Removing Oil Injection from your motor

Burty

Senior member
Joined
Mar 31, 2004
Messages
6,347
Location
Weston Super Mare
I know a few of you lot on here have been talking about removing the self oiling system on your motors. i found this and thought it might help

Oil Injection System Removal

The mercury oil injection system is a popular item to remove, especially given its reputation for failure, and inability to deliver reliably after 6500 rpm.

Remove oil resevoir, oil pump, mag pickup, pump drive shaft, then install plug in shaft hole. Remove oil hose off bottom of vapor seperator, plug hose, remove fitting on starboard side of the block where oil tank pressure hose is coming from, plug hole with pipe fitting either 1/8 or 1/4., Remove oil alarm box, and i think that's all. the plug for the pump shaft hole you will have to get from dealer. (12)

Mercury part number for the plastic block off plate is 43453 and the O-ring for that kit is 32509. Jay Smith Racing Engines also has a billet kit for doing this.

Finally it is recommended by several sources, that you keep the old oil pump gear on the crankshaft, as it provides crankcase volume, and if removed will cause that cylinder to be lean.
 
Is there an easy, surefire way to tell if your oil injection system is working properly? (i.e. without pulling it apart and measuring flow like it says in the manual)

I'm assuming mine is working OK due to the fact that the oil level drops & there's a film of sh1t all over the transom after each outing, but it would be nice to be a bit more precise.
 
It's a pretty basic system - IMHO it generally works fine, until it all stops completely in one go and lunches yer motah. The bit that fails is the plastic gear on the crankshaft, which drives a metal gear on the oil pump. The plastic teeth shear, and you instantly have no oil. :cry:

Since I'm a cheapskate, on my old motah I took the oil pump drive shaft out and ground the teeth off. Then put the shaft back in and made a plate to replace the pump. You need the shaft to be left in there to stop the bearing in the block from falling out and destroying the motah. Did everything else as burty said (still got a pile of bits in my garage, anyone want an oil tank?)
 
Matt said:
It's a pretty basic system - IMHO it generally works fine, until it all stops completely in one go and lunches yer motah.

So basically what you're saying is:

You know it's working OK, cus your engine is running OK.

You know it's not working OK cus your engine momentarily screams with pain & then dies.

:laugh:

That's cool, best I just don't worry about it too much then. :D
 
Well, I think the alarm monitors oil level in the header reservoir and also the pump shaft turning. So the alarm should go off when the pump stops turning.
 
On the earlier versions (Dunno if its changed since) You used to get those silly pip pip on ignition on self test but the actual warning was for the oil tank only. Low level (engine mounted one). Didn't do diddly else.
The damm thing kept going of when running due to the motion of the cat, sponson to sponson just kept setting the thing off., Jumper link soon sorted that :wink:
 
BluFin said:
On the earlier versions...actual warning was for the oil tank only. Low level (engine mounted one). Didn't do diddly else.

I'm pretty sure mine (1992) is for tank level only.

You're right about the bleep. Anything 1/3 tank or less in the rough & it bleeps on each wave.

Bleep...Bleep...Bleep...Bleep...Bleep...Bleep...

Drives you bloody barmy. My solution is to keep the tank topped up.
 
I believe the oil reservior float is wired in tandem with the oil pump sensor, so when the alarm sounds it's either low oil (float) or no oil (pump)!
Either way, if your going balls-out, chances are you ain't gunna hear the alarm, what you will hear is a fecking great bang !!!
Do away with the oil injection, go pre-mix.
 
Never bloody hear a thing when flat out.... I had the Overheat on a red strobe + & fixed Red & connected to a car horn still never heard the thing !!!!
 
xact-a-mun-do. Nuf said. :cry:
TheOrs, please take note!
 
Matt said:
... So the alarm should go off when the pump stops turning.

Yeh, it should. It's wee magnet which passes a hall effect sensor. If I remember correctly, and it's possible I don't, the magnet can fall out if the oil pump is removed.
 
Wayne Kerr said:
xact-a-mun-do. Nuf said. :cry:
TheOrs, please take note!

I can hear my oil alarm clearly, even flat out.

What you have to bear in mind is that my flat out is a bit less flat out than you guys' flat out. ;)

My boat is used for low speed leisure stuff; skiing mostly. I'll take the risk I think.
 
TheOrs said:
I can hear my oil alarm clearly, even flat out.
Blimey ,,,, sounds like you need to remove it NOW!
Pre-mix rules ,,,, OK.
 
My engine is a 97 Mercury 150 xr. I am seeing a lot of info on removing the oil injection system, which I was about to start doing. My alarm started going off the last time I was in my Whaler and my power was limited to under 1600 rpms. I deduced that the alarm was not coming from the under hood oil tank. I followed the oil pump wiring and unplugged the blue/white wire coming from the pump to the electrical sensor (black box) and the alarm stopped sounding. My question is: why disconect the entire system along with the oil pump plug when this in essence fixes the problem (other than not having that particular alarm any longer) if I am sure that the pump is delivering oil to the engine. Maybe I am not seeing something else that could go wrong by doing this because it seems way to simple. Is there something that could go wrong by doing this that I am not seeing?
Thanks
 
Back
Top