Removing oil injection

[ntarver0568]

1998 Mercury 150 Offshore
1998 20' Bayliner Trophy walkaround

The oil pump that sends the oil to the reservoir in the outboard has gone out and I want to do away with the oil injection system and start mixing it manually.
First, is there some sort of kit I should buy to do this or any instructions somewhere I can go by? Second, I don't know how many gallons of fuel my boat holds, it has about half of a tank in it now and I want to make sure I put the proper ratio. The guy I bought it from said it held 100 gallons, but my best estimation based on fueling it up in the past is that it holds 80 gallons.

 

[ntarver0568]

Re: Removing oil injection

Or would you recommend that I just replace the pump and keep the injection?

 

[dbrew]

Re: Removing oil injection

oil pumps are ok but they do fail sometimes if you want to mix gas, plug the hose out of the oil tank and start mixing you shouldnt have to do anything else you might want to remove the tank but thats up to you but when you go to sell it a vro is kinda a luxury that some like so keep everything hooked up but pluged or you might be foggin for skeeders this way if you want to run injection all you have to do is get a new pump and plug it in. Also i would unplug the oil warning alarm or everytime you go out it will buzz and drive you crazy.

 

[ramjer]

Re: Removing oil injection

1998 Mercury 150 Offshore
1998 20' Bayliner Trophy walkaround

The oil pump that sends the oil to the reservoir in the outboard has gone out and I want to do away with the oil injection system and start mixing it manually.
First, is there some sort of kit I should buy to do this or any instructions somewhere I can go by? Second, I don't know how many gallons of fuel my boat holds, it has about half of a tank in it now and I want to make sure I put the proper ratio. The guy I bought it from said it held 100 gallons, but my best estimation based on fueling it up in the past is that it holds 80 gallons.

I had my injection removed after major rebuild due to pump failure. I mix 1 qt oil to every 10 gal. of gas per the recommendation of rebuilder and have had no problems. He was also the one that recommended to do away with auto injection due to the problems with it.

 

[j_martin]

Re: Removing oil injection

The proper way to remove injection from that engine is to replace the pump with a block off plug that will keep track of the bushing in the engine. If you just cover the hole, that bushing could get loose and in the works.

 

[sschefer]

Re: Removing oil injection

The first question I must ask is how do you know the pump has failed?

 

[sschefer]

Re: Removing oil injection

1998 Mercury 150 Offshore
1998 20' Bayliner Trophy walkaround

The oil pump that sends the oil to the reservoir in the outboard has gone out

Do you mean that the upper tank is not filling with oil from the main tank?

 

[ntarver0568]

Re: Removing oil injection

Do you mean that the upper tank is not filling with oil from the main tank?

That is exactly what is happening. I keep having to take the cowl off and fill the oil reservoir inside the outboard manually every 15 miles or so.

 

[ntarver0568]

Re: Removing oil injection

I've had one person tell me that the oil injection system that I have in it hardly ever has problems and the alarm should notify me incase something goes wrong if I just want to fix it, but I bring this boat about 60 miles offshore on a pretty regular basis and I really would rather not having any problems to where I have to get towed in from out there.

 

[j_martin]

Re: Removing oil injection

That is exactly what is happening. I keep having to take the cowl off and fill the oil reservoir inside the outboard manually every 15 miles or so.

Well, your pump is working just fine. What's bad is there's a battery on top of the oil hoses, or the fifteen buck check valve on the lower starboard side of the motor block with the line to the oil tank attached is bad, or the cap on the boat tank is loose, or the air line to the boat tank has a leak......

Approximately 2 psi of crankcase pressure is sent to the boat tank, forcing oil up the other line to the engine reservoir. From there the metering pump pumps it into the fuel stream before the carbs or injectors.

The T valve doohicky just before the engine reservoir with the short piece of hose dangling from it is a valve that lets air in on purpose if oil is not coming from the boat tank, so the pump can get oil for about another hour at WOT. That's probably good. If it was stuck open there'd be oil all over the engine. If it was stuck shut, the reservoir wouldn't go down.

I would recommend for you that you take about a third of the money you were going to spend on an oil injection pump and spend it on a factory maintenance manual.

hope it helps
John

 

[sschefer]

Re: Removing oil injection

Well, your pump is working just fine. What's bad is there's a battery on top of the oil hoses, or the fifteen buck check valve on the lower starboard side of the motor block with the line to the oil tank attached is bad, or the cap on the boat tank is loose, or the air line to the boat tank has a leak......

To quote another famous poster.... Ayup...

And consider yourself lucky... This is an easy easy fix.