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Help with Johnson 89 50vro

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Dieselmech0331

New member
Bought a new to me boat that has an 89 50vro. It was running like a top and the surged and slowly stalled out. After this happens it takes a while to get started back up and then you can get on plane but within 30 seconds will bog down and stall out. Seems like a fuel issue but was curious if anyone has had the same issue. Thanks for help in advance.
 
If the fuel primer bulb has a tendency to collapse, flaten out somewhat... that indicates a fuel restriction.

Have someone constantly pump the fuel primer bulb, acting as a manual fuel pump, to see if that cures the problem. If it does... and no air/fuel leaks are evident, suspect that VRO.

Let us know what you find.
 
joereeves said:
If the fuel primer bulb has a tendency to collapse, flaten out somewhat... that indicates a fuel restriction.

Have someone constantly pump the fuel primer bulb, acting as a manual fuel pump, to see if that cures the problem. If it does... and no air/fuel leaks are evident, suspect that VRO.

Let us know what you find.
Click to expand...

I have bypassed the vro. Capped off the wires and disconnected the feul line and plugged the oil intake. The fuel pump is separate isnt it.
 
The VRO is a dual pump.... it pumps fuel and oil, mixes it internally, then distributes it to the carburetor(s).

You state that you've plugged the oil line and disconnected the fuel line. hat is your plan for having the fuel delivered to the carburetor(s)?

Capped off the VRO wires? Simply unplugging it eliminates any possibility of a VRO warning reaching the warning horn.
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(VRO Pump Conversion To Straight Fuel Pump)
(J. Reeves)

You can convert the VRO pump into a straight fuel pump, eliminating the oil tank and VRO pump warning system, but retain the overheat warning setup (and fuel restriction warning if so equipped) by doing the following:

1 - Cut and plug the oil line at the engine so that the oil side of the VRO pump will not draw air into its system. Trace the wires from the back of the VRO to its rubber plug (electrical plug) and disconnect it.

2 - Trace the two wires from the oil tank to the engine, disconnect those two wires, then remove them and the oil tank.

3 - Mix the 50/1 oil in the proper amount with whatever quantity fuel you have. Disconnect the fuel line at the engine. Pump the fuel primer bulb until fuel exits that hose with the tint of whatever oil you used. Reconnect the fuel hose.

That's it. If you want to test the heat warning system to ease your mind, have the key in the on position, then ground out the tan heat sensor wire that you'll find protruding from the cylinder head. The warning horn should sound off.
********************
 
joereeves said:
The VRO is a dual pump.... it pumps fuel and oil, mixes it internally, then distributes it to the carburetor(s).

You state that you've plugged the oil line and disconnected the fuel line. hat is your plan for having the fuel delivered to the carburetor(s)?

Capped off the VRO wires? Simply unplugging it eliminates any possibility of a VRO warning reaching the warning horn.
********************
(VRO Pump Conversion To Straight Fuel Pump)
(J. Reeves)

You can convert the VRO pump into a straight fuel pump, eliminating the oil tank and VRO pump warning system, but retain the overheat warning setup (and fuel restriction warning if so equipped) by doing the following:

1 - Cut and plug the oil line at the engine so that the oil side of the VRO pump will not draw air into its system. Trace the wires from the back of the VRO to its rubber plug (electrical plug) and disconnect it.

2 - Trace the two wires from the oil tank to the engine, disconnect those two wires, then remove them and the oil tank.

3 - Mix the 50/1 oil in the proper amount with whatever quantity fuel you have. Disconnect the fuel line at the engine. Pump the fuel primer bulb until fuel exits that hose with the tint of whatever oil you used. Reconnect the fuel hose.

That's it. If you want to test the heat warning system to ease your mind, have the key in the on position, then ground out the tan heat sensor wire that you'll find protruding from the cylinder head. The warning horn should sound off.
********************
Click to expand...

I must have typed wrong. I did everything on the list you just stated. I got the instructions from here. Sorry for the misunderstanding. If the pump is the issue is it possible to replace the vro pump with a normal fuel pump instead of spending 400 dollars
 
Dieselmech0331 said:
I must have typed wrong. I did everything on the list you just stated. I got the instructions from here. Sorry for the misunderstanding. If the pump is the issue is it possible to replace the vro pump with a normal fuel pump instead of spending 400 dollars
Click to expand...

Okay... Just wanted to be sure you were "tinkering" with that setup as that (errors) could get expensive. Glad to hear that you changed over properly.

Yes, many members have already done just that. However I do not have knowledge of the exact small regular fuel pump part number. I'm sure that another member will be jumping in here with that info shortly.
 
Find the part # for the fuel pump off a 48 HP model.-----Many years !-------Uses a pump screwed directly over a pulse port on the port side of the top cylinder.----A simple cheap pump.-----Really cheap if you are comfortable with chinese ones sold all over the internet.
 
Well new development. I replaced fuel line and bulb and went out to see. Ran great for 30 minutes. Once it warmed up it began to stall itself out while on plane and was hard to get started and would allow you to get on plane and repeat. I'm stumped. Seems like if it was something fuel related it would be more consistent
 
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