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delete auto oil injection 1998 mercury 175 sportjet or not?

road ranger

Active Member
Messages
7
Reaction score
0
Points
40
Boat Make
Sugar Sand
Year
1998
Boat Model
Tango
Boat Length
16
Can anyone give me information on my 1998 Merc 175 XR2 oil injection system? Can I block/delete the system all together and just run 50-1 premix without damaging the engine?
I would appreciate some input if someone has experience on this.
Thanks
 
Last edited:
Not sure if 50:1 is your mix for that engine, but I can tell you many early Yammies people did exactly this with no problems. In fact, it was better for the engine, as one of the hoses on the oiler had a tendency to break (which would then leave no oil in the fuel--no bueno for the engine). So I can't imagine that manually mixing to the same mix as your oil injector is set up to do would damage anything.
 
The answer is 'Yes', but the big question I have is 'why?' What problem would you be solving by undoing something the engineers worked so hard to perfect over the last 40 years?

Early on (in 2000) there was a recall for your Sport Jet XR2 175 to fix the Oil Injection system -- I'm attaching the Factory notice. It was a cheap (30 minute) repair but critical.

As long as that recall was done, you really should never have a problem with the Oil Injection system -- this is the same Oil Injection system that has been used on 100,000's of Mercury V6 outboards for probably twenty years and is considered highly reliable. Parts are cheap and readily available.

Another advantage is that this system increases the oil:fuel ratio when the engine is working hardest. Your engine will see 100:1 at idle and will increase to 50:1 at WOT -- why would you want to lose that? My 1999 Sugar Sand Tango 4+2 (also 175 XR2) makes hardly any smoke when idling at the dock because of the 100:1 ratio at idle -- switch to pre-mix and you'll smoke like crazy at low RPMs, and probably start oil-fouling your plugs.

Lastly, the ECM monitors both oil level in the tank and oil flow into the fuel line -- if either of these becomes a problem, you'll get an alarm. If you get an alarm, all you need to do is pour some 2-stroke oil into the tank to get yourself home and get the system fixed. To switch to pre-mix you have to disable the ECM, and then you lose your over-heat warning as well.

In any case, here are some ECM/Oil Injection delete instructions I found, but a LOT of what's in there is wrong. Use at your own risk. Also, the recall info is attached.
 

Attachments

The answer is 'Yes', but the big question I have is 'why?' What problem would you be solving by undoing something the engineers worked so hard to perfect over the last 40 years?

Early on (in 2000) there was a recall for your Sport Jet XR2 175 to fix the Oil Injection system -- I'm attaching the Factory notice. It was a cheap (30 minute) repair but critical.

As long as that recall was done, you really should never have a problem with the Oil Injection system -- this is the same Oil Injection system that has been used on 100,000's of Mercury V6 outboards for probably twenty years and is considered highly reliable. Parts are cheap and readily available.

Another advantage is that this system increases the oil:fuel ratio when the engine is working hardest. Your engine will see 100:1 at idle and will increase to 50:1 at WOT -- why would you want to lose that? My 1999 Sugar Sand Tango 4+2 (also 175 XR2) makes hardly any smoke when idling at the dock because of the 100:1 ratio at idle -- switch to pre-mix and you'll smoke like crazy at low RPMs, and probably start oil-fouling your plugs.

Lastly, the ECM monitors both oil level in the tank and oil flow into the fuel line -- if either of these becomes a problem, you'll get an alarm. If you get an alarm, all you need to do is pour some 2-stroke oil into the tank to get yourself home and get the system fixed. To switch to pre-mix you have to disable the ECM, and then you lose your over-heat warning as well.

In any case, here are some ECM/Oil Injection delete instructions I found, but a LOT of what's in there is wrong. Use at your own risk. Also, the recall info is attached.
Thanks for your assistance with this
 
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