Vro pump Jonhson 1996 40hp modification

[leotzian]

Hi
I have a Jonhson 40hp 1996 model
I want to use the vro pumb only with mixed gas with oil
I had read I have to disconnect the cables for the alarm leds, disconnect and close the oil supply, and mix the gas with 1% oil
1) Is that correct?
2) Will the vro pump work ok with no oil sypply, or it will blow out? because the service men in Greece say that the vro pump will fail because the pump was lubricated with the oil supply, and they must put a gas only pump to do the job

Is this correct or they lie?
Do you suggest to do that or leave vro as it is?

Thanks in advance

 

[seahorse5]

Re: Vro pump Jonhson 1996 40hp modification

Hi
I have a Jonhson 40hp 1996 model

... and mix the gas with 1% oil

Your engine would require a 2% oil premix, not 1%

 

[d.boat]

Re: Vro pump Jonhson 1996 40hp modification

I used a "gas only" vro pump for about 8 years, no problem. I have no idea if the oil side will be damaged w/ no oil, but it will not affect the fuel side. Just make an airtight plug with a hose clamp on the oil inlet hose, disconnect the tank and fuel pump wires and your'e good to go.

If both the oil and gas parts of your pump are working, why change it? Although I used premix on that old engine of mine, on my newer engine, the VRO/OMS system is working. I've read up on the maintenance and operation and am convinced that it is more reliable at mixing the oil and gasoline than I was.

But, like he said, it's 2%, not 1% if you are going to premix.

 

[leotzian]

Re: Vro pump Jonhson 1996 40hp modification

Thank you all
I have this post http://forums.iboats.com/showthread.php?t=426018

Please read it, and give me an idea
I am searching for the pump if the pump is the cause of my problem

Tell me is you have any ideas what to look for
I have no alarms like no oil hot etc, perhaps the carbs I have not used it for 2 years but mice got in the motor, they eat some of the cables and the hoses ( fuel lines, I replaced the cables , and changed the gas lines ).
I am electronic technitian, I did all right

I am sure that my problem is fuel problem

Any ideas please...

 

[wilde1j]

Re: Vro pump Jonhson 1996 40hp modification

I have no idea what your problem is, other than maybe something to do with the VRO/OMS pump. Please explain so someone can help!

OK looked at the other thread ... a clumsy way to post.

Some things to try to determine if it's a fuel delivery problem, which can have a number of causes, such as:
. air leak on pump suction side (bad clamp, cracked hose, cracked tank pickup tube, etc., etc.)
. malfunctioning anti-siphon valve
. plugged tank vent
. trash blocking tank pickup screen
. plugged fuel filter
. collapsed fuel line
. water or trash in internal and/or external filter
. try squeezing primer bulb or activating the choke/primer when RPM sag
. try an alternate fuel source (i.e. portable tank)

FUEL PUMP OUTPUT TEST

1) Pull the safety lanyard so the motor can't start
2) Disconnect the pump outlet hose
3) Crank engine ... should get long strong spurts, any less is reason to replace/rebuild

OR

Put a pressure gauge teed into pump outlet line ... should read ~ 3 to 6 psig on a good pump with engine running.

BTW, the fuel side of the OMS pump is rebuildable.

 

[leotzian]

Re: Vro pump Jonhson 1996 40hp modification

Than you all, I will do all these and come back

 

[leotzian]

Re: Vro pump Jonhson 1996 40hp modification

Hi all again
I am coming to tell you what I have done after all your advices

I changed fuel line from the tank, changed spark plugs, changed all fuel lines in the motor, cleaned the carbs ( there was ok I found no problem) disabled VRO disconnected oil line, closed the line, disconected the cables from the vro and from the tank, and I mixed the gas with oil 50:1
Checked everything, no leaks of fuel.

I checked the motor out of the water in a barrel it was all ok.
then I put the boat in the sea.

The problem still exist but a little different
In idle the motor sounds ok, my boat is 4 meters with 2 persons in when I was putting the throttle at full position the boat was almost at once inreasing speed until 4500 rpm ( 25-28 miles speed )
Now it seams that it has not the power that used to had, it makes more time to increase speed, and the sound it is not continious the same, it seems that the rpm are not stable, ( It is not very easy to discribe and my English are not so good ), when I press the choke the motor getting better and the rpm are rising, All this time I press the tanks primer bulb and it is firm meaning the carbs are full of fuel.
The engine is not stopping I can use it, but I remember that the throttle after the middle, it was giving the motor a lot of power and now is not.
How can I check if a cylinder is not working ok, or a carb is not working ok, can I do anything? ( Perhaps half of the engine is not working ok, I don't know )
When I disconnect one spark plug what it will happen?
Is there a possibility that it is electonic ignition problem?
Do you have an idea how I check all these out of the water?


I dont know what is going on I have cleaned the carbs, I disabled the vro ( I was shure that it was vro problem but it wasn't ).

I don't know where to look and search, and the problem is that when I have the boat out of the water at my house, I cannot check this because it must have load and put the throtlle to full to check.....

Another question, inside the motor the plastic part that is mooving from the throttle on the console , mooves the flaps of the carbs ( if i say correctly ) and also some joints that goes on the upper part of the engine, ( under the spinning part )what are they doing?
Is there advance in this engine can I regulate something else?( I don't know the terms to descibe )

I hope you had understand me, sorry for my English

Thank you in advance
Leonidas

 

[wilde1j]

Re: Vro pump Jonhson 1996 40hp modification

when I press the choke the motor getting better and the rpm are rising, All this time I press the tanks primer bulb and it is firm meaning the carbs are full of fuel.

Leonidas

Try this:
FUEL PUMP OUTPUT TEST

1) Pull the safety lanyard so the motor can't start
2) Disconnect the pump outlet hose
3) Crank engine ... should get long strong spurts, any less is reason to replace/rebuild

OR

Put a pressure gauge teed into pump outlet line ... should read ~ 3 to 6 psig on a good pump with engine running.

If the pump doesn't pass the test, replace it.
Sierra 18-7353 has three hose nipples, one incoming fuel, one outgoing fuel and one for the hose for the pulse.

 

[leotzian]

Re: Vro pump Jonhson 1996 40hp modification

My friend thanks for the answer
I don't have a psi meter to check the pressure, but the pump delivers a lot of fuel

I checked for this pump you say, it says that is for 20-30hp mine is 40hp, is it ok?

I want to make you a simple question. When I press again and again the tank's bulb , I pump fuel myself, is this not the same than the fuel pump? I have continiusly the bulb firm, this is not meaning that the carbs have fuel in there pot's?
I have this problem and when I pump fuel myself using the tank's bulb ( external tank ), I tested that using another tank, same problem

Please solve my question

Try this:
FUEL PUMP OUTPUT TEST

1) Pull the safety lanyard so the motor can't start
2) Disconnect the pump outlet hose
3) Crank engine ... should get long strong spurts, any less is reason to replace/rebuild

OR

Put a pressure gauge teed into pump outlet line ... should read ~ 3 to 6 psig on a good pump with engine running.

If the pump doesn't pass the test, replace it.
Sierra 18-7353 has three hose nipples, one incoming fuel, one outgoing fuel and one for the hose for the pulse.

 

[wilde1j]

Re: Vro pump Jonhson 1996 40hp modification

If the pump is OK, then something else is preventing full fuel flow. Is there a fuel filter on the motor and is it clean?

 

[leotzian]

Re: Vro pump Jonhson 1996 40hp modification

Yes there is a fuel filter it is clean if I disconnect the fuel line from the filter outlet and press the tanks bulb a lot a fuel us coming out.

What else might preventing full fuel flow? I cannot imagine anything, have you an idea?If the tank's bulb is firm and hard don't this meaning that the carbs are full of luel, this motor will get me crazy


Please if you know answer my question..
Lets assume that the fuel pumb is not working, If I continiusly press the tank's bulb, is not the same thing?, the motor should working ok, is that correct or not??

The truth is that mice had get in the motor, cut me some cables, and fuel lines, but I have soldered the cables correctly, and changed all the lines......