me that seems more like a relay/starter or maybe corroded connections at battery or starter.

I wouldn’t think cranking the engine for 30 seconds would lock it up but I suppose it could... More so if the oil injection system has been removed and he is running premix.

 

[boudin]

To start, check voltage on the positive to the starter during cranking.

 

[Kirby Kelley]

The starter turns the boat over and it cranks and runs for about 30 seconds and then when I give it a little throttle it goes dead. The battery is new and I keep it charged when the boat is not in use. I meticulously keep the battery terminals clean.

 

[4x15mph]

1) safety hatch switch could be out of alignment and adding throttle could be shaking the hatch enough to engage that "kill switch". Tape a quarter over that engine side switch
2) Carbs.... one way to verify would be to swap the carb racks since you said the other engine is working well.
3) other possibility would be the ECU/wiring but I would start with 1 and 2 above

If you don't know the history of when the carbs were rebuilt last, you should be planning to do that now as a preventative step anyway. It is not something you want to prolong honestly and it is easy if you don't replace the springs. More on the process if you decide to do this yourself. If you bring this to someone it will be ~$700 with parts and labor or more but still a necessary maintenance item for our carborated boats

 

[the MfM]

I’d say @boudin was right and it’s time to check compression.


Could also try fresh spark plugs as they are probably fouled at this point.

 

[boudin]

Carbs should be proactively rebuilt every 2-3 years on all the Yamaha 2-strokers. Will save you lots of headache. Not saying this is the problem here, but dirty carbs can lead to lean conditions and major problems, especially if the boat is on premix.

-Greg

 

[the MfM]

Also check the fuel filter.

 

[boudin]

Is there a fuel filter on the boats? On the waverunner 65Us there is not, just an intake screen and flapper, which can get clogged. It's at the end of the fuel pickup inside the tank. Good idea to check that.

-Greg

 

[the MfM]

Yes two fuel filters and two pickups.

He could swap the fuel lines after the filter to rule out a fuel supply problem.


(But only try to run the port engine on the starboard fuel line... don’t run the good engine with the lines swapped)

 

[boudin]

Yes two fuel filters and two pickups.

Ahh yes, of course. I see it in the diagram now.

 

[Kirby Kelley]

Also check the fuel filter.

I put b

Yes two fuel filters and two pickups.

He could swap the fuel lines after the filter to rule out a fuel supply problem.


(But only try to run the port engine on the starboard fuel line... don’t run the good engine with the lines swapped)

I replaced both fuel filters in early spring. I replace them in the spring every season . I have had the boat for a little over 3 years and the problem is looking like a carb problem. I am going to look at rebuilding them. do you know of any good rebuild kits. I think that I am going to try to do them myself because boat repair labor is so expensive. If I can get the port engine done successfully then I will also do the starboard engine