Mercruiser 3.0 choke missing

[nemyarbretlaw]

Hi, I have an 89 Mercruiser 3.0. I just bought the boat and the previous owner claims the previous owner before him had just put in a carb kit. Well I believe that because I found an unused gasket under the seat. My first notice is that the choke butterfly is missing. The screws are in the shaft but have no heads, just knurled bottoms. The choke housing is empty and it appears there is a wire in the loom by the carburetor that is snipped closely enough to indicate someone just did not want the choke any longer. The engine was difficult to start but once warmed up runs great. The tag has been left off after the rebuild but I am certain it is a Mercarb. My big question is this: Is there any type of primer type system that someone could have put on this? It appears it has been done intentionally. If I think so, I will just buy a new or rebuilt complete unit and swap it out. Were these electric or manual choke? My engine serial number is OC530705. I have ordered manuals but they are not here yet. What do you think. Thanks.

 

[ErieRon]

Re: Mercruiser 3.0 choke missing

There were two carbs used as far as I know. A Mercarb and a Rochester 2GC. The Mercarb only has one needle valve, while the Rochester has two. The serial number is stamped on the rear face of the carburetor, as well as a date code. Not sure about Mercarb, but Rochester will start with a 170, or 70. Does the chocke have an electrical connector on the housing? If so, how many wires and what color?

Edit: Double check your engine serial number too. All of the factory service manuals are here and can be downloaded free...thanks to some great members. I looked and your serial number didn't look quite right for an '89 3.0...but I could always be missing sometihng too...

If you go to the "Adults only" section at the top of the page you can view the manuals available for download. Far better than the after market versions.

 

[nemyarbretlaw]

Re: Mercruiser 3.0 choke missing

It only has the one needle valve that is why I thought it was a Mercarb. As far as the choke, there is no connectors on the housing. Just the back half of the round housing. I have not tested the one wire that is snipped off. I believe it is green. Thanks

 

[ErieRon]

Re: Mercruiser 3.0 choke missing

Yep, one needle valve is a Mercarb. It had an electric choke as far as I know. It seems you're missing the cover. That's where the electrical connector was. The green wire is a ground and typically just ran to a mounting screw on the O.D. of the housing. If you look around aft of the choke, you'll probably find a loose plug with a black and purple wire in it. Some had a pink resistor wire, but I don't think yours did.

I'd just put a rebuilt carb an it and call it a day... I think the choke assembly alone is around $110.00 now.

I would think if it had a primer system of sorts, it would be pretty easy to spot.