Wont run in the water HELP

[BOATINGTN]

Hello guys new to the forum. Picked up a 1990 Sunbird runabout has a Johnson V4 90hp motor.

Installed fresh plugs cleaned the carbs check compression and installed new plug wires.

Checked shift and throttle linkage.

Has great fuel pressure.

I have used water ears and she will run fantastic nice and responsive fires up idles fine.

I took it last weekend to the lake dropped it in. It took a while to fire up got to run it for about 15 mins It ran pretty smooth. Went back to dock to pick up a passenger and that when the trouble started.


Basically when I use the ears it works great. When I put it in the water and submerge the bottom end it will only idle. When I go to rev it in neutral it dies.

Could there be something in the lower unit or exhaust stalling it out. Something with the back pressure?

I would appreciate any help.

 

[BOATINGTN]

Re: Wont run in the water HELP

Is it the way I asked the questions?

 

[Willyclay]

Re: Wont run in the water HELP

Welcome to the forum! The experts here, which I am not, can help you with any issue involving your boat, motor and trailer. Hopefully, one of the experts will post in your thread to help you get started. Meanwhile, it might be helpful if you post your motor's model number and pictures always help. In this case a picture of your boat's transom showing how the motor is mounted may answer your question about "back pressure". Most outboard motors will act very badly when the exhaust relief holes are under water. Your observation seems to verify that. The fix could be as simple as re-distributing some weight forward in your boat or possibly raising the motor on the transom. Good luck!

 

[Mr. Coffey]

Re: Wont run in the water HELP

I'm no expert, either, but I have experienced motors that would idle OK, but bog-down and/or stall when throttled-up. Turned out to be water in the fuel. Low fuel flow during idle allowed fuel to leave the water behind. Higher fuel flows caused water to be drawn into the carbs. Maybe check your carb bowls again for water and, if you haven't already, install a Racor-style fuel filter with a clear bowl so that you can see if there is water in the system. Maybe the position of the boat afloat causes water in the fuel tank to drain toward the pickup tube, while it might not on the trailer. Just something to think about.

 

[jonesg]

Re: Wont run in the water HELP

Hello guys new to the forum. Picked up a 1990 Sunbird runabout has a Johnson V4 90hp motor.

Installed fresh plugs cleaned the carbs check compression and installed new plug wires.

Checked shift and throttle linkage.

Has great fuel pressure.

I have used water ears and she will run fantastic nice and responsive fires up idles fine.

I took it last weekend to the lake dropped it in. It took a while to fire up got to run it for about 15 mins It ran pretty smooth. Went back to dock to pick up a passenger and that when the trouble started.


Basically when I use the ears it works great. When I put it in the water and submerge the bottom end it will only idle. When I go to rev it in neutral it dies.

Could there be something in the lower unit or exhaust stalling it out. Something with the back pressure?

I would appreciate any help.

THeres no load when running on the hose.
You "cleaned" the carbs, they need to be rebuilt with a kit.
See the top secret sticky FAQ files for directions.

If you did that and its still a problem, test the ignition spark on all 4 with an adjustable gap tester. Again see top secret file.
http://forums.iboats.com/showthread.php?t=299680

 

[BOATINGTN]

Re: Wont run in the water HELP

Thanks for help and the welcome to the forum. I will get some pics tonight and post them. To see if the motor is to low in the water.

 

[BOATINGTN]

Re: Wont run in the water HELP

Thanks for the replys. It ended up being the idle was to low. It was running 1000 dry dock so I moved it up to 1400 and she did fine. Now fine tuning.

Thanks again.