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1986 90HP VRO Hard to start when warm

C

cordun

New member
When I try to start my 1986 90HP VRO after it has been running for awhile it is hard to get going. Cold starting is fine, I pump the ball a few times (which does not get hard) choke it pull the control to high idle and it fires right up. It warms up fine. Sometimes when I go to put it in gear, it stalls but it still starts right up and then when put in gear runs fine. It idles good a low rpm when I get to where I am going. Then after shutting it down and fishing for awhile I try to start it by turning the key it turns over and over but will not fire. When it finally does fire, it will not rev up by bringing the high idle lever up (the lever is right up and it barely turns 1000-1500 rpm. I have tried different things when starting it warm like priming the line again, choking it and just turning the key but it still does the same thing, no firing right away ( I have to crank it over and over and over to get it to fire) then when it does fire no RPM out of it? Any thoughts on what is making it do this? BTW the plugs are new and are the correct type, and they have a nice color to them.
 
On a cold start the manual fuel pump ( primer bulb ) must be operated till it goes hard.-If it does not go hard there is something wrong.--------Excessive cranking will damage the starter motor and slow cranking means " no spark " and a no start condition.-----Are you running with VRO in use ???----Have you done a compression test ?----Does spark jump a gap of 7/16" on all four with the sparkplugs left in ?
 
I just bought this boat, but ever since I had it the primer bulb does not get hard. I tried a different primer bulb but it still does not get hard. I tested the bulb and it does pump the fuel but it does not stay hard when connected to the motor. The motor starts fine when cold and runs fine otherwise it is just the warm starting that it has trouble with. The VRO is in use and there are no alarms going off. I have not done a compression test and I'm sure the coils are fine because it does start right up cold. The starter does crank the motor quick. I am wondering if this could be a flooding problem?
 
Simply put , when operating the manual fuel pump ( primer bulb ) it must go hard.-If it does not then there is something wrong !!--Check / replace o-rings at fuel connecters. ------It does not need to be hard when the motor has started and is running.-----------Remove cover in front of carburetors and see if there are leaks when you operate the bulb.--------Turn key to " on " and push in the key, do you hear the click from the electric primer and where is the lever positioned on the electric primer ??
 
The o-rings are good, no leaks at the carb, I have install new fuel lines from the tank to the motor and I hear the clicking from the choke when I push the key in.
 
The starting point of any trouble shooting on an outboard is to do a compression test when the motor is cold and hot.
If the bulb does not go hard then you have a problem. You have a leak in the fuel system which could include the carbies or the bulb is no good. Maybe a restriction in the tank.
 
make sure the oring in the gas line connector is good...the connector at the engine....also make sure that the little lever that snaps down in a little groove does so when you connect the line to the motor....that is a close fit on those motors and the seat where the connector bottoms must be clean or it will not snap in place...the symtoms are somewhat the same....no gas leak when pumping the bulb but i think you are sucking air back in when you release the bulb ....the motor will normally run well when its running because you have compression helping you suck gas but the carbs are not at the right level when you go to start it.....another symtom is when running with a really loaded boat is just all of a sudden slowing down and coming off the plane and eventually stopping....i agree with all of the above entries..you have a problem with the bulb not getting hard and that must be fixed first in my opinion...i ran a 90 for 18 years......
 
another little tip on that engine.....it needs a 3/8 inch fuel line from the tank to the motor....1/4 will work when its new but eventually when it closes a bit you have a problem...this is probably not your problem now i dont think though...
 
a good tool to put in the boat is an inductive timing light....on the chance that you do have a fire problem it would be easy to see with your failure......thats always the first decision i want to make when an engine dont start..is it fire or fuel?its a possibility that the fuel system has always been like that and now you have a 2nd problem.....i have had stators give me the same symtoms you have but they usually go out the next trip or two...then you are dead in the water....
 
Hello. Found this thread from many years ago. I have a 90 horse vro with same warm starting issue. Did you ever find the solution? Thanks!
 
Malbert----Start a new thread.----Post your actual compression values.-----Post the cold starting procedure you use on this motor.
 
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