Help please! 1988 Johnson outboard lack of power and stalls.

[Johni1cars]

Thanks in advance to anyone that can help me out. Its a 1988 johnson outboard with 200hrs on it. I've own it for 7 years. Motor has been amazing. Best toy I have ever owned. Ran perfectly until this year. I decided to do the water pump impeller this spring bc It's never been done. Motor not the same since. Put it in the lake. Starts up fine, after driving for few minutes stalls. Pump primer was soft pumped up and starts up again. Same thing. Thought I had a bad tank. Switched tanks. Next time I went out same thing .. stalling after a few minutes out on the water...next time I went out changed primer bulb and fuel line. Same stalling issues. Fuel filter replaced with a clear wix fuel filter. Noticed that the filter was emptying out. I felt that the carbs were starving for fuel. Everyone I spoke to said the vro pumps on these motors are bad news. To be honest I love this vro system...works perfectly. So I did the vro delete and put on a cheap Amazon pump on the side of the block. Premixed my oil and gas...It might be a touch rich...like 50ml...it's a 23 liter tank. Since then the motor runs better when choked...fuel inrichment on. It won't hold an idle. Rebuilt carbs. Compression is 150 top and 145 bottom. Checked spark. Seems good...it's loud and when I disconnect a cylinder engine stalls. Checked resistance of coils... 245 each. I tried playing with mechanical timing adjustment. No luck. On my last try out on the lake I noticed the motor ran better. Still won't hold an idle with throttle closed in neutral and lack of power doesn't seem to stall any more while driving....power pack? Bad fuel pump? Thermostat? Or did I screw something up when changing the impeller and taking lower unit off. Please help.

 

[saltchuckmatt]

Thanks in advance to anyone that can help me out. Its a 1988 johnson outboard with 200hrs on it. I've own it for 7 years. Motor has been amazing. Best toy I have ever owned. Ran perfectly until this year. I decided to do the water pump impeller this spring bc It's never been done. Motor not the same since. Put it in the lake. Starts up fine, after driving for few minutes stalls. Pump primer was soft pumped up and starts up again. Same thing. Thought I had a bad tank. Switched tanks. Next time I went out same thing .. stalling after a few minutes out on the water...next time I went out changed primer bulb and fuel line. Same stalling issues. Fuel filter replaced with a clear wix fuel filter. Noticed that the filter was emptying out. I felt that the carbs were starving for fuel. Everyone I spoke to said the vro pumps on these motors are bad news. To be honest I love this vro system...works perfectly. So I did the vro delete and put on a cheap Amazon pump on the side of the block. Premixed my oil and gas...It might be a touch rich...like 50ml...it's a 23 liter tank. Since then the motor runs better when choked...fuel inrichment on. It won't hold an idle. Rebuilt carbs. Compression is 150 top and 145 bottom. Checked spark. Seems good...it's loud and when I disconnect a cylinder engine stalls. Checked resistance of coils... 245 each. I tried playing with mechanical timing adjustment. No luck. On my last try out on the lake I noticed the motor ran better. Still won't hold an idle with throttle closed in neutral and lack of power doesn't seem to stall any more while driving....power pack? Bad fuel pump? Thermostat? Or did I screw something up when changing the impeller and taking lower unit off. Please help.

Amazon fuel pump is crap, you didn't tell anyone the HP or better yet the model number.
Could be many things so maybe slow down, and systematically rule out things.

 

[jimmbo]

VRO Pumps are not Bad News, they are actually quite Reliable.
You rebuilt the Carbs? What parts did you change, and what adjustments did you do inside the Carbs?
Also, when you put the Carbs back on the Engine, did you make sure both carbs were fully closed at idle, and that you checked the Sync between the Ignition Timing and the Carbs?

 

[racerone]

Sounds like a 2 cylinder 50 HP.

 

[Johni1cars]

Correct its a 2cyl 50hp. J50tTLCCS
In the carbs... purchased 2 carb kits from the local marina sierra brand. Owner recomended it. Replaced needle, seat, and gaskets. I soaked them in berryman carb dip for 2 days. Both the top jet and the one in the float bowl were clear, and so were the 2 tiny holes near the butterly. The carb has no adjustments origionally the float hung down over 3/4 and was not parallel to the body...that was the only adjustment I corrected as per instructions in the rebuild kits.

 

[Johni1cars]

Yes both carbs open and close at the same time. I didn't need to make any adjustments to the sync. The mechanical timing linkage moves with the throttle linkage. All linkage are tight. I totally agree these vro systems are amazing. I had no issues with it. But I thought the fuel side got lazy and that's why I deleted it.

 

[racerone]

Checked the flywheel key ?-----Nozzle gaskets in place?-----Timing on these motors is " fixed " for the life of the motor.----Careful if you decide it needs adjusting !!!

 

[tphoyt]

Maybe I miss read your float adjustment procedure but did you adjust the float with with carb right side up or upside down?

 

[Johni1cars]

I haven't removed the flywheel. But i cant see how the key would get sheeared of the fly wheel. It is tight and i never removed it. I did play with the mechanical timing ajdudmtent...but I put it back where I found it. Tphoyt...when I check for the drop of the float the carb is right side up. Needle open. When I check for need closed the float is parallel with the body of the carb...upside down.

 

[Johni1cars]

Racerone just saw that...Whats the nozzle gasket?

 

[tphoyt]

Yep I miss understood what you said.
Flywheel keys can and do sheer.
The flywheel only needs to rotate a tiny bit to throw off the timing. There is only one way to know for sure and that is to check. It’s a free test and you can rule it off your troubleshooting list.

 

[Johni1cars]

Thanks, I will definitely check when I get the boat out of the water in a few weeks.
Is it possible to put a screwdriver in cylinder 1 and bring the piston to tdc and see where the timing mark lines up.

 

[jimmbo]

The Piston will be at TDC for several Degrees of Crankshaft Rotation. Many engines use a specific Distance from TDC to determine/calibrate the Timing Pointer.
It would be easier just examine the Key once the Flywheel Nut is removed, for any shear

 

[flyingscott]

You either did not put the nozzle gasket on. That goes inside the float bowl. Or you put the top gasket on backwards. The idle circuit is in that top cover. To set the float hold the carb upside down and set the float to level.

 

[racerone]

Screwdriver in the plug hole is one way to check the key.----You can not find a sheared key by just removing the nut.-----You can not find a sheared key with a timing light either !

 

[Johni1cars]

Thanks racerone. I will check this when I get it out of the water. I definitely put the nozzle gasket on that sit on the center of the float bowl. And the float bowl gasket only goes on one way.

 

[flyingscott]

I am talking about the gasket on top of the carb. Not the float bowl gasket

 

[Johni1cars]

There is no gasket on top of the carb. only gaskets are the circular on in the center of the float bowl and the one that seals the outside of the float bowl.

 

[flyingscott]

Doesn't that carb have a plastic top? And are the throttle rollers in good shape?

 

[Johni1cars]

No Sir.