Stripping down a merc 90.

[steviecops]

Hi<br />I have a three cylinder Mercury 90 from the late 80's or early 90's, (haven't got the serial number to post yet).<br />I bought it as running but noisy, suspected bearing noise. Anyway, I want to get an idea if stripping this motor down to investigate is within my capabilities, so I need a few questions answered if possible.<br /><br />The motor is a lot heavier than I expected and moving it around is a real problem. I'm almost tempted to just sell it on as it is, but I'd really like to have a go at repaiting it.<br /><br />I've heard that re-installing pistons can be a pain on some Merc engines and that special clamps are required. Do I need these clamps for this motor or is there another method that can be used?<br /><br />Are these motors any more difficult to work on than other motors? I haven't got a manual yet but will invest in one if I take the job on.<br /><br />Thanks in advance for any info.<br />Steve

 

[WillyBWright]

Re: Stripping down a merc 90.

The inline 6s need those clamps. Yours shouldn't. Stripping it down is no biggie. Getting it back together is a lot harder, but shouldn't be nearly as hard as if it were a 6-cylinder 90.

 

[steviecops]

Re: Stripping down a merc 90.

Thanks Willy.<br />Are these engines prone to bearing trouble? I've been tole the eengine runs but is a bit "rumbly".<br /><br />Thanks<br />Steve

 

[rodbolt]

Re: Stripping down a merc 90.

that motor,if the bolts are not stuck, is easy to dissasemble and reassemble. buy the merc manual and not the aftermarket one. and the usual problem is a bad lower main due to water intrusion.<br />happens to all makes.

 

[Zamboni]

Re: Stripping down a merc 90.

Get that serial number steviecops...I might have the manual in pdf format to send over.

 

[steviecops]

Re: Stripping down a merc 90.

Thanks for the help. I've decided to do what needs doing over the winter. Just got to figure out how to get the motor up to my shed at the end of the garden! It's so much heavier than anything I've had before.<br /><br />Zamboni<br />Thanks for the offer. That would be a great help. I couldn't find any plate on the transom bracket anywhere but I found a number on an aluminium plug on the block that I think is the serial number. It's B 175245. Hope that helps. My email addy is steviecops@aol.com<br /><br />Thanks again<br />Steve