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A New VRO Pump Question

WaitUpGuys

WaitUpGuys

Contributing Member
Howdy folks! I've search far and wide in the forum regarding the VRO pump and read through many threads regarding various VRO pump issues and also alternatives to go premix and bypass the oil pump altogether. I'm curious...instead of doing all of these cutting and plugging various hoses to bypass the oil pump and going premix...what about just keeping the VRO pump set up the same and have premix fuel in the oil containers as well as in the gas tank? Anyone see any risks? I'm I increasing my chances of a rouge spark causing me to blow up in the water? Are there diaphragms in the oil pump that could be sensitive to the presence of gas? Ideally, I like to keep the set up the same just in case I sell, the new owner can convert back. I am just trying to avoid dealing with a bad VRO and end up with another rebuild. This way, if the VRO is working, then i'm getting the correct mixture, if it's not working, i'm still getting the same mixture....thoughts?

Or is this a stupid idea? I am okay if you think this is stupid, just tell me why it's stupid. :)
 
You have done all this reading.-------But are you aware of how easy it is to take the VRO apart for inspection / repair.----------Nothing to it and you woulld then see how simple it is and how it works.------------Fill the oil tank with mix ????--------Not sure why you would want to do that.
 
I'll give the VRO a good look over and go from there. Thanks for your input. I don't think i have a pump issue. I'm rebuilding a 90hp crossflow and i'm just paranoid a pump failure will occur. Pump failuer is not the reason for the rebuild. A ring got caught in the port and broke off so it was bouncing around in the combustion chamber on the #1 cylinder head tearing it to kingdom come. Anywho, I will keep you posted...just in anyone cares.
 
dont take any notice of the rubbish written on continuous wave.
get rid of the stupid VRO. OMC knew it was a terrible idea and engines from new came with yellow plugs to turn it back to premix.
The vro idea was just to get through emission's for a while.
None of the RNLI or Navy or Army engines came with vro, they came pre-mix as they cannot afford break downs on missions.
do not ad fuel to the oil tank, just plug it off. very simple to do.
when the fuel side of the pump breaks (and it definitely will ) do not bother with a new vro style pump or kit, just buy the original style pump as thy last and are more reliable and a lot cheaper.

I have 2 vro pumps complete, and they both are total rubbish, to repair they cost far too much, and you are relying on a bad idea to keep your engine oiled as
it was originally intended.
I know 100% that my engine is getting 50-1 by going pre-ix, But with vro you cannot be sure what ratio you are using, it is impossible to get an accurate reading as
it differs far to irregular to get any sort of accuracy, I an be as little as 150 to 1 or as much as 50 to 1.. that is is far too big a range for an engine designed to be run
at 50 to 1 and even 40 to 1 if running flat out for long periods.
 
phillnjack said:
dont take any notice of the rubbish written on continuous wave.
get rid of the stupid VRO. OMC knew it was a terrible idea and engines from new came with yellow plugs to turn it back to premix.
The vro idea was just to get through emission's for a while.
None of the RNLI or Navy or Army engines came with vro, they came pre-mix as they cannot afford break downs on missions.
do not ad fuel to the oil tank, just plug it off. very simple to do.
when the fuel side of the pump breaks (and it definitely will ) do not bother with a new vro style pump or kit, just buy the original style pump as thy last and are more reliable and a lot cheaper.

I have 2 vro pumps complete, and they both are total rubbish, to repair they cost far too much, and you are relying on a bad idea to keep your engine oiled as
it was originally intended.
I know 100% that my engine is getting 50-1 by going pre-ix, But with vro you cannot be sure what ratio you are using, it is impossible to get an accurate reading as
it differs far to irregular to get any sort of accuracy, I an be as little as 150 to 1 or as much as 50 to 1.. that is is far too big a range for an engine designed to be run
at 50 to 1 and even 40 to 1 if running flat out for long periods.
Click to expand...

WHAT That is a bunch hooey from alarmists who want to blame all their problems on the oil pump. The VRO is a fine system that works well. People who don't understand it just bash it ,usually it's from people who don't understand how Internal combustion engines work. Replace the pump and have many years of happy boating. People who work on these motors and understand the system know it's a good system that works well.



Some people just won't let the facts get in the way of their thinking
 
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flyingscott said:
what that is a bunch hooey from alarmists who want to blame all their problems on the oil pump. The vro is a fine system that works well. People who don't understand it just bash it ,usually it's from people who don't understand how internal combustion engines work. Replace the pump and have many years of happy boating. People who work on these motors and understand the system know it's a good system that works well.



Some people just won't let the facts get in the way of their thinking
Click to expand...

thank you!
 
Its a pretty good set-up but the early VRO systems are iffy... so much that the OMC field reps called them Very Risky Oiling. The newer pumps after 1995 OMS as pretty reliable but still have some problems. If its a older pump with sonic welded tan nipples don't trust it, replace it with newer OMS pump.
 
The weak link in the older VRO systems was the crummy clear vinyl oil hoses. They deteriorated quickly, cracked and broke. The pumps themselves were reliable and last a long time. If yours happens to have the vinyl hoses get rid of them although I can't see how any of those junky hoses could last 30 years. Mine crapped out in 1989.
 
I never meant to start why the VRO system is good or bad debate. I know the first 2 yrs of the VRO were badly engineered the tanks leaked and bad lines. After that they had them worked out pretty good. As for Ethanol resistance nobody was making ethanol resistant anything in the 80s because it wasn't that common. I rebuilt motors from 1970 up to 1990 there was a big increase in rebuilds for me from all manufacturers motors from the late 80s to about 1995. A lot of it was because the ethanol was new and tearing up fuel lines and cleaning the garbage out of the tanks and going right into the carbs. At that time cars had steel fuel lines and good fuel filters so the effects of ethanol on cars was relatively minor. Outboards were another matter sometimes it was just a lack of maint from under educated owners which was OMCs fault for not informing the customers about care of the motor. Sometimes it was sh@t happens when you get garbage in the carb because the ethanol was cleaning out the lines and tank. That is just my 2 cents I always put the VRO back on put an inline filter on the fuel line and I never had problems with my rebuilds. I have read the Continuous Wave article I found it informative and intelligent and don't think it should be dismissed as rubbish. For me I think the late 80s were a perfect storm for crap happening to outboards or any 2 strk motor because so much was changing at the time. But I do believe people who understand the motor and the system are not the ones having problems with it.

Anyone remember the Mercury Auto-Blend System
 
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My 1985 70 HP Johnson came from the factory with vinyl hoses from the oil tank to the VRO pump and another short one coming off the pump. They were semi-transparent. Both hoses got brittle and failed. The first failure caused me to have to rebuild my power head. The second short hose was somewhat hidden so I didn't notice it until it failed as well. Fortunately that second failure did not cook my motor. Whoever selected that material for those early hoses made a poor engineering decision. I have been involved in manufacturing engineering and quality for 37 years and have seen the results of many bad decisions just like that one.
 
The VRO is critical in mixing 2-cycle oil based on fuel demand of the carburetors at different ratios depending on engine RPM....its not as simple as you think, it doesnt just mix at 50:1 all the time.....replacing the VRO will yield better performance and longevity
 
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