VRO - disconnect or not

[FishOn162]

I am sure this subject has been discussed, but searching "VRO" yielded no results.

I have a 1998 Johnson 90 with VRO. Bought used last year. This has low and no oil alarm.

I am very tempted to disconnect the VRO as a precaution.

One mechanic tells me I shouldn't, one tells me I should.

The engine is smokey at startup...not sure if this is a malfunctioning VRO or normal.

The VRO is working, oil is being used.

Please give me your thoughts and experiences...I am finding some say that disconnecting/plugging the VRO and pre-mixing causes rougher idle and increased carbon. Others say the engines run better with less worry.

How reliable is the VRO on this model?

[oldschool1]

disconnect, and you will have a fairly realiable outboard.

[SeaJay]

Most of those mid 1990's vintage Johnsons (I had one) never had any problems with the VRO. I think the bad rep of those things came from engines in the 1980's. It is a whole lot easier to just fill up the oil tank when low than to measure and mix everytime you go out.

[c_mccann]

VRO- Very Rarely Oils. Had one- either know how to maintain it yourself by a certified OMC mechanic or bypass it and run premix. Had one on a 140 Johnson and pissed through 4 powerheads in 2 years, found out it was a $2 part that was causing the problems- the mech forgot to check on each re-assembly... By the time I knew the system, I was over it, bought a 4-stroke.

[FishOn162]

Originally Posted by c_mccann

Had one- either know how to maintain it yourself by a certified OMC mechanic or bypass it and run premix.

Yeah...the "maintain" is what I don't like. I fill up with 5 gallon jugs...so it is easier for me to pre-mix than worrying about maintaining another system.

I really wanted to make sure there are no adverse affects to disconnecting.

After some reading I am assuming I need to do the following:

1. Pre-mix the tank for 50:1.
2. Run the engine a few miles with pre-mix and VRO connected to load up the fuel lines, filters, etc with pre-mix.
3. Cut the oil line to the engine, plug with bolt and hose clamps.
4. Unplug the wire lead from the VRO/fuel pump.
5. Trace wires from oil tank to engine, disconnect whereever the harness is.

[LI Sound Grunt]

Originally Posted by FishOn162

Yeah...the "maintain" is what I don't like. I fill up with 5 gallon jugs...so it is easier for me to pre-mix than worrying about maintaining another system.

I really wanted to make sure there are no adverse affects to disconnecting.

After some reading I am assuming I need to do the following:

1. Pre-mix the tank for 50:1.
2. Run the engine a few miles with pre-mix and VRO connected to load up the fuel lines, filters, etc with pre-mix.
3. Cut the oil line to the engine, plug with bolt and hose clamps.
4. Unplug the wire lead from the VRO/fuel pump.
5. Trace wires from oil tank to engine, disconnect whereever the harness is.

I think thats it. I wish mine wasn't disconnected but it is and I leave it that way - its a pain to mix the oil on the water. I can send a pic of how mine is disconnected if you want but there is TONS of info in the internet - try iboats johnson outbaords forum if your google search doesn't give you what you want.

Miine runs great by the way and also does smoke a lot sometimes at start-up.

PM me if you want a pic the boat is down at the marina..

[ioneyes]

Not sure if this helps or not...

http://continuouswave.com/whaler/reference/VRO.html

I have a 2002 J175PX that I noticed has started smoking (white) excessively at low RPM's. After researching many forums the consensus is there may be an air leak in my gas line. Read the attached link on misconceptions of a faulty VRO.

[LooseConnection]

Originally Posted by ioneyes

Not sure if this helps or not...

http://continuouswave.com/whaler/reference/VRO.html

I have a 2002 J175PX that I noticed has started smoking (white) excessively at low RPM's. After researching many forums the consensus is there may be an air leak in my gas line. Read the attached link on misconceptions of a faulty VRO.

Good Read! Thanks,

LC

[FishOn162]

Mine is not white smoke...it is two stroke oil smoke. Bluish. I understand that since the VRO mixes the fuel and oil before the carbs, after sitting fuel will tend to evaporate out and make it smoke from excess oil left over.

I fuel up with 5 gallon jugs...so pre-mix is not a big deal at all. Already adding stabilizer at each fillup...so what is one more fluid?

I mainly want to make sure that I can do this switch relatively quickly and I am not going to mess something up worse by bypassing. Going to try and do the switch Friday moring before the big weekend.

[epanzella]

Originally Posted by FishOn162

Yeah...the "maintain" is what I don't like. I fill up with 5 gallon jugs...so it is easier for me to pre-mix than worrying about maintaining another system.

I really wanted to make sure there are no adverse affects to disconnecting.

After some reading I am assuming I need to do the following:

1. Pre-mix the tank for 50:1.
2. Run the engine a few miles with pre-mix and VRO connected to load up the fuel lines, filters, etc with pre-mix.
3. Cut the oil line to the engine, plug with bolt and hose clamps.
4. Unplug the wire lead from the VRO/fuel pump.
5. Trace wires from oil tank to engine, disconnect whereever the harness is.

Good except #3. There is only one line to the engine and it carries mixed fuel and oil. You have to remove the oil line from the VRO tank at the INPUT to the pump. The pump is actually 2 diaphram pumps running off the vacuum pulses in the crankcase. The pump closest to the block is for fuel and the outer one is the oil pump. The short hose down the bottom brings crankcase vacuum to the pumps diaphram. BTW, a backfire will sometimes split this vac hose causing the pump to stop and you along with it. I ran an Evinrude 150 for ten years using premix only without a glich.

[Striper4]

Originally Posted by oldschool1

disconnect, and you will have a fairly realiable outboard.

That is what I did on my 1999 150 Ocean Pro and it has not failed me yet. I did have to replace a fuel pump however, in five years this thirsty outboard has performed fantastic.

[LI Sound Grunt]

Just to clarify the above post you do disconnect and plug the oil line to the VRO pump. There are a few lines to the pump. Here is another version of instructions form a boaters mechanics forum..

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 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 quanity 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.

[FishOn162]

Ed,

Sorry...I was talking about cutting the oil only line outside of the cowl...either that or pulling it off that outside of the cowl fitting and putting a cap on the nipple. Not the line from the pump to the carbs...rather the one from the tank to the actual motor.

Striper4...regarding replacing the fuel pump...I came across one thread from another forum where several guys warn against capping the later model VRO systems. That the pump (both oil and fuel) will fail afterwards. Was this your case?

I am thinking I may hold off until I can purchase a new fuel pump only and take the entire VRO assembly off.

At the same time, there are a TON of threads with folks saying not to remove the later model VRO's...that they are indeed reliable and their engine ran worse after removal.

I am at a loss here.

[LI Sound Grunt]

Originally Posted by FishOn162

Ed,

Sorry...I was talking about cutting the oil only line outside of the cowl...either that or pulling it off that outside of the cowl fitting and putting a cap on the nipple. Not the line from the pump to the carbs...rather the one from the tank to the actual motor.

Striper4...regarding replacing the fuel pump...I came across one thread from another forum where several guys warn against capping the later model VRO systems. That the pump (both oil and fuel) will fail afterwards. Was this your case?

I am thinking I may hold off until I can purchase a new fuel pump only and take the entire VRO assembly off.

At the same time, there are a TON of threads with folks saying not to remove the later model VRO's...that they are indeed reliable and their engine ran worse after removal.

I am at a loss here.

I advocate neither way. But...mine has been capped for probably 8 years and it runs fine. BUT premixing is a pain in the but when you keep the rig in the water. I looked into the fuel pump only option last time I replaced the pump but they did not make one for my application. I would have had to use a pure electric pump fit it in somewhere, and just did not want to vary that far from the original configuration. I bought a $40 used VRO capped it off just like mine was and that one has been fine for 2 years.

You will be fine either way.

[Bullshipper]

A variable ratio oiler was installed on your engine for a reason.

I had this same model and is now has close to 4500 hrs on it.

It also does not produce fouled plugs idling for hundreds of hours or white plug tips when running at 5000 rpms.

The diaphram is a cheap part to replace, and easy to do onboard, even though mine never needed it, running on Mexican gas.

If you had a problem with your VRO or your motor, I would consider this. But as they say, don't mess with it if it ain't broke.

[KeyPineSavage]

Like LI Grunt, I will advocate neither. And I will say that if the oil function of the VRO fails and your alarm system is not in good order, that is the end.

However, the one I had much experience with was a '97 115 powerhead, which I ran on its original VRO through 2006 when I sold the boat, and as far as I know the new owner still runs that way. It was a totally trouble free system for me. Only time I ever had to screw with it was if I had to remove a hose or hoses for some other reason (engine work a couple of times.) Then would run premix too for an hour or so, to verify VRO operation. For me, like Bullshipper, the VRO was great, and premixing is a PITA compared to a reservoir.

I too think it was the early systems that gave them their bad name. I guess I'd never disconnect one that was working well. But you MUST make sure the alarm system is functional.

[epanzella]

Originally Posted by FishOn162

Ed,

Sorry...I was talking about cutting the oil only line outside of the cowl...either that or pulling it off that outside of the cowl fitting and putting a cap on the nipple. Not the line from the pump to the carbs...rather the one from the tank to the actual motor.

Striper4...regarding replacing the fuel pump...I came across one thread from another forum where several guys warn against capping the later model VRO systems. That the pump (both oil and fuel) will fail afterwards. Was this your case?

I am thinking I may hold off until I can purchase a new fuel pump only and take the entire VRO assembly off.

At the same time, there are a TON of threads with folks saying not to remove the later model VRO's...that they are indeed reliable and their engine ran worse after removal.

I am at a loss here.

While I had no probs at all with my premix setup, this was on a 1988 Evinrude 150 which I ran untill around 1999. It was still running strong when I sold the boat. But this is old news, as I haven't run a 2 stroke since, so take it for what it's worth.
Pro- It's impossible to run out of oil when it's in the gas.
Con-You will burn more oil and smoke more at low speeds with premix, as the VRO's purpose is to vary the oil flow according to load.
Do your research and go with your gut.

[c_mccann]

The premix- I used to fish with a guy that pre measured his premix in re used dryed Evian bottles- whatever oil incriment for X amount gallons of fuel. He stored them on board, would load on X amount of fuel, dump one in. Much cleaner. Epanzella has a point- bring extra plugs, might be prone to fouling.

[LI Sound Grunt]

Originally Posted by c_mccann

The premix- I used to fish with a guy that pre measured his premix in re used dryed Evian bottles- whatever oil incriment for X amount gallons of fuel. He stored them on board, would load on X amount of fuel, dump one in. Much cleaner. Epanzella has a point- bring extra plugs, might be prone to fouling.

Couple of points here -

I have a 1998 225 hp ...in a slip....currently with the VRO disconnected - and again I am sure you are OK either way...

1- When you add some oil then some gas to the boat tank on land you trailer the boat - stop and start and vibrate a lot an dgo aorund curves and so I am sure the mix sloshes around a lot and it mixes will. I wonder if it does that as well on the water..... I have tried to blend the stuff with a tube in the filler neck as the gas flows in - also very awkward. Do you think the add gas then add oil on the water is sufficient to get everything mixed? Even on land I usually mix a gallon of the oil in a 5 gallon gas can and slosh it around before I add it. Maybe I am over reacting

2. I have never had fouled plug problems - BUT I do make sure I do some near full throttle operation before coming in. Also, the synthetic blends are pretty clean.

3. The actual VRO used to vary from 50 to one to 150 to one at idle. the newer ones (according to the article above) vary from about 50 to one at hi speed to slightly mare than 60 to one at idle. There really isn't much variation anymore. Some article I have read claim there is no variation with speed anymore.

"Since 1993, the VRO is actually called an oil metering system (OMS). The ratio averages about 60:1, slightly leaner at idle and slightly richer at full throttle. The older pumps idled between 150:1 (prior to 1990) and 100:1 (1990-1992), then richened up to 50:1 as the engine load increased."

Interesting that the factory idle mixture has become richer over the years....Wonder if this is experience...or better motors or bettter oils?...

4. Its raining - can't you tell.....

[joelfishman]

I had a '96 200 ocean runner, it quit pumping oil, no alarm, and my engine burnt up. A mechanic friend of mine told me they had the VRO problems solved by '96 and there was nothing to worry about. Well, it bit me in the ass.