1964 3.5 hp McCulloch Wizard

[spirtS niggeB]

I recently picked a 1964 3.5 hp McCulloch made Wizard from my grandpa. MLM 6904B. Flywheel will not spin, took lower unit off. Gears are rusted but do not look too bad, they turn and whatnot. This leads me to believe the piston is seized? Still working at tearing it down with my spare time.

Any help with parts or advice would be awesome. thanks

 

[twocyclemania]

Re: 1964 3.5 hp McCulloch Wizard

I have a similar motor (62 Scotty 3.6 by McCulloch) that I picked up in the same condition; seized. The motor looked like it was new and was most likely seized from sitting. I poured the various liquid concoctions into it from both sides (spark plug hole and intake). You should try this first and let it soak for as long as you can. Most of the time this doesn't work for me. I than take the carb and intake off. This exposes the crankshaft counterweights. They're the toughest part that can take the most 'abuse.' I use a plastic/teflon or even wood pin on the counterweight and hit it with a hammer. Keep tapping it with a little force and don't be a caveman. This is how I've 'unstuck' a number of motors besides the Scotty. Others have their methods but this seems to work for me. I'm currently trying to unstick a 54 Evinrude 15 Fastwin that I'm letting soak. Once the piston starts to move in the slightest it's given up the seizure ghost and you should be good to go. Let us know how you make you. Good luck. ps Dont even give a minutes thought to trying to loosen it via the nut on top of the flywheel. You'll snap the crank.

 

[spirtS niggeB]

Re: 1964 3.5 hp McCulloch Wizard

Thanks alot for the response, it was a big help. I took the carb and intake off, poured 2 stroke oil and let sit for a day or two. Started tapping today and the counterweights began to move. I can pull the start string and it actually moves the prop a little bit now. I just poured more oil in and now letting sit longer.

thanks again 2cycle

 

[twocyclemania]

Re: 1964 3.5 hp McCulloch Wizard

Glad it worked out and you didn't have to tear the motor down. Once it starts to move you should be able to 'wiggle it' back and forth as it gives up more of the 'seizure ghost' and you should be good to go. Spin it and see if you have spark: Hopefully you do but if not you'll need to clean/dress the points. While you have the carb off it's a good time to clean it out. Before you try to drop the bowl make sure you back off the 'high speed' jet (the lower one) or you will bend it. Keep this in mind with any Tillotson carb. Let us know how you make out.

 

[twocyclemania]

Re: 1964 3.5 hp McCulloch Wizard

Forgot to mention: Check out the gas tank and make sure it's not a rust bucket. If it's not seriously rusted you may get by with a cleanout. You don't want to clog that carb you just cleaned. I've used in-line filters but they seem to restrict the flow (like to know what others think about them).

 

[spirtS niggeB]

Re: 1964 3.5 hp McCulloch Wizard

The gas tank is good and the carb is clean, there is only one. The motor turns nicely now, but i'm not sure how to check for spark. The plug needs to be replaced and it currently has a lawnmower plug which is corroded. Do you have any idea about what plug it takes?

 

[twocyclemania]

Re: 1964 3.5 hp McCulloch Wizard

Checking for spark is easy. Just have wife/girlfriend/kid (family method) hold the sparkplug (removed )while attached to the plug wire. Spin the flywheel. You'll know if you have spark by the immediate response. Only problem with this method is you won't get much more cooperation if you should ask them again. Other than that just have the plug tip (removed) grounded to the motor with the wire attached and give it a spin. You should have spark if your ignition system is up and running. You can pick up an in-line spark tester for a few bucks. It lights up as the motor 'sparks.' These are great. As for the the plug; the original has been superseded and I don't even know if the one I have in mine is the correct one so I don't want to tell you get the same plug. NAPA should be able to reference it or try some of the sites on-line. Another interesting site is Odd Job Motors for Scott and other makes; check it out. Keep us up to date.

 

[spirtS niggeB]

Re: 1964 3.5 hp McCulloch Wizard

Got a good shock from the plug so ignition is firing! Wondering what your plug is gapped at? Thanks for the site recommendation btw.

 

[twocyclemania]

Re: 1964 3.5 hp McCulloch Wizard

The intent was for 'someone' else to get the shock; part of the fun. Anway, there's a reply on this site about the plug being .035 and the plug being an H10 J or C. I have a H10 on mine so I must have looked it up once upon a time.