New Owner Advice - '94 75 ELPTO

[guitarplaya39]

Hey guys, new boat owner here and I have a few questions/concerns.
I recently acquired a new-to-me '94 Bass Tracker with a Merc 75ELPTO 2-stroke 3 cylinder. Super low hours - garage kept since new and the previous owner even did the annual PM even though he never used it.

1. Rough/Jerky idle - The carbs were just serviced before I got it (cleaned, new jets due to sitting for so long). It "pops" a lot during idle, and you can feel it in the steering. I've read a few things about this... Low speed jets dirty, electrical issues, and "that's just how this motor behaves". Anyone have more insight on this?

2. Oil injection - I know general consensus is to just disconnect the oil reservoir and pre-mix the fuel, however, I've also read that the system in this engine is pretty reliable. The engine was used more just before I got it, and I've only run one tank of gas so far and the oil injection seems to working fine. Can anyone attest to the actual reliability of the system?

3. Aftermarket Temp Alarm - The oil level/overheat alarms do not work. I know the oil alarm failure is common and it was disconnected before I got the boat. While I was on the water recently, the alarm started chirping and squeaking, then it just stayed on constantly. The engine is not overheating and I know it's some kind of electrical issue. I can't seem to find a short anywhere. I'd feel more comfortable with a separate/independent overheat alarm anyway. Anyone have any suggestions? Where would I mount a new temp sensor?

Sorry for the long post and the old topics, I just wanted to know if anyone had more or updated advice about it.

Thank you! This forum is great!

 

[racerone]

You have installed a new impeller I hope.-------The oil injection pump is driven by a plastic gear on the crankshaft.----I have seen failures ( stripped teeth ) on those.----There is an oil output test that can be performed to put you at ease with these units.---I do not believe that oil pump has a failsafe warning buzzer on it.-----Low oil in the reservoir yes but nothing on it should the oil pump stop turning !----Do a compression test for future reference.----Post your numbers here.

 

[guitarplaya39]

You have installed a new impeller I hope.-------The oil injection pump is driven by a plastic gear on the crankshaft.----I have seen failures ( stripped teeth ) on those.----There is an oil output test that can be performed to put you at ease with these units.---I do not believe that oil pump has a failsafe warning buzzer on it.-----Low oil in the reservoir yes but nothing on it should the oil pump stop turning !----Do a compression test for future reference.----Post your numbers here.

Thanks for the response! Yes, new impeller. The old one actually still looks brand new so I kept it as a spare. An oil PUMP warning buzzer would be awesome. Do you happen to know how to perform the oil output test?
Compression is around 135-140 across all cylinders.

 

[racerone]

Yes I do.----But it would require too much typing.------The factory manual has easy to understand instructions.-----And you could also remove oil pump to inspect gear on the crankshaft with an adapter on a phone these days.

 

[flyingscott]

I disagree with disconnecting the oil injection on those motors. The 3 and 4 cylinder motors have good systems that generally do not fail. Change your waterpump impeller every 2 yrs and go boating. I do agree with getting the manual and checking it.

 

[guitarplaya39]

I just found the service manual and the oil pump test instructions. I know it's currently working though. Might try to inspect the gear when I gain the confidence I won't screw anything up lol.