VRO or CRO How do you know which is which?

[thundakitty1000]

Father in law has a 1996 35 hp Johnson. Previous mechanic removed oil injection, father in law doesn't like to mix oil. My question is what type of oil pump does this motor have : a VRO or a constant ratio . Did these motors have injection problems? I have all the parts that they took off. Should I leave them off and deal with it or put them back on. How do you know which one is which? Thanks

 

[d.boat]

Re: VRO or CRO How do you know which is which?

It's "OMS" (oil metering system), not CRO.

Anyway, this article will be helpful to you in the terminology (VRO, VRO2, OMS), understanding the system and identifying the oil pump that's on there.

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

You'll get opinions both ways (pre-mix or not), but make up your own mind.

Me? I personally think the VRO/OMS pumps, if properly installed and with the minor maintenance that is required, are easier and more fool-proof than pre-mixing. I've pre-mixed for years, and years, and years, and used to think that pre-mixing was easy enough and more reliable. But I am sold on VRO/OMS and have even invested $ in restoring/updating my system. I believe it is more reliable than me mixing variable quantities of oil in variable quantities of fuel in my built in tanks. I have made a few mistakes in pre-mixing through my lifetime and there's a good chance that a good working VRO/OMS system would have never made a mistake in that same time period.

But that's just my opinion, there are others!

 

[wilde1j]

Re: VRO or CRO How do you know which is which?

^^^^

Agree

 

[thundakitty1000]

Re: VRO or CRO How do you know which is which?

thanks

 

[boobie]

Re: VRO or CRO How do you know which is which?

If this is a 3 cyl 1996 35 hp the mechanic did you a favor by taking it off. This is not a a vro/oms oil pump. It's basically what they used in the old accumix fuel tanks back in 1986. These oil pumps would mess up and you would end up with fuel in your oil tank and 3 scored cylinders in your mtr. A few years back even BRP was recommending to take off the oil pumps and mix your gas 50:1. I've experienced the scored cylinders with the oil tank having mostly fuel in it. These were great little mtrs but the oil system was useless. STICK WITH the 50;1 mix.