1994 115 Johnson V4 crossflow

Fishjustin87

Petty Officer 2nd Class
Joined
Aug 7, 2018
Messages
113
I picked up a starter boat as a project to play with. It has a 94 115 Johnson on it. I have hood spark and all 4 cylinders are at about 125 to 130 with a wet test. I rebuilt the carbs and have had a problem with the VRO No oil sensor. Did the Vro oil test and its seems fine. I am losing vaccum in the tank. I am going to replace the oil pickup gasket to see if that fixes the no oil alarm. It fires and idles with a slight miss if I lift the throttle just a tiny bit but dies if I drop it all the way. Notices when I rechecked the compression that cylinder 2 and 4 had a little bit of water oil mix on the plug. Compression on 2 was 128 and 4 is 125. Could this just be a small leak in the head gasket? On a side not I get alot of oil in the water tank it's in after run ing for a little bit. Obvious thing to do is pull the head but is it more possibly the crank seal? I. Confused as to why compression appears to be good. It is an older motor that I would like to get one summer out of so I can upgrade to a bigger boat next year for the family and not be "That Guy" at the boat launch. Also if I manually fed the tube for the VRO test it did not sound the alarm. Let run 45 Minutes. New oil cap, pump the ball and oil comes out the line but can not blow back through to the tank from the main oil hook up point.
 

Fishjustin87

Petty Officer 2nd Class
Joined
Aug 7, 2018
Messages
113
I should specify that I believe that I have no air leaks from the primer bulb down to the VRO. I still want to replace the gasket at the tank pickup because the only other thing that I can think of is that I must have an air leak from either at the tank pickup or the pickup itself is not working for some reason. The main thing I am trying to figure out though is why I have water on two plugs. Both olugs on the same cylinder head makes me think head gasket but still having good compression confuses me.
 

Fishjustin87

Petty Officer 2nd Class
Joined
Aug 7, 2018
Messages
113
If I understand the VRO system correctly than the oil line must hold some kind of vaccum for the number 2 cylinder to pull oil through the system. Unless I am wrong as to how the vro works
 

racerone

Supreme Mariner
Joined
Dec 28, 2013
Messages
38,552
Your understanding is totally wrong -------Fuel pumps on outboard motors work from a positive pressure pulse and a slight vacuum pulse.----The VRO is a combination oil / fuel pump.-----I do not believe that the #2 cylinder comes into the picture for the VRO pump.
 
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