1981 Merc 9.8 where does this tube go?

AEROCOOK

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I was fixing the kill switch wires on my 1981 9.8 Merc and I came upon this little tube. It looks like it's supposed to plug in somewhere but I don't know where.
Can anyone offer some insight?
 

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AEROCOOK

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I think I figured it out, it's the pulse line for the fuel pump, looks like it broke off with a piece of it still in the carb body. I'll have to pull the carb off to extract the piece that's still stuck in there. Good opportunity to clean the carb while I've got it off.
 

Scott Danforth

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It is the pulse line. The little hose nipple is just pressed into the carb. Use a dab of red loctite to secure it.
 

AEROCOOK

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It is the pulse line. The little hose nipple is just pressed into the carb. Use a dab of red loctite to secure it.
Can you tell me exactly where on the carb it plugs into? The spot I thought it went to turned out to be a blind plug and I cant seem to see a hole anywhere else. Maybe I need to remove the carb to get at it?
 

racerone

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???????-----No it is not the pulse line !!!!------This wee hose removes gas oil mixture from bottom of the engine and puts it back into the intake air stream.---There is no pulse line for the fuel pump, that is done directly through a hole in the carb mounting flange !!!!!
 

AEROCOOK

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???????-----No it is not the pulse line !!!!------This wee hose removes gas oil mixture from bottom of the engine and puts it back into the intake air stream.---There is no pulse line for the fuel pump, that is done directly through a hole in the carb mounting flange !!!!!
Can you tell me where it plugs into?
 

Scott Danforth

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You need to pull the carb. It's on the bottom of the flange on starboard side
 

Scott Danforth

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3/8" wrench, 7/16" wrench and 5 minutes and the carb is in your hand.
 

AEROCOOK

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Well the carb is off and I still cant find the hole. I have a good view of the carb mounting flange and there are no holes on it. I found another post with the same question on the same motor and it was suggested that the tube fed oil up to the top crank bearing. This would make sense except that it isn't long enough to reach the top of the motor. If anyone who has one of these motors and could take a look and give me a clue, I would be very grateful.
 
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Scott Danforth

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I can take a pic tonight if I remember.
 

AEROCOOK

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I was able to find a picture on eBay (albeit a 1979 model) and the hose on that one went exactly where you described.
When I get home tonight I'm going to take another look just to make sure I'm not losing my mind ;-)
 

MTboatguy

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You have already lost your mind, you bought a boat and a boat motor!

:D
 

AEROCOOK

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You have already lost your mind, you bought a boat and a boat motor!

:D
LOL... More than you know, I have 7 of them and a few more in pieces...Only 1 Merc though.
On a more serious note, I have confirmed that the oil bleed hose does not go to the typical location on the bottom of the carb mount flange. I'm really stumped by this, The hose is only 4" long and I've spent a long time looking for the hole within it's reach.
The thought even crossed my mind that my motor somehow missed a stage in the machining process and never had a hole but
if this were the case, I'd expect to see oil residue in the lower pan and it's clean. I'm hoping someone can solve this little mystery.
 
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Scott Danforth

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Follow the blue hose ( I replaced the line about a month ago)

 

AEROCOOK

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Thanks for taking the time to provide the photo Scott.
It looks like the hose on yours goes into the carb it's self, right at the flange, it this correct? My carb doesn't have a hole in this location so perhaps it's not the original carb?
 
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AEROCOOK

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No Title

Here are a few pics of my carb.
 

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Scott Danforth

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Where does the hole in the middle of the mounting flange on the bottom go?
 
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