Need help w/merc w/ no serial number

[Eldiablo]

I bought a rebuilt 200 black max merc from a dealer that I fought with for months after i bought it to fix problems. The motor still has idle problems and power problems (14.5 x 15 prop, should be running a 19 or 21 pitch) . anyway, i refuse to go back to this dealer and i recently went to find my serial number to get the year and found that there was none one the engine or the freeze plug. i've been told by guesses anywhere from '84 - '89. it oil inj v6, square cowling, . I can think of no information to give that would pin it down to a year. what info is needed? Thanx

 

[BKool68]

Re: Need help w/merc w/ no serial number

Did you purchase this motor from Almars in New Castle. He is the largest Merc. dealer on the East Coast. I am sure they could help you chase down the year. I would recommend replacing all the fuel and oil lines to insure you have no air leaks that could cause poor idle and performance.

 

[Eldiablo]

Re: Need help w/merc w/ no serial number

I bought it from beach marine that got the motor from almars. they helped me a little and got the yaer about, but i would like to know more exactly when it was built. i have not replaced the fuel lines yet but as i found out, that is what i should do after i finnish figuring out how to time this 25 johnson.

 

[BKool68]

Re: Need help w/merc w/ no serial number

Since it is a rebuilt motor it is likely to have parts from several years. I don't believe you will be able to nail it down completely. Most parts will probably interchange. I believe this motor uses a gapless plug so that won't be an issue. If your manual calls for a range of timing advance spes I would recommend the least listed advance setting.