98 225hp mercury "offshore"2 stroke

slydawg · Sep-13-2004, 06:46 PM

Hey guys!Just got a boat, an 83, 20'grady white with the above engine. Is this a good engine? Runs like a top. I just got the boat and have several questions.
First, I was warned against trolling with this large engine. Does this screw them up? Is slow trolling ok? I noticed it loads up at a 7-9 knot troll. It surges,loads up, which can be somewhat controlled with throttle adjustments.
I was told by some sketchy merc wrench that I need to "Run as high of an octane as you can". The manual states that none of merc's engines require "over 87". I would hate to fry the engine, but I would also like to save a wad O cash....
I read a thread about 2 stroke oil... West marine's oil is the stuff? Is there a way to buy oil in say, 5 -10 gallons to save a buck?
I use the PREMIUM PLUS merc stuff now, out of fear. Is it safe to switch over? I know merc would never advise it, so I want the truth.
Thanks
Sly

bertram31 · Sep-13-2004, 06:53 PM

Oil is a very disputed myth.All I can say is run a good quality oil.The bit with fuel,you wont fry you engine with 91 octane.The truth to that is your engine runs cooler with higher octane fuel.You wont hurt it with the 87 since the internal fuel burn temps arent that much more.You can put a trolling plate on your lower that flips down and covers the thrust from the prop to slow you down.This allows the engine to run at off idle and reduce your speed.
Jack

slydawg · Sep-13-2004, 06:58 PM

Thanks. That sounds clever. Actually, I was told that 87 would burn the engine? THat was my concern. Running these large outboads slow isn't hard on them? Interested to hear what everybody else runs.

**FULL TILT** · Sep-14-2004, 02:19 AM

dude- i used to have a 200hp merc offshore that was babied its entire life. only had 550 hours on the piece of shit, and it grenaded on me. regular oil changes (high quality oil), visits to the vet, sweet lullaby's at night couldnt keep the damned thing running. melted a ring, and that was all she wrote. called merc to ask if there was something they could do....NADA. i will NEVER, EVER buy a mercury product again.

repowered with a suzuki 140hp and put 350 hours on it in 2 years without so much as a hiccup. good luck bro!

slydawg · Sep-14-2004, 09:07 AM

I've heard good things too, but that doesn't sound too good to me....
I guess we'll see....

LizzieJane · Oct-09-2004, 11:37 AM

Use the 87, but use ring free or a similar product. Higher octane gas, with similar detergent additive, is not necessarily better for your engine. Higher octane gas is no more "powerfull", it just explodes at a higher pressure/temp. The compression and timing of your engine determine the proper octane rating. The book says 87. Assuming you're proped right and that you're not putting an excessive load on the motor with hole shots and a vastly overweighted boat for the motor, paying for the higher octane is wasting your $

Quote:

Originally Posted by slydawg

Thanks. That sounds clever. Actually, I was told that 87 would burn the engine? THat was my concern. Running these large outboads slow isn't hard on them? Interested to hear what everybody else runs.

87

**Ali** · Oct-09-2004, 06:57 PM

Take any questions to Bruce at Marshall Marine in Spring Valley.

He is the Merc masta and a cool guy.