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I am just in the beginning restoration stages right now and not close to firing up the engine. It is a 1984 Evinrude 90 HP with VRO.

The oil tank was cracked and I have a replacement I found but I do have fears with this system and would appreciate some guidance before I decide if the VRO tank needs to be reinstalled or left out. Right now I have empty corners in the rear of the boat where the VRO tank and batteries and bilge will all need to be permanently installed. The boat is a 1974 Montauk 17'.

Is there a way to test if the VRO is working right before I fire up the engine? I will of course replace the lines before I get to it. Is it better to just replace the original VRO to a new updated style. Taking the boat to the friendly marina mechanic over 100 miles away is an option I prefer to avoid and I am mechanically adapt and can perform most of my own repairs with some guidance.

I am in the planning stages of the boats interior and just don't want to install the tank and then find out I might have to uninstall it to get a new and different tank or even just to leave it out and mix the old school way. I sure don't want to learn the expensive way that my VRO is not working or pumping when I first fire up an engine that has been sitting for a few years.

I am kind of sitting on a fence here and not sure how to plan my attack on this project. Should I do the engine first making sure it is up and running before doing all the boat clean up and hole filling and installing all of the mounted items such as VRO tank, batteries and wiring or should I get the hull all ready and tackle the engine and permanent mounting at the end of my project?

Gary

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Once you install and fill your VRO oil tank with oil, go ahead and premix oil in your gas too. After running it for a while you should see a decrease in your VRO tanks oil level. Keep in mind your motor is going to smoke like crazy too as a result of mixing your oil in your fuel tank and using the VRO system......if the VRO is functioning properly.

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Thanks CES but I sure hope there is a better, faster and more reliable way to test the VRO system. Hope we have an evinrude/johnson mechanic lurking here who won't mind giving up a bit of knowledge on the subject.

gary

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Cliff's advice to premix is sound and reliable, it's failsafe.

Even if you do the test below, which is a "faster" version of what he recommended, I'd still want to be sure oil was getting to the engine in the event the pump isn't working during the duration of the test.

http://www.boatpartstore.com/vro.aspom/vro.asp

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Dave is right on.

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I still pre-mix my fuel. I had the VRO disconnected when I bought my engine new. I've been on many boats with VRO systems and NEVER have seen a problem with any of them. I don't use much fuel (04' Johnson 50 h.p.) and I like to mix the fuel because, that way I "know" the oil is IN there, and in my "pea" brained mind, it's one less sysytem to worry about breaking down. I also like to play "Chemist" when mixing the Gas, oil, and Sea Foam to see how perfect I can get the "Brew" (white Lab coat is optional).

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Thank you all. I suppose it is safe to say that I am not overly confident in the VRO systems at all. It might work perfectly fine but as others have pointed out here, I prefer to depend upon my self over any automated system that could fail and lead to catastrophic damages. I should make a decision very soon weather to use the VRO and install the tank or to just eliminate the tank and system all together. No need to drill new holes after refurbishing the deck for a tank I will not use.

Gary

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It is very difficult, if not impossible, to get the oil mixture just right if adding it manually.
A person usually get the mixture with too much oil and therefore the motors always has a tendency to smoke too much and go through more spark plugs.

The VRO (now OMS) meters the oil at different levels throughout the power range which would be about 80:1 at some speeds and 50:1 at other speeds. This usually saves oil, spark plugs, and less smoke at different speeds.

Mixing the oil manually, the motor always runs at 50:1 (or lower depending who is mixing) If a person always adds a little extra oil, then the mixture can obviously start getting too much oil.

Disconnecting the VRO to me is like disconnecting the Power Brakes or Power Steering on an automobile because if it goes out it might be dangerous and cause damage.
The VRO system is fairly bullet proof but should be checked for any leaky hoses or connections as part of your regular maintenance.

I hate mixing oil in the fuel and would never disconnect my VRO System.
I even added VRO to my kicker motor.
http://www.whalercentral.com/articles...icle_id=48

Everyone has their comfort zone.
Good Luck with your decision.

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In the Evinrude manual it states, anytime you disconnect the VRO system for any reason, you should always run pre-mix to make sure the VRO is drawing oil from the tank. After this is certain, then you no longer have to run pre-mix.

You might also read this article I wrote on the warning horn system.
Make sure your warning system is working properly.
http://www.whalercentral.com/articles...ticle_id=9

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Thank you Joe and I can certainly appreciate your feelings on this subject.

One major issue I am faced with has to do with geographic location and the severe lack of competent marine mechanics within a reasonable driving distance. I am sure many of use need to be DIYers for this reason. I will not repeat horror stories from others but this area seems to have plenty with the few local marinas where mechanics or those who call themselves such can be found. My other option is to drag the boat over to the Hudson river where I "Might" find a decent shop and mechanic but certainly at a high cost and also requiring leaving my boat for a week or more in a rather seedy part of the city. That would be about a 150 mile round trip twice.

I will get the manual. I am a fairly competent mechanic of sorts, (keep all my equipment running well) and properly maintained but some systems do strike fear in me. I should just get passed it and consider it is after all a 26 year old motor and could be old enough to think about updating any way. The worst I could do is blow it up and for all I know right now it could already be on the way out.

Gary

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A 1984 Evinrude has the fist generation VRO (OMS) mixing unit which was updated in 1991 and again in 1996.

I recommend that any OMC motor with the older system, where there is any doubt at all about its viability, be udpated to the newesy mixing pump.

This is not an inexpensive update and it may more prudent and cost effective to disconnect the VRO and run premix.

I agree with all of Joe's comments about the inconvenience and liability of pre-mixing the oil with gas, but in the case of a small boat like a Montauk, and especially one with twin portable 12 gallon fuel tanks, there is no reason to not be able to maintain a perfect mixture of oil and gas.

Larger boats with large internal fuel tanks offer much greater challenges for pre-mixing; I would not want to pre-mix the fuel for an Outrage 18 with its 63 gallon internal tank, for example.

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Thanks Tom. Just for the record, a 12 gallon tank is at least 100 pounds and at near 60 I won't be horsing many of those in and out of my boat. I am close enough to NJ that I can pull up to the pump and say filler up! I have 2 corners in the aft of my Montauk that will be nice for batteries and a bilge as long as I don't need to save room for a VRO tank. On another note, growing up, we always had to mix oil with our gas so it comes second nature. I have to allow for what Joe said regarding throttle Vs fuel/Oil ratios and all that comes with it but it served us pretty well back in the '60s and 70s and changing plugs is simple as compared to changing engines and top ends. I am leaning toward the tank being left out and the VRO heading south.

gary

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If you premix a little heavy, as some do to guarantee proper lubrication, it's not only the plugs that can be affected but the pistons and rings too. They get extra carbon build up as well over time, which can cause a number of issues. So it's best to decarb more frequently if you end up going the premix route and disconnecting the VRO.

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Gamalot,

I know what you mean about mechanics. I have about a 2 1/2 hour round trip drive twice if I take my boat in which I don't as I do everything myself except in a very unusual circumstance.

Mine has been updated once but as Tom mentions, I believe there is a another update.

On my prior Montauk 17' with a 1985 Evinrude 70 which I owned for 15 years, I had the VRO. I also had two 12 gallon portable tanks.
It is easier to mix, if necessary, by running the 12 gallons out of one tank and then putting in exactly 12 1/2 gallons of fuel to 1 quart of oil to give you the 50:1 ratio. As you can see, the 1/2 gallon doesn't exactly fit into the ratio as the tank only holds 12 gallons but close enough.
I still wouldn't have been without my VRO.

The 1985 Evinrude 150 that I have now is still running strong.
I have never had a problem with the VRO on any of the OMC engines I have had.
I also have never worried about the VRO as it has been a very reliable unit.
Just make sure your warning horn system is working properly.
You might also take a look at this article about adding a System Check Tachometer.
http://www.whalercentral.com/articles...icle_id=72

I did have an oil tank that malfunctioned inside the sending unit which set off the warning horn. I replaced the tank with a new one and haven't had any other problems. The VRO was still working, it's just that the horn was sounding due to the bad sensor inside the tank.

Most VRO problems have been diagnosed incorrectly and it has NOT been the VRO at all.
The myths get started by someones brothers uncle who had a friend that knew a backyard mechanic that said the VRO caused your engine to blow up.
HOGWASH...

If I ever have a problem with the VRO, I would replace the pump with the latest version available at that time.

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As Usual Joe and Tom are on top of things. :-)

A few years back, my VRO went bad on a 1989 OMC Sea Drive, and my alarm system functioned as it was supposed to and no engine damage resulted. The Alarm gave me the beeping code, my son, who was 13 at the time heard it and immediately cut off the engines before I could get to the helm. I powered then engine back up, verfied the problem and came in on one motor. @ days later I had the new VRO system in hand, installed and never had another issue. And yes, I was and still am proud of the boy and today he's 21 and a great up and coming technician for a Dodge, Chrysler, Jeep, Eagle dealer.

Bottom line, the system works, you just have to be aware of the operating characteristics of your boat and keep up with the maintenance.

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Not for nothing it's always a good idea to carry 2 stroke oil in case you have a problem. Some boaters don't have two motors and then what? Just pour it in and get back to the ramp.

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If you still "pre-mix" you can get the 50:1 measuring cup from the boat store. All you do is pour the oil into the cup up to the mark of "How many gallons of fuel added", and your oil is matched perfectly to you fuel. NEVER add a little more oil thinking that "This" helps in lubrication (as Dave pointed out) it creates hot spots and carbon build up on the rings, MIX IT PERFECTLY, keep it "right on the money", and add "Sea Foam" if your fuel sits in the tank for a while. I use "Sea Foam" or at least "Carbon Guard" (actually cheaper than Sea Foam because you use less) every time I add fuel. I had an old evin. 48 that we re-built, (it ate a ring) and I kept the chewed piston on my desk at work. An outboard mechanic saw it and knew what engine it came out of, I laughed and said "I guess I forgot to add oil", he said "No then it would be blue in color, you had carbon build up and the clip grabbed the ring".

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I beg to differ a bit on the point of getting your hand mix exact. Something Joe said earlier is quite true in that the VRO is a metering system and it probably does not provide a 50:1 mix over the entire range while running. How the carbs are adjusted might also dictate a leaner or richer hand mix in the end result. A good mechanic will make some observations of exhaust emissions and how the plugs are burning and make adjustments accordingly.

I would certainly keep the mix as close to 50:1 as possible but it really is not that critical if it gets off slightly. The VRO if working properly will make adjustments as required and is supposed to give the best ratio for the conditions while a hand mix is what it is and cannot be changed unless fuel or oil is added.

I have an Ice Auger for fishing that came with 24:1 mix ratio right on it and it ran very rich. The company, Techumse, published a new recommendation to change the ratio of all their 2 cycle engines to 40:1.

We have all seen the boat producing a thick smoke screen at the dock from running way too rich but this should not happen with a VRO equipped engine that adjusts for water and air temperature and throttle positions. 50:1 is a one size fits all recommendation where there is no one size fits all conditions.

Gary