Mariner 40E 6E9 S 103761 Can't find a definitive year or manual

CharleyMarbles

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Trying to figure out why it dies under load. I've cleaned and rebuilt the carbs new fuel line checked compression it's good. good spark I can wind her right to redline unloaded in natural?
 

Scott Danforth

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Doesn't take much of any amount of fuel to run high RPM in neutral

You most likely have a fuel delivery issue

What are tbe compression numbers?
Can the spark jump a 1/2" gap?
Did you do a link and sync?
 

Mohawkmtrs

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As per Brunswick Marine:
Mariner Japan Sourced 1974-1992:
6E9 102889 1984
6E9 103919 1985

Your Mariner (6E9 S 103761) is a 1984 model.
 

Fun Times

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Merc service manual part number 90-84520-2 / 190
Covers 40A (676-A)/40B (676-B) 40C (6E9)/W40 (676-A) (I) All Serial Numbers.
 

CharleyMarbles

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Thank You all for your replies and here we are still in conflict over the year ?!?!?!?! Funny thing is most of the parts sites don't show a 1984 model year they skip from 83 to 85. very frustrating ? ? ? ?
 

Fun Times

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While i don’t believe there’s any real difference between the two years plus the variance of years suggested is sort of a long history story, I’m able to find that your serial number transpires over to model number 7040505
7040505 in which suggests the year to be 1985.
1985 40 [E]
Parts Group: 40H.P.
Options:
Electric start, short shaft (15”/381mm) driveshaft housing. Remote control steering
Model style: E

But yes, the Marine Engine Look-Up serial number range guide suggests it’s an 1984.
40C E6E9-102889 - 6E9-1039181984
40C E6E9-103919 - 6E9-1047981985
 

muc

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40E 6E9 S 103761​

doesn't seem to be a valid model type letter per the Merc bookIMG_20260829_133044343_AE.jpgIMG_20260829_133106970_AE.jpgIMG_20260829_133113157_AE.jpg

 
Last edited:

muc

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Service manual is the same for all years. p/n 845202 is the newest -- it's on back order till next month YMMVIMG_20260829_141628469_AE.jpg
Parts list can be 1of3 depending on year and Model Type
 

Fun Times

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muc

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MercNet had a refresh a few years back and lost a lot of stuff, some of it was support for older product. I couldn't find anything on MercNet for this engine.
Without the Model Type, I'm guessing O.P. won't be able to find the year. As *7 shows, Merc didn't track model years on these engines.
If O.P. wants to look up parts.
Mercurymarine.com
Parts and Maintenance --- Parts Catalog
Outboard
2 Stroke Carb
40C (twin carb) (auto-blend)
6E9-105014 to 6E9-150000
is my best guess

I looked up head gasket ---- still available!
Then I looked up carb kit --- $309 Picture shows enough to do 2 carbs. p/n 17068M PNLA so once they sell the 8 they have -- no more.
 

Fun Times

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That’s a bummer they lost a lot of past info such as that… shocking honestly.😔
Thankfully using the Merc online launch parts search function (and a few others out there) still offers model numbers and parts catalog guides for this engine serial number in particular but has been both found to be right and wrong engines that come up according to other sources for these cross breed engines of that era so caution is needed where possible.
Component


Catalog


Model Number


15 HPARCHIVE CAT 8018697015207AW
30A[689-000366 THRU 022058] - Belgium - Cat.# 90-849527030500
30A[689-100251 THRU 105324] - USA - Cat.# 90-849527030500
30A[689-301911 THRU 321376] - Belgium - Cat.# 90-849527030500
30A[689-401216 THRU 411946] - Belgium - Cat.# 90-849527030500
40C (TWIN CARB)[6E9-000106 THRU 6E9-007665 (M)] - Belgium - Cat.# 90-976687040505
40C (TWIN CARB)[6E9-100101 THRU 6E9-105013 (E)] - Canada - Cat.# 90-976687040505
40C (TWIN CARB)[6E9-300126 THRU 6E9-309343 (ML)] - USA - Cat.# 90-976687040505
40C (TWIN CARB)[6E9-400231 THRU 6E9-423162 (EL)] - USA - Cat.# 90-976687040505
1 – 9 of

 

boscoe99

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Seems that for the most part Mercury Marine no longer offers spare parts for those motors made by Yamaha but sold by Mercury. In many cases they can be obtained from a Yamaha fealer.
 

CharleyMarbles

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Ok so here's where I'm at on this thing we have cleaned the carbs new fuel line new fuel pump good plugs and compression. She still falls on her face under load. unloaded she will wind up to the moon. Any Ideas where I should go from here? Is it possible the jets have been damaged? Did notice it seamed to do better if I set the choke to about half. Anyone know a good OB mech. in the Flint Mi. area?
 

boscoe99

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Sounds like the carburetors are not doing their job.

Were the carburetors completely dismantled and cleaned in a heated ultrasonic cleaner? If not that is where I would start.

When the motor starts to fall on its face have someone spritz some gasoline into the air intake. If it picks up and runs then that is a pretty good sign there is a carburetor problem.

Revving a motor with no load proves nothing. And you risk damaging the motor.
 
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