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Rebuilding Force 125 questions

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altitude 411

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Hello Forum, My name is Keith and I'm rebuilding my 125 Force. I have a few questions that I could use help with.

Model # is 1251E9B. Is this a 1990 model number or 1989 model or are they the same? I don't find my model # when entering for parts #'s.
I have my power head completely torn down. Two pistons ate the rings. I am replacing piston's with weisco. Everything else looks to be in good shape. Bearings, rods, cam all look good. Can't determine why it chewed the rings in cyl #2 & #4? Common?
I'm looking at gasket kits and having trouble locating the "spaghetti" seal for the case. Any ideas where I can locate? Also need advice on what other sealants are needed. RTV brand recommendations? Loctite #'s, assembly grease ect?
I've built auto engines but this is my 1st marine motor.

I read on the net to chamfer the ports in the cylinder to prevent motor from eating rings. Is this true? I know there is nothing not true on the web but I wanted to ask anyway.:DThanks for any help or advise.
 
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89 the 125 wasn't made in 1990.
They introduced the 120 in 90
Actually the same motor, they just changed the way they rated HP.
The 120 is rated at the prop the 125 at the motor(I think? it might be the other way)
Get a factory manual, the others don't have the right info.

Yes a light deburing can help the rings just don't go too deep.
Any kit should have the spaghetti seal (F9698122)
If not you can probably get the part here on Marine Engine. com
Or e-bay has them(6$)

Get the best RTV and use black(looks better)
378642 OMC bearing grease. Don't use marine or automotive grease.
It's too thick and won't wash away fast enough and can cause the bearings to burn.
https://www.ebay.com/itm/0378642-OM...KxSHOds:sc:USPSFirstClass!32958!US!-1&vxp=mtr
 
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I am using 020 oversize pistons in my rebuild. Is it recommended to increase the fuel jet size? I live at 4600'. What size do you recommend? .088 or .090? other

Also, when ordering parts from this host it asks for hp, serial number. My serial number 1251E9B is not listed. Does anyone know what serial number is equivalent to mine on the listed numbers on this forum? Is 1251A9B or 1251X9B suitable?
 
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Another question if I may... I want to add a tach to help with run-in. I have read both 12 pole and 20 pole for a 125 Force. Can anyone confirm which is correct for me? Model 1251E9B. This is mounted to a 1990 Bayliner Capri which I believe is OE to the boat. Tried to upload pic of my stator but having trouble. It has 20 poles so I assume that is my answer?
 
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