StripersOnline › SurfTalk › Stripers Online Forums › Boating Forum › 1989 mercury mariner magnum 2-150 hp
New Posts  All Forums:Forum Nav:

1989 mercury mariner magnum 2-150 hp

post #1 of 13
Thread Starter 
My father in law baught a brand new 1989 merc in 89, put maybe 30 hrs on it, and went ill in 1991, boat sat in garage since then, I was asked to pull boat out of garage last year, for remodel, to my suprise there is this 150 hp outboard on it, Under hood moter looks brand new, did a compression check and red as follows Left side top to bottom 130psi, 130psi, 120psi, Right side top to bottom 150psi, 145 psi, 120psi. the man who did the compression wanted to buy outboard i had listed for $2000.00, after test he offered 1200.00 saying something is wrong w/outboard. Any sugestions on what I should do to fix these compresion stats or should I just take what I can get for it.
Thanks M.
525
525
525
525
post #2 of 13
So the engine sits dry for how many years and he expects perfect compression??

In all likelihood, there is nothing wrong with that engine, it just needs to be run. Run and maybe decarbed and the compression should even out.
post #3 of 13
I agree with runnning it, you need to run it with a load on it to re-seat the rings, take it out for a day and take it easy at first then juice it up a few times, also 1500-2000 is decent money, 2000 if the compression comes back
post #4 of 13
Thread Starter 
Thanks Gentlemen I 'll probobly do repairs as far as new impellor, clean or rebuild carbs, flush lines, and new fuel pump, change lower unit gear oil and seal, then run it in Lake washington over here in seattle,Washington.
Happy Fishing and thanks again,
Mario
post #5 of 13
Before you turn it over to start. You should pull the plugs and spray Mystery Oil into the cylinders to loosen up the rings and to lube them back up. Hand turn the engine every day and spray in more oil. Seeing the engine has sat for almost 20 years things have to be stuck. Besides cleaning out the carbs and lower unit. Also drain what gas is in the boat and check to see what the tank is made of. Plus add a Racor filter system to the boat.
post #6 of 13
make sure the oil injection is working correctly and replace the 20 year old oil in the oil tank. That outboard is old technology but they run hard and strong. I would run premix in the beginning to make sure its getting oil.
They also tend to smoke alot at startup.
post #7 of 13
What jigger said is right on. In fact, it would have been better to spray MM oil in before you even turned it over.
But those numbers look good, in fact pretty high, and I'll bet they level out once you run her.
Do what you plan, and I'll bet you'll get many years out of it.
post #8 of 13
Thread Starter 
Hey Gentleman thanks for all the advice.
I did spray liquid wrench in all the cylinders a couple weeks before, and a couple days before I had a compression check, and manually turned flywheel, turned with ease both times, and all pistons were moving freely.
aprieciate all your advice!

M.
post #9 of 13
You should do the pre mix for a while rather than to bank on your oil injection operating properly. The most common failure on those merc's was the oil mix failure......leading to ineffective lubrication....over heat.....and so on. Doing the pre-mix will safeguard your units condition. Be prepared for that pump to fail. Most of them did on those outboards.
post #10 of 13
Thread Starter 
You guys are great and very helpfull thanks alot and again Happy Fishing.

M.
post #11 of 13
Hey - do you want to sell the engine?????

Regards

Jim Burans
post #12 of 13
Thread Starter 
My email is mariog207@yahoo.com. Posiibly sold tomorrow for ? postad for $2000.00 obo, email me with your offer before 3:30 Pacific coast time tomorrow, and lets see.
Thanks M.
post #13 of 13
Thread Starter 
sorry to the gentleman who asked if it was for sale,
sold as of today,
Thanks for your interest.
M.
New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: Boating Forum
StripersOnline › SurfTalk › Stripers Online Forums › Boating Forum › 1989 mercury mariner magnum 2-150 hp