Mercury Comet KF 3 impeller questions

[freddyray21]

Got a question for the knowledgeable. According to the plate on a motor I just picked up last night it is a Mercury Comet KF-3 3.6 hp with a serial number of 359749. But according to http://www.oldmercs.com/models.html A KF-3 is a 3.5 horse and that serial number doesn't match. I just want to know so I can get the right parts. The motor has 130lbs compression dry. Of course it has no spark, but it seems none of these motors I pick up do. I think it will be a good little runner.

 

[tmcalavy]

Re: Mercury Comet KF 3

Re: Mercury Comet KF 3

A KF-3 is a 49 Comet rated at 3.5 hp, so there may not be an official serial number record to compare it to. Pull the flywheel, clean the points, inspect the coils, wires, condensors and connections. I bet you get spark back unless the coils are toast and they may be. If they're cracked, delaminated you'll have to replace them. Also check the LU grease level, Lubriplate 105, and be prepared to shut it down on the first run in the barrel/tub if the water pump/impeller aren't working. Good little motors...I'm fond of the even earlier 1 cyl. Merc's and Wizards with the Buck Rogers look.

 

[freddyray21]

Re: Mercury Comet KF 3

Re: Mercury Comet KF 3

that's what I got too, but the plate clearly states 3.6 hp. I figure to pull the flywheel maybe tomorrow to see.

 

[diaric]

Re: Mercury Comet KF 3

Re: Mercury Comet KF 3

found another site that lists the previous year, at 3.6 ke-5 comet deluxe. so there coulda been some parts cross over
http://www.infoblvd.net/sah/40-59_merc_model.html

 

[Scaaty]

Re: Mercury Comet KF 3

Re: Mercury Comet KF 3

Take it to the masters...post in "ask a member"...you will be SWAMPED with info

http://www.aomci.org/aomc.htm

 

[freddyray21]

Re: Mercury Comet KF 3

Re: Mercury Comet KF 3

pulled the flwheel and cleaned the points and I have spark. Does anyone know what the gap is. I am assuming .020? It started on the first pull though it will need a carb float and impeller. I have them on order. Also it seems as if there is a lower cowling missing and the front of the carb has two screw holes. I am guessing the choke would be there.

 

[diaric]

Re: Mercury Comet KF 3

Re: Mercury Comet KF 3

champion j7j @ .025

 

[freddyray21]

Re: Mercury Comet KF 3

Re: Mercury Comet KF 3

Actually I was asking about the points. The plug is a Champion J8C though

 

[diaric]

Re: Mercury Comet KF 3

Re: Mercury Comet KF 3

points, .018. manual says j7j for plugs but i see a champion site lists j8c for all old ones to 1959.

 

[diaric]

Re: Mercury Comet KF 3

Re: Mercury Comet KF 3

update, they don't stock the j7j anymore and have the j8c as replacement

 

[freddyray21]

Re: Mercury Comet KF 3

Re: Mercury Comet KF 3

thanks. I have ordered an impellar for it, but am curious as the shaft does not have the tell tale round spot in it for the impeller. I am assuming it is in the lower unit at the top. I don't have a manual so would appreciate any instructions on how to do this one. I have done several in the past but all Evinrudes or Mercruisers.

 

[diaric]

Re: Mercury Comet KF 3

Re: Mercury Comet KF 3

some of the old ones are behind the props. this shows schematic of yours
http://www.crowleymarine.com/mercury_parts/1713/160.cfm

 

[freddyray21]

Re: Mercury Comet KF 3

Re: Mercury Comet KF 3

looks interesting. I think I will need a manual for it. I found one but they want 50 bucks for it.

 

[diaric]

Re: Mercury Comet KF 3

Re: Mercury Comet KF 3

its cheap investment, 1/2 hour of shop time . old stuff like that, few who have expierence to answer a lot of questions

 

[Laddies]

Re: Mercury Comet KF 3

Re: Mercury Comet KF 3

It's quite a simple job here a picture break down

 

[freddyray21]

Re: Mercury Comet KF 3

Re: Mercury Comet KF 3

thanks. That is most helpful.

 

[freddyray21]

Re: Mercury Comet KF 3 impeller questions

Okay so I took mine apart and it doesn't look like the picture above. I pull the pin off of the cone, unscrewed the cone. pulled the prop off and mine has the water pump cover that screws into the housing (left hand threads found out the hard way. jb weld in order) then the impellar. The thing is I cannot see how it gets water into the impeller. Unless it is through the little holes pictured. the little holes look like they fit a spanner wrench though.

 

[freddyray21]

Re: Mercury Comet KF 3 impeller questions

okay by squirting pb blaster in the hole I found out where the water goes. Doesn't seem like much passageway, but it's not blocked.

 

[Laddies]

Re: Mercury Comet KF 3 impeller questions

That picture looks like a quicky lower unit from the water pump cartridge. if it is and the left hand treads aiso sound like a quicky, you have a rare bird indeed the quicky were built for the KG4H and KG7H engines and not for that powerhead can you send a side view of the unit and another of the whole engine please

 

[freddyray21]

Re: Mercury Comet KF 3 impeller questions

http://www.fiberglassics.com/forms/forum818/showmessage.asp?fm=Forum&messageID=5386

Here are pics of the motor. It is hard to say what has been done to the motor over the years. I am only going off the serial number and information off the cowl to verify what the motor is. I do know it has good compression and after cleaning the points it started on the first pull. I have ordered parts, but now wonder if they are the right ones.