Carb for 1985 Mercury 25XD

[paxmule]

Hi all, Got the motor mentioned in the subject line for a great price. It has no carb and I am of course having trouble finding one. It has compression and spark. It also looks like it has provisions for an electric start but doesn't have one installed, as it has the button on the throttle handle and a couple wires with snow caps rolled up and neatly ziptied as if it came from the factory like that. Not really worried about getting the electric start going as much as i am about finding the carb. Carb should be a carb/fuel pump/prime/manual choke all one assembly. Engine SN is A173624. Anyone have one used or know of a lead or an alternate? This is a little winter project trying to upgrade from my force 15.

 

[Scott Danforth]

if you are looking for a used carb, go to sites like AOMCI.org or ebay.

if you are looking for a new carb, look at any of the parts breakdown mercury selling sites and buy one.

 

[paxmule]

NLA at all websites selling new parts. None currently for sale on ebay or antique motor site classifieds.

 

[racerone]

Your location ?

 

[paxmule]

Southern Maryland

 

[racerone]

Might be too far away , and a border for me to help on this one.

 

[Scott Danforth]

NLA at all websites selling new parts. None currently for sale on ebay or antique motor site classifieds.

its almost 40 years old.

 

[paxmule]

True, But i figure there is at least one good one somewhere out there in the world and im doing what i can to try to find it. If i never do, well i paid peanuts for the motor.

 

[paxmule]

So, I AM seeing some electric choke versions of this carb here and there with part numbers that show up in the parts diagram that fit this motor. Is it possible to convert this to electric choke on a motor that was originally manual?

 

[racerone]

Yes there are ways to use the electric choke carburetor on a manual start motor..----Just need to use a manual primer as found on many Johnson / Evinrude motors.

 

[paxmule]

Not sure how I could get a manual prime. That's part of the manual choke on the other type of carb I was looking for. Here's pics of what I've got

 

[flyingscott]

Do you know anybody in WI? Pretty sure I have one. You are also missing the whole choke assembly.

 

[paxmule]

Yes I'm also missing the choke/primer bracket assy with its primer arm and fast idle lever. The closest person to WI that I know lives in manistique MI on the U.P. But if you do have one with all that attached I would be willing to pay shipping to MD.

 

[Scott Danforth]

Guys, take it to a private chat please

 

[racerone]

Did this motor catch on fire ?

 

[paxmule]

No. It is just dirty and old. Like I said it is a winter project. I will have it looking great before long.

 

[paxmule]

I have acquired a WMC-32 carb from a 1989 25HP marathon. The body is the same and the gasket that came on it is the same as the one that was one the engine. The primer mechanism assembly is slightly different but i think i can make it work with a little modification to the lower cowl. Its the type with a round knob instead of a square knob. The original 1985 carb primer bracket would be a 41717T but the later carb i have is a 12803. The WMC-32 has an electric choke. I'm trying to figure out how to hook it up. I'm thinking that the way the electric choke works, is when it gets a 12V signal, the little rubber plunger closes a tiny orifice on the upper part of the carb. I applied 12 volts to it and the little plunger did shut against that little hole. But how does it know when to open again? is the spring mechanism on the other side some kind of thermostatic valve that opens back up when its warm? If so, i can hook up a toggle switch to drive it since i have a manual start.

 

[flyingscott]

The way that Choke works is you pushing the key and it closes the little port. When you release the key it uncovers the port. Your primer mech would have had the square know. The newer style has a round knob.

 

[paxmule]

Ok for the choke, that's easy, I can wire a toggle switch to my fish finder battery, flip the switch, pull the rope, then flip the switch back off. For the prime mech, I had nothing to begin with. Bought the engine with no carb. The WMC-32 I bought has the round knob style so I'm going to have to modify my 25XD lower cowl a bit to make it work so that the block for the knob has something to attach to.

 

[paxmule]

Here's what I mean. The lower cowl for the 25xd that would use the square primer handle doesn't work right with the block for the round handle. Unless I can somehow find the 41717t bracket that fits the square type, I'll have to rivet a piece of aluminum over this square hole and cut it to fit the round handle block. Also, im not sure if the idle wire for the newer style fast idle lever is shorter or longer, but i hooked up the one that was on the motor already and when i turn the throttle, it wants to pop out of the groove on the lever.