Force 70 HP 1991 Serial # 0E10792?

Royalwapiti

Cadet
Joined
Jun 26, 2015
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19
I bought a boat last summer with this motor on it. Would like to tune it since I do not know when it wa last done and it doesn't always want to idle when trolling. Is there a certain kind of spark plug that runs better in the Merc Force motors? It seems odd but I have run into cars that will run ok with one brand but they run better with another brand of plug, like NGK. Chevy trailblazers run noticably better with AC-Delco plugs. Does this phenomenon exist in Force boat motors? Otherwise I will likely buy the NGK buhw. It currently has Champion L76V.

And how come most places asking for a serial number come back with nothing for my serial number? Too old?

Thanks
 
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Jiggz

Captain
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Oct 23, 2009
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The serial number needs to have 6 digits after the Zero and "E". So in your case it could be a "0E010792" or "0E100792", etc. However, most boat parts store only needs the model number to get the correct parts.

As for your idling problem, you sure can use NGK's BUHW if you so wish. Personally, I find them to run my 125HP idle smoother. Additionally, make sure the idle screw (bottom of the timing tower) is set properly. Technically, it should be set so the idle in gear rpm when in water is around 750~800 RPM. Depending on your prop size and type, the idle in neutral could be as high as 1000~1300 RPM.

Finally, the idle mixture screw should be set around 1~ 1 1/4 turn out from lightly seated.
 

Royalwapiti

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Jun 26, 2015
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Yea, I left the last digit off on purpose, regardless, iboats and another site didn't recognize the e10792X or 0e10792x or OE10792X. I don't know the model number, my motor has a sticker with serial number only.

I'll try the adjustments for idle. Thanks
 

jerryjerry05

Supreme Mariner
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May 7, 2008
Messages
17,923
The tune up on most outboards is new plugs and check the air screws and check the timing..
​Sometimes they magically get turned in by themselves??
Change the impeller and the gear oil.
Just don't remove the wrong drain plug.
 

Jiggz

Captain
Joined
Oct 23, 2009
Messages
3,817
Yea, I left the last digit off on purpose, regardless, iboats and another site didn't recognize the e10792X or 0e10792x or OE10792X. I don't know the model number, my motor has a sticker with serial number only.

I'll try the adjustments for idle. Thanks


If you go on boatsdotnet you might be able to identify your motor model number by comparing major parts like the ignition system and the fuel system/carburetors, etc.
 

Royalwapiti

Cadet
Joined
Jun 26, 2015
Messages
19
That one doesn't work either. I selected Find Parts, then selected Force, then enter 107924 nothing found then I entered E107924, nothing found

Oh Well.
 

Jiggz

Captain
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Oct 23, 2009
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3,817
Like I said, you will have to use the diagrams and refer to what is the best identical to what you have to find out the model number. If that is too hard then you will just have to wait until someone who has an identical motor with the same serial number as yours will chime in! And you know that time will never come as serial numbers are unique to only one motor.
 

jerryjerry05

Supreme Mariner
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May 7, 2008
Messages
17,923
boatsdotnet, Mercury tab, force outboard from the top group,then find 70hp and open the link.
​The serial# for your motor runs OE000001-OE138599
The changes from year to year seem to be NONE!!
So any parts you need can be ordered from any of the 91-95 70hp.

What are you looking for?
 
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