150hp, 2.5L carberated 1998 2 cycle compression

[jerryyow]

I just purchased a used 150hp, 2.5L carberated 1998 2 cycle engine, and wanted to know what the compression should be??
Also the oil injection was inoperative, and I was told to use 50/1 oil mixture.
Questions:
1. Should I remove the oil metering pump and shaft or is it ok to leave it??
2. Lower port side cylinder reads 90#, all others 110-115#, should there be any concerns??
3. Temp is 160F at idel, drops to 120F at anything over 1500RPM, is this normal to run cold at <RPM's??, is there some sort of bypass of theromastats at higher RPM's??
4. Running a Ron Hill chopper 26"P, engine turns 5800RPM@63MPH on 19' Bass boat, what is the RPM range for this engine??
5. Is there a engine shutdown system for high tempeture due to lack of oil in fuel, or falty water pump??
6. If engine were to be subject to low oil conditions, besides overheating of cylinders, would the bearings be at risk??
Engine runs fine on premix, just needed to know the specks on this engine, and any warning/safety things for this model engine besides the beep beep alarm.

 

[Faztbullet]

Re: 150hp, 2.5L carberated 1998 2 cycle compression

Compression is usually around 95-110 psi on these as they have the comprtession relief slot in sleeve. Compression will actually increase with operation.
1=yes and install block off plate or reinstall pump to plug hole
2= no within 10% do a decarb and see if it picks up any
3=Yes this is normal the way water is routed on this engine.
4=Rpm is within range but you got a lot of prop slip if only 63mph
5= No only alarm beeper alarm under dash
6= Bearings ,crank, piston and every moving internal part in engine will suffer if you has a lack of oil failure. Change impeller once a year,check lower unit oil once a month,run a good TCW-3 brand name oil,use a mixing cup to measure added oil(too much oil can be as bad as to little)run a good gas(87) with no ethanol added.