Johnson GT 150 dies at 75% throttle.

[silverside]

I have a 87 Johnson GT 150 on the tail end of a 83 Hydrasport x270 17' that has started dieing at about 75% to 80% throttle. I know its fuel related, no question there, lifting the hatch and the fuel line has no fuel at all, pump still running, I can re-prime the line and start up and take off again but if I try to hit that top end it dies and I'm back with the re-priming. I have the VRO removed and I mix my fuel no, I have a universal in-line pump.

My guess is the pump is starting to go and isn't meeting the fuel demand for the outboard. Is there anything else that I should look into, that hopefully isn't too much to deal with.

 

[kenmyfam]

Re: Johnson GT 150 dies at 75% throttle.

Check the pump output. If it starts well and then tapers off either the pump is on the way out or you have some air intrusion in the lines.
Welcome to iboats.

 

[emdsapmgr]

Re: Johnson GT 150 dies at 75% throttle.

Have a friend constantly prime the fuel hose bulb. See if it will run high rpm's while this is being done. If the engine runs fine at WOT while constantly priming the hose bulb-likely you have a fuel delivery problem. It sounds like you have a single inline fuel pump on your engine. The early versions of this V6 engine that used the simple bladder pumps came with two pumps, installed at the factory. Not sure if your single pump is rated to handle the fuel demands of this powerhead. These older dual pumps will work fine in your application. You may want to check out the factory parts lists for a 79-83 V6 block at this website: epc.brp.com. Note that the two pumps are different part numbers. Another option is to install a newer factory pump which is a VRO type, but does not have the oil pump. (you'll have to premix) It's about $100 cheaper than the original VRO type pump which came on the engine.

 

[silverside]

Re: Johnson GT 150 dies at 75% throttle.

I'll see what I can do with it today. I'm hoping its just a simple got pick up another pump. To my knowledge since the VRO was removed this is the second in-line its had. One of which I put on it 4 years ago, so I'm not gona complain if its a $50 pump. At-least I'm not rebuilding the lower unit again.

 

[silverside]

Re: Johnson GT 150 dies at 75% throttle.

Fuel pump was failing, completely gone now. Suppose whenever I am able to get enough money together instead of getting one I'll get 2 so ill have an extra on onboard.