Need help figuring out the year of my 3.0L Mercruiser Engine

firefighter014

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Can someone please help me figure out what year my Mercuiser Engine is? The serial number is A617689 and the drive unit number is OA637671.
 

Fun Times

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0A617689 belongs to a MERCRUISER 140, model number 01402006 which makes it a 1986 year model.

0A637671 = MERCRUISER MC1 1.98:1, model number 01989016.. 1986 as well.
 

firefighter014

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0A617689 belongs to a MERCRUISER 140, model number 01402006 which makes it a 1986 year model.

0A637671 = MERCRUISER MC1 1.98:1, model number 01989016.. 1986 as well.
Thanks.......any reason why it shows the fuel pump in the upside down position? my pump stands upright with the bowl up top. there seems to be a lot of confusion about this pump and the model years mounting positions. I need to be 100% certain before I order my new pump.
 

Fun Times

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Thanks.......any reason why it shows the fuel pump in the upside down position? my pump stands upright with the bowl up top. there seems to be a lot of confusion about this pump and the model years mounting positions. I need to be 100% certain before I order my new pump.
There are/were two designs for the fuel pump...One up one down and searching through the two pump designs in the parts catalog, the one that goes down suggests line modifications would be necessary so either make your own or possibly buy what's available under the facing down pump parts catalog item number 7,
Fuel pump mounted with filter bowl facing down
Fits 4 cyl. (2.5L, 3.0L & 3.7L) engines
NOTE: SOME OLDER MODEL ENGINES MAY NOT BE ABLE TO USE THIS PUMP WITHOUT MODIFYING FUEL LINES.

And while the facing up pump is technically no longer available, it seems Bam marine in Florida may still have 7 in stock though pricey compared to the facing down pump...Fuel pump mounted with filter bowl facing up
Fits sterndrive engines 120/2.5L, 140/3.0L, 470/485/488 & 160/165/200 (I/L 6 cyl.), https://www.mercruiserparts.com/bam/subassemblydetail/36079259/28146441

^Usually, you are able to click the Mercuiser part numbers for additional info to the parts you're interested in.

That mentioned, there's usually a scary, to low of a cost to be true/work correctly chance on eBay using the OEM part numbers, https://www.ebay.com/sch/i.html?_nkw=86234A05+&_sacat=0&_from=R40&_trksid=m570.l1313
 

Scott Danforth

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Your pump was supplied originally by Carter fuel systems to GM which supplied the long block to Mercruiser

Summit Racing has them for a reasonable price. Your local NAPA can also supply the proper marine fuel pump
 

firefighter014

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There are/were two designs for the fuel pump...One up one down and searching through the two pump designs in the parts catalog, the one that goes down suggests line modifications would be necessary so either make your own or possibly buy what's available under the facing down pump parts catalog item number 7,
Fuel pump mounted with filter bowl facing down
Fits 4 cyl. (2.5L, 3.0L & 3.7L) engines
NOTE: SOME OLDER MODEL ENGINES MAY NOT BE ABLE TO USE THIS PUMP WITHOUT MODIFYING FUEL LINES.

And while the facing up pump is technically no longer available, it seems Bam marine in Florida may still have 7 in stock though pricey compared to the facing down pump...Fuel pump mounted with filter bowl facing up
Fits sterndrive engines 120/2.5L, 140/3.0L, 470/485/488 & 160/165/200 (I/L 6 cyl.), https://www.mercruiserparts.com/bam/subassemblydetail/36079259/28146441

^Usually, you are able to click the Mercuiser part numbers for additional info to the parts you're interested in.

That mentioned, there's usually a scary, to low of a cost to be true/work correctly chance on eBay using the OEM part numbers, https://www.ebay.com/sch/i.html?_nkw=86234A05+&_sacat=0&_from=R40&_trksid=m570.l1313
Then the pump arm will be facing the wrong direction and possibly cause damage to the camshaft.
 

Fun Times

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Then the pump arm will be facing the wrong direction and possibly cause damage to the camshaft.
^ Gotcha to where in further studying, you're correct.

I did find one other note that brings up a past memory to some of my earlier thoughts above, (Many fuel pumps are used on similar engines. In order to identify the correct fuel pump for your application, you must check the “clock” position of the inlet, outlet, and separator fitting (where applicable) in relation to the rocker arm.)

To your situation 'the following used black one on the right for the up facing pump mentions the lever is incorrect in the engine fitting description details as this place is often a good source for added info in these situations in the marine world when they have them for sale,

^ plus it seems you'll want to know if your pump is set up for the vent or not.

The next following is of the down pump details if desired to know a bit more too on comparisons wise,

Let us know what you come up with and if it all worked out in your favor... Good luck.
 
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