What to look for in used 1998 Mariner 150??

[4winnsskipper]

Looking at buying a boat with a mariner 150 horsepower, EFI two stroke outboard on it.

I will be running a compression test on it before i buy, but what numbers do i look for? I know they all should be within 10% of each other, but whats good? 115 psi per cylinder? higher/lower?

Also i will run motor on muffs and take note of the strength of the tell tale to indicate water pump impellar condition

what else should i look for when inspected this motor on this boat?

Obviously on water test is ideal but if not possible i need to know what else i can do to protect myself from buying a turd...i am mechanically inclined (rebuilt small block fords before)

Oh and i've seen this nifty quicksilver tool that plugs into motor and reads engine hours broken down by rpm, where can i get that? Or is it a $$$ tool only dealers have?

 

[starcraft1982]

Re: What to look for in used 1998 Mariner 150??

As for what to look for,1)compression definately(over 100,would ideally like to see 120s-130s)and(more importantly,yes,ALL w/in 10%of each other).Water from tell tale is important but unless youre on the water and can open her up,it wont,necessarily,be a "strong"stream.More importantly,its the temp of the water.should get hot,but not scalding.Take a thermometer and hold in the stream.The water flowing/not flowing is easy fixes.The temp(if too hot)may or may not be.And also would say possibly its been overheated before.Fuel injected motors are much more intricate than a carbed motor and w/that I,personally,would hesitate to buy if a full water test cant be done.JMO.Lastly,most anything CAN be fixed.Use your common sense,or better yet,take a knowledgeable person w/you.OUTBOARDS ARE EXPENSIVE TO FIX.dont bite off more than you can chew.Good luck!

 

[jerryjerry05]

Re: What to look for in used 1998 Mariner 150??

Compression,spark and fuel.Compression should be even or real close.
Spark use a spark tester.Look for a good bright spark.
Fuel,check for a seperating filter.Pull it off and look inside.Then check the hoses.Any soft or mushy or extra hard will be a problem.Squeeze ball too.
Make sure it's ran in a bucket or the muffs fit good.On a hose you ain't gonna get the flow so it might seem weak.But it shouldn't overheat.
The lower unit ask when it was last serviced.Then remove the drain plug and check the plug for water and chunks.It should have a small magnet attached,check for chunks of metal.ANY water is gonna mean a possible reseal.J

 

[ufm82]

Re: What to look for in used 1998 Mariner 150??

The Merc/Mariner 150 EFI's are great engines- very durable and robust. No carb issues like cleaning and messing with chokes when cold- they start easy and run great. Not much better on fuel than a carbed model but none of the issues.
If compression looks good, it starts and runs properly and everything else checks, jump on it. You'll not find a better engine out there.
Bear in mind that the pee stream on a Merc/Mariner only starts after the t-stats open up and that water will be hot but not hot enough to burn. You should be able to put your finger in the stream without burning yourself. Once the stats open, the water coming out of the prop should be warm but not hot. If the boat has a temp gauge that is a plus.
If you don't know the history of the engine and are at all suspicious, a water pump kit is cheap insurance against a cooling issue. With kits only running $75 for the complete kit it's an easy and fast fix that will give you peace of mind. Plus they are easy to install- with a little mechanical know-how or a manual if that is lacking, it can be done in less than 2 hours from start to finish.
Check all the wiring under the cowl and look for rub spots, hot spots or any other trouble points. If all looks good, buy it and enjoy it. These engines will run for a long time if given proper care. My '93 is in great shape and will push my 19' center console to 50+MPH. I've had it now for 4 years and apart from some basic stuff, it's been a great engine.

UFM82

 

[4winnsskipper]

Re: What to look for in used 1998 Mariner 150??

Anyone know where i can find the quicksilver computer tool that plugs into these outboards and diagnosis problems and gives the hour usage?

 

[Faztbullet]

Re: What to look for in used 1998 Mariner 150??

Ebay is best place and a good used one goes for about $800. CDI make one and its about $1600. That motor has the 82000 series ECU so it dont store any history, codes or hours, it just works or it dont.. The late 2001 and up motors with the "triple nickel" style ECM stores history.

 

[4winnsskipper]

Re: What to look for in used 1998 Mariner 150??

well ran compression test, came back great, all cylinders were between 125-130 PSI. Plugs looked good. Cracked lower unit oil plug and only got oil no water. Engine starts immediately, and runs great.


We had a hard time getting m muff's to seal around the water inlets on the motor so we would get only a drible out of the tell tale (water kept squirting out between the muffs and the drive big time, way more than it did on my volvo penta drive), anyone know a GOOD set of muffs with good clamping force and large cup surface area? (Im going to service the impeller no matter what just as added insurance)

Thanks guys im looking forward to owning an outboard, i was getting tired of changing bellows, and climbing around a tiny engine bay to change plugs, with my I/O!!

Best to you all