1995 90 hp merc 2 stroke smokes ( white)

plugs are covered with oil cleaned them and the same thing (oil) on the plugs compression test 124-124-126 eng running rough white smoke fills the neighborhood backfires on decellaration and white smoke gets worse it feels like its missing a cilinder intermitly seems like its getting too much oil i dont know if it would be rings with the comp it has. this boat is new to me this was the 1st time i started it anybody have an idea what this could be. did i buy myself a 90 hp anchor.

Re: 1995 90 hp merc 2 stroke smokes ( white)

change your plugs to start off, check oil mixture or if its oil injected try running it with premix on gas can (fresh gas w/oil). you could also check carbs for clogs on jets.

Re: 1995 90 hp merc 2 stroke smokes ( white)

basshunter62 said:

plugs are covered with oil cleaned them and the same thing (oil) on the plugs compression test 124-124-126 eng running rough white smoke fills the neighborhood backfires on decellaration and white smoke gets worse it feels like its missing a cilinder intermitly seems like its getting too much oil i dont know if it would be rings with the comp it has. this boat is new to me this was the 1st time i started it anybody have an idea what this could be. did i buy myself a 90 hp anchor.

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White smoke and all the other symptoms indicate water intrusion. Most likely suspect is the exhaust/cover plate gaskets. This is the plate on the side not the one between the power head and the mid section.

It's not a big job to fix it. Shop time should be no more than 1.5 hours. I had it down to 1 hour on my 100. And yes, it is fairly common but not so common that everyone has the problem. If it becomes a repeated problem then the exhaust plate is warped and should be replaced.

Re: 1995 90 hp merc 2 stroke smokes ( white)

Does it seem to use a lot of oil from oil tank? Was it tuned up lately? If it is using a lot of oil ,remove the oil pump and check the rear seal around shaft as I have see these walk out and fill the lower cylinder with oil. If it was tuned up and started this check the fuel pump diaphram as the early models (93 and back) used a different fuel pump diaphram and could cause a problem if installed.

Re: 1995 90 hp merc 2 stroke smokes ( white)

the boat is new to me no idea when last time it was tuned il start with the plugs and carbs hang a remote fuel supply. do i need to do any thing to the injection system or just run it on like a 50-1mix when im checking the exhaust manifold is that for water or exhaust or oil. or will just have to pull it apart also if the rear seal on the oil pump si bad would that put too much oil in the cilinders o ya and also the fuel pump diafram thanks for all your replies i have some work to do so igot to get bussy

thanks to all from basshunter62

Re: 1995 90 hp merc 2 stroke smokes ( white)

Excessive oil will produce blue smoke not white. However, some fuel additives can make it smoke a bluish white.

Plugs can appear clean but oily (water and oil don't mix) during water intrusion. Pull the plugs and have a look at the tops of the pistons. If any are shinny clean then you have water intrusion and it's most likely where I told you it was before.

If you do find a shinny piston top, bear in mind that your engine does not have a traditonal head. The heads are cast into the block so there are basically only two reasons for it to occur, the exhaust cover is warped and the gaskets have blown out or from a cracked block.

It's really not a big job to fix it, it only looks intimidating. However, if you let it persist you will cause further engine damage since water is an uncompressable liquid.

Sorry if I seem adament about this, but when something only takes an hour or so to check and/or fix, it just seems wrong not to do it.

Re: 1995 90 hp merc 2 stroke smokes ( white)

thanks for your in put. i dident have any time this morining to do much with it . but i did pull off the front cover to take a look and there was a lot of oil witch looked to be comming out the carbs its realy wet in there