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larrywcc

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"Hi,

Does anyone know how t

"Hi,

Does anyone know how to tell the difference between a 2.5 and a 3.0 I recieved a boat that was free but don't know much about it other then it is a 120 hp with a straight 4. I was told there was two of these as a 2.5 and 3.0 There are not many markings on the motor unless there are cast into the back. I have found nothing much with these numbers.

Who ever owned the boat, had water get into the carb then into the engine that has been sitting for sometime.

The motor does turn, so I taken the motor apart and now I go though and taken off all the numbers on the pistons etc... but no reference numbers match anything and if I try to search for omc 120 hp almost all sites don't have anything in stock and this site has the most links and seem to show in the inventory that there are some items I could use. I tried the Feedback system here and havn't recieved any reply yet. So anyone know how or were I can look to cross reference my parts for replacment parts ?

Also, what type of oil goes in this plus oils that go in the outboard/stern ?


Thanks for any help"
 
"The 2.5l has Only a Pulley on

"The 2.5l has Only a Pulley on the front of the crankshaft,......
The 3.0l has a Harmonic Balancer as well as the Pulley.......
And,.....
At 120hp,...... You've got the 2.5l...."
 
"OK, mine has a pully and behi

"OK, mine has a pully and behind that I taken off and there is another part that I tried to take off I assume you call the the Harmonic Balancer ?
Was tring to get that off to check the chain. But I didn't want to put to much pressure on it as I don't want to break it as parts are hard to find.

So then I can assume this is really a 3.0 ?

I believe the the boat is around the 70's

Thanks for your HELP !

Larry"
 
"[b]"Was tring to get that

""Was tring to get that off to check the chain. But I didn't want to put to much pressure on it as I don't want to break it as parts are hard to find"

If it's about 6"/ 8" in Diameter,......
You've got a 3.0l,+ you need a Puller to remove it........

If it's 3"/ 4" in Diameter,......
It's the Crankshaft Hub,+ you've got a 2.5l.....
And,.....
You'll Still need a Puller to remove it......"
 
"Oh, thanks. Then I do have t

"Oh, thanks. Then I do have the 2.5L

What type of oil goes in the motor ? Anything special ?

Plus also, the outboard. I found a manual on ebay that I will get in a week or so. But from what I understand there are two places for the oil.

What type of oil goes in these ? I would like to drain out the oil and replace with new so I know all of it is new.

Thanks again for your HELP !!!!!!!!!!!!"
 
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