1997 Evinrude 50hp VRO

[joelm]

A friend of mine is having some problems with his 50hp Evinrude VRO. The motor has the direct oil injection disconnected as he is mixing oil with gas. The problem is the motor will not idle properly, the low end idle adjustment screws are taken out and plugged off. He said that it didn't matter wether the plugs were in the holes or out, the motor ran the same. The motor doesn't want to idle at low rpms, but once your above idle the motor runs fine. Also, the motor will run and idle fine when in the driveway on the garden hose but once its in the water under pressure its stalling out. Hes replaced the plugs and decarbed the motor but still having the same problems. Any Ideas?? Thanks in advance!!!

 

[Daviet]

Re: 1997 Evinrude 50hp VRO

Can you post a model number, the one I looked at had adjustable needle valves for the slow speed settings.

 

[weekendfisher]

Re: 1997 Evinrude 50hp VRO

Has he just disconnected the VRO hose or has he changed over the pump as well?
My mechanic told me that of you just disconnect the hose eventually the VRO pump will dry out and the seals will crack then allowing air to get into the fuel so thins may be worth looking at.
When you remove the VRO you need to put the non VRO pump assembly in its place which is only a single diaphragm assembly.

 

[joelm]

Re: 1997 Evinrude 50hp VRO

He has had the VRO disconnected and the fuel pump changed over. I heard the motor run yesterday in the water, at 1/4 or less throttle the motor seemed to miss fire, once you got above that it ran great

 

[boobie]

Re: 1997 Evinrude 50hp VRO

I've seen a lot of vro pumps run a long time with the oil side disconnected. The fuel vro side makes a good fuel pump.