I bought an '87 Astroglass bass boat from a neighbor a few months back.  It has sat out in a field by his house for about 12 years.  He said it ran good when he parked it.  I know it is a total gamble, but he sold me the boat, outboard, and trailer for $300, so I bought it.  

 

The outboard shows that it is a 100 HP engine, but I can't find any of the typical markings to positively identify it on some of the parts sites online.  I've looked at the engine and all I know right now is that it isn't froze up (I manually turned it over after lubing it) and that I need to replace all the fuel lines.  The lines between the carbs literally fell apart.  I need to identify the motor so I can buy some of these dry rotted parts so I can see if it will run.

 

I'm hoping somebody can give some advice on how to identify which motor I got.

 

Here is a link to a few photos: https://photos.app.goo.gl/5oFBwg7DDJBXLhBs8

 

I’d give Mercury a call as I believe Mercury /Mariner were the basically the same, just badged differently. Maybe @Way2slow or some of the knowledgeable BR contributors will see your thread and be of help. Good luck on your project and keep us apprised of the progress.

Try this link. 
 

https://www.crowleymarine.com/mercury-outboard/359.cfm?mdl=VVRZEW
 

 

Nope know very little about them.  Mariner was the salt water version of a Mercury.  Normally the serial number is used to determine the model year, but other than model number, don't have clue how to determine HP.

Sitting that long, the whole fuel system will need to be gone through and carefully inspect all the lines for dry rot, hard and cracked.   Water pump impeller must be replaced, it will be too hard and have too much memory to properly pump.  

The next thing is inspect all the wiring and make sure the insulation is still good and not cracking off.  If they are dry and cracking, you might be able to paint them with liquid tape and salvage them.

 

If you call or email Mercury with the serial number they will most likely be able to tell you the year and HP on it!  I have contacted them twice about my motor so I get the correct parts for it and they just ask for serial number and give me the exact part numbers I need for it!

My problem is that the parts sites have ranges for those years and they don't match the serial number on that tag.  I've searched the engine over for any numbers I could find stamped on it and none of them matched either.  

 

I looked at the Crowley Marine site that Ski213 posted.  It looks like the engine I have, but the serial number ranges don't match up on it either.  Should I just ignore the serial number ranges?  Is it common in this area to not find a serial number?

Call Mercury, and find out what you have before trying to do anything with it.

That old, it's possible it's had another powerhead on it.  They generally either stamp in into the aluminum block or in a disk that looks like a freeze plug.  I looked at this 2005 4cyl 90 block I have and they just stuck a bar code label on it, which can easily be destroyed.

That motor is from way before 2005.  1985 would be more believable.  Isn't this info on the title?

Is the engine a inline 6? 

Mercury partnered with Mariner for export engines. That era is more then likely mixed fuel 50-1, carburetor type, the carbs need rebuilding.  the owner should be able to answer some of your questions. These engines need fresh power packs so info is needed before tearing into anything. Removing spark plugs may help to see the  condition of cylinders using a scope.

The prop should also have numbers to indicate pitch. 

If mice/rats haven’t destroyed the wire harness that is a plus. If the boat was covered without standing water inside that is a plus.

Good luck,

Tom