Rebuilt 1988 Evinrude 150 V6 No Serial Number/ What brand oil and additives to use?

[BDigital]

I purchased a boat that has a rebuilt 1988 Evinrude 150 V6. I can not find the serial number. From what information I can gather the serial number is supposed to be on the starboard side of the engine. I can't find it at all either side. Is this common for rebuilt engines? I am aware that before posting a question I should have this information. Is there another place under the cowling that I can find it? I really would like to know what brand oil I should use to mix and what other additives? I am in CA. and they use ethanol in the gas here. I do have a basic shop manual that covers multiple years it recommends using 87 octane.

[ChampioNman]

Motor model number and serial number will be on the PORT side of the motor bracket on a small tag. 87 octane is fine, if the VRO is disabled premix at 50:1 ratio with a good TCW-3 oil. If your VRO is still connected I recommend either BRP XD-50 or Mercury Quicksilver Premium Plus both are synthetic blends and are available at you local dealer in bulk. I would also add Startron's Ethanol treatment or Evinrude's 2+4 fuel treatment. On a new rebuild you need to make sure that the 10 hour breakin has been completed, this should be a double oil process.

[BDigital]

IMG_0031.jpgIMG_0033.jpgIMG_0032.jpg As you can see from the photos the model number and serial number tag has been removed. I can see the wholes where it is supposed to be attached to the motor bracket. The VRO is disconnected. It currently has a 1/4 of a tank full of double oil mixture and has not been run through the break in process. I plan on doing that this winter. This is my first bass boat so in the process of learning how to drive it I'll be breaking it in as well.

[ChampioNman]

Don't believe it is an 88 then as OMC used decals and not metal tags in 88. The decal was attached to the large flat bracket and not the mounting arms. There should be a welsh plug on the top right side of the block this will have the serial number on it. Unfortunately in your case a serial number won't help as BRP flushed all the old data prior to 1996. If you can snap a few pics of the motor cover that may help ID the year. On the other hand you could very well have a 1988 powerhead on any 198x mid-section.

[BDigital]

IMG_0035.jpgIMG_0039.jpgIMG_0040.jpgIMG_0041.jpg I hope this helps. If you need more let me know. When I bought it I was told that it was a rebuilt Rude 150 v-6

[ChampioNman]

Wow that is stealthy! Looks more like a 200 motor cover. Now we need some motor pics.

[BDigital]

IMG_0048.jpgIMG_0049.jpgIMG_0051.jpgIMG_0052.jpgIMG_0054.jpgI have more pictures but the file size is to big. I can email if you like or post to photo bucket. There is a stamp on the inside of the cowling that says E-200.b_digital's Library | Photobucket Photo bucket url.

[ChampioNman]

Yep could very well be an 88.