1999 150 hp

[GlasV162]

Hello,
I'm looking at a boat powered by a 1999 Mercury 150 2-stroke. What problems were common with that year, and what's the best way to check for them? Much appreciated.
Thanks
John

 

[Chris1956]

Re: 1999 150 hp

That is a proven design. The issue is whether that particular motor is in good shape. You need to check the compresion, see if it sparks on all 6 spark plugs and whether the gear oil is clean. If the compression is 100PSI+ and ever on all cylinders, that is good. If it has spark on all 6 that is good. If the gear oil is clear amber or some other clear color, that is good. Milky gear oil could mean a bad gearcase.

 

[GlasV162]

Re: 1999 150 hp

Thanks. How about the oil injection? Were they still using the plastic gear to drive the oil pump in 99?
Thanks,
John

 

[1nebel0]

Re: 1999 150 hp

Get rid of it no matter what....buy the Merc plastic plug, the two bolts and then the pipe plug on the starboard side and you can take it all off and never worry about is it getting oil again....

 

[GlasV162]

Re: 1999 150 hp

Hello,
One other question: this motor is the EFI model. What is the difference between EFI and OptiMax?
Thanks,
John

 

[Chris1956]

Re: 1999 150 hp

Lots of difference. EFI has injectors instead of carbs. Very much like the throttle body fuel injection the Detroit cars had for some years in the 80s. Air enters the throttle bodies, where gasoline and oil are sprayed into the air stream.

Direct injection motors injest only air and oil via the throttle bodies. This travels thru the crankcase as in normal 2 cycle motors, and then into the combustion chamber. After the transfer ports close, gasoline is injected into the combustion chamber. Optimax uses a pulse of air to force the gasoline into the combution chamber, hence the need for a compressor on the motor.

 

[GlasV162]

Re: 1999 150 hp

Any advice on a pre-purchase inspection? I put a deposit on the boat, with the sale contingent upon inspection. We now found out that the closest shop that can fit the boat into their schedule for an inspection is a 40 mn. drive away, and the seller is not willing to take the boat that far. He has offered to do a compression check with me there, at his home. Any thoughts on this? Thanks.

 

[Chris1956]

Re: 1999 150 hp

Pre-sale inspection should be proportional to the cost of the motor. Cheep motors get less look-see than expensive ones, IMHO.

I would recommend compression test, followed by letting a little gear oil out and look at it's color. Then fire her up on the muffs. If she runs, has even compression and the gear oil is clean, it is likely a good motor.

 

[GlasV162]

Re: 1999 150 hp

Thanks Chris