1988 Johnson 40 HP VRO

[Adamh21]

Hello All,

I have a 1988 Johnson 40 HP VRO; the VRO system has been disabled. I ran the boat this past weekend. Started up great but I accidently left the ventilation on the tank closed. Ran for about 30 minutes then stalled. Once I realized the issue I opened the valve now the engine will not start and stay idle. The boat will turn over and idle for about 30 second then stall out right again. Any help would be appreciated. Thanks.

Edit: Lower unit was replaced last year and carbs were cleaned recently. Also I replaced the spark plugs this past weekend.

 

[tashasdaddy]

Re: 1988 Johnson 40 HP VRO

is the hose connected with the arrow on the bulb pointing toward the motor? if you pump bulb will it continue to run?

 

[Adamh21]

Re: 1988 Johnson 40 HP VRO

is the hose connected with the arrow on the bulb pointing toward the motor? if you pump bulb will it continue to run?

Yes the arrow is pointing the correct way and the bulb does continue to run when pumped. I just find it amazing that I am having so many issues with it now when it ran great. I forgot to open the valve once now the thing won't start.

 

[tashasdaddy]

Re: 1988 Johnson 40 HP VRO

it could have cause some crud to be sucked into the carb jets.

 

[The-Machinist]

Re: 1988 Johnson 40 HP VRO

If you can pump the bulb, and the engine will stay running I wuold look at the fuel pump. I have a disabled vro 50 that sucked a plastic tank nearly flat, I dont know if it was a direct result, but the diaphram in my fuel pump gave up during that excersise in sillyness.
Just somthing to check.

 

[Adamh21]

Re: 1988 Johnson 40 HP VRO

it could have cause some crud to be sucked into the carb jets.

Thanks for all the replies. What would be the quickest way to clean it? Do I need to take apart the carb to clean the jets?

I actually tried pumping the ball trick today and it got the motor to start. Funny thing is the motor actually started idles for about 15 - 20 minutes. So I decided to take it out. Now the engine won't get up to full throttle. Eventually stalled out after 40 minutes; tried getting up to full throttle a few times which made it stall out.

 

[Adamh21]

Re: 1988 Johnson 40 HP VRO

Any other ideas or tips?

Thanks,

 

[tashasdaddy]

Re: 1988 Johnson 40 HP VRO

http://forums.iboats.com/showthread.php?t=244013

 

[Adamh21]

Re: 1988 Johnson 40 HP VRO

Thanks for all the helpful replies. I still think I need to clean the carbs but what has been happening seems a little weird.

I replaced the fuel line from the engine to the tank this week. Engine starts up great on land. Once I place in the water it starts right up but once I get it going it stalls right out then won't restart until I get it back home. Then once I am home it starts right up again. So it seems once the propellor has any resistance the engine stalls.

Still a carb issue or something else?

I searched around the forum and saw other people had this issue but it was related to a bad cylinder. When I pull off the plug in one cylinder it loses power and same deal with the other cylinder. So I am unsure of where to go from here?!

 

[tashasdaddy]

Re: 1988 Johnson 40 HP VRO

sounds like a carb issue, also an idle rpm issue. it should idle at 650-750 rpms, in the water, in gear. it will idle higher in neutral, and even higher in the driveway, do to no backpressure on the exhaust. will probably idle 900-1000 in driveway.

 

[Adamh21]

Re: 1988 Johnson 40 HP VRO

sounds like a carb issue, also an idle rpm issue. it should idle at 650-750 rpms, in the water, in gear. it will idle higher in neutral, and even higher in the driveway, do to no backpressure on the exhaust. will probably idle 900-1000 in driveway.

Thanks for all the help tash. I guess I will be cleaning the carbs once the rain lets up.

 

[JohnnyRuuDe]

Re: 1988 Johnson 40 HP VRO

One other thing to consider, forgetting to open fuel tank breather could have caused an air leak somewhere in your fuel line. This may cause air to be drawn into the fuel system resulting in "foamy fuel". This messes with the air to fuel ratio causing problems...might be worth checking out. -Good Luck