What is a Carburator type in Mecruiser MCM 3.0L engine?

dlogvine

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The engine is Mercruiser model MCM 3.0L serial number 0C860967, boat has an original engine and it is 1990 Bayliner 2050 . I tried to find a carburator's model and serial number but it has nothing on it. So I guess it is mercarb but I still need to find out what carb repair kit should I buy.
Thank you.
 

dlogvine

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I found a few carb rebuild kits online and the price range is from $18 to $150. Any advice as to how should I chose a good kit?
 

dlogvine

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older mercarb carburator rebuild kits.

My engine is Mercruiser model MCM 3.0L serial number 0C860967.Looks like it is a mercarb 2BBL carburetor, older model, it is original carb on 1990 Bayliner 2050.
I found a few carb rebuild kits online and the price range is from $18 to $150. Any advice as to how should I chose a good kit?
I found one for $35
http://www.ebay.com/itm/CARBURETOR-...EL-/181791878447?hash=item2a53a3ed2f&vxp=mtr#
 
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Fishermark

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I see you started another post with this question. It is best to keep it all in one post, that way people can answer one thing and it keeps confusion down. ;)

Having said that - the basic rebuild of a carb includes the gaskets and needle valve parts - very little else. Rebuilding a carb is more about cleaning passages and putting it back together. You do not need to spend much money on a kit.
 

stonyloam

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I am not sure you have an "older" Mercarb per say. There are (as far as I know) only two Mercarb kits. The main difference being the accelerator pump plunger. Look at that photo. See the accelerator pump plunger with the 90 degree bend on the shaft? That is the " new" style carb. The "old" style has a acellorator pump plunger with straight shaft. So check your carb, and if the plunger has a Bend, that is the kit you need.
 

dlogvine

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Thank you guys, I did take apart, cleaned and reassembled the carb with the new parts from the kit. Just a couple questions, that I came up with while rebuilding the carb, btw it was a newer version with a bend accelerator pump. First question: when I tried to unscrew the fuel line, it had a double nut, one was on the pipe itself, the other, I believe the locker was in the carburetor. I was not able to unscrew the fuel line since the nut sitting on the fuel line was not moving at all. Seems like a fuel line is slightly deformed, and that prevented the nut from turning. I hat to unscrew the fuel line from the fuel pump and then after carb removal, I unscrewed the locker nut and then separated it from the tightening nut on the fuel line. And I'm planning on just reversing the order in complete carb assembly, so I'll screw the fuel line to the carb and then attach it to the engine and the fuel pump. The question is does it matter if I do assembly this way or should I try to make the tightening nut on the fuel line to move? I'm afraid if I try to do this, I'd break the fuel line.
Second question, I was not able to loosen the screw holding the lever in the choke housing. I was afraid to rip the screw and it was sitting too tight. So I did not change the gasket between the air horn and the choke housing. The gasket looked ok, so I assumed it won't be too important. Or am I wrong?
 

Fun Times

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To help aid in the removal of the smaller fuel line nut from the bigger connector nut screwed in to the carb, you'll need to use two wrenches.

In order to avoid any/further rounding out of the smaller line nut, you'll need to only use a 5/8 inch flare nut line wrench...Anything else will strip/round out the nut especially if it's tight....Same should go for the line nut at the fuel pump. While turning the 5/8 flare nut line wrench, hold the bigger nut in place with either the required 1 inch or 1 1/16 inch wrench size?.

http://www.bing.com/images/search?q=flare+nut+line+wrench&FORM=HDRSC2

Also gently using an impact screwdriver set along with PB blaster penetrating oil should help get any difficult screws to loosen up.
http://www.bing.com/search?q=impact...nversationid=5228068E54D540F99F03673175BB4181

http://www.bing.com/images/search?q=PB+Blaster+vs+WD-40&FORM=RESTAB

Good luck.:)

$_57.JPG
 
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