The Hodaka Club Forum

I just got a 1972 hodaka 125,the motor is stuck and there is no oil that i can tell in the crankcase,what oil should go in crankcase? any tips on getting motor un stuck thanks jerry

Welcome, you will find lots of answers here. I have never "unstuck" an engine, but from reading I would start by putting and penetrating lubricant in the spark plug hole and let it set over night, pb blaster, marvel mystery oil, I've read people using tranny oil.. Most people recommend a modern 70 or 80 wt gear oil such as Bel Ray. good luck

I have a Combat Wombat motor that was froze up from being kept outside and a year later I finally got the top end off. Take the head and intake off. See if you have a broken ring, scoring inside the cylinder or rust. It will give you an idea of what you are up against. I soak the piston with PB Blaster and apply heat on the outside cylinder walls with a MAPP gas torch. Oh, make sure you are in a well ventilated area due to the fumes too. I normally use my Black and Decker Benchmate to clamp the crank case in place, let it cool down, and carefully use a rubber mallet to loosen things up. Take care not to hit the fins hard enough to cause them to break off...don't ask me how I know. Go through the oil, heat, hit, and cool down cycles to get some results. Once I got the cylinder up off the crank case, I hammered some wooden shims in between the bottom of the cylinder and top of cases to help lift it up. Once the top end is off you can remove the case bolts and split the cases. Sometimes the crank is rusted so bad on the left side, you must apply heat to the case bearing area on the outside of the cases and remove the crank and bearing as one unit. Make sure you have a copy of the Wombat/Combat Wombat shop manual, it is a great help when doing this kind of repair. Richard

To some extent it depends on why it is "stuck." A really small amount of corrosion can cause the piston skirt to stick, in which case a penetrating lube should let you get it unstuck and apart. Since this is a new bike to you and you weren't there when it got stuck, you might also consider that it could be seized, in which case penetrating oil may not work. Take off the pipe and see if you can get a look inside the cylinder. If the piston is down, you can. If it is up, you can't but give it a try because you have to take it apart anyway.

If you can't get a view through the exhaust port, keep taking things off. Tank, carb, and head. If the cylinder is badly scored and stuck, it is probably seized, and it may take some force to get it apart. Use lube anyway, and if force is needed, a two by two section and a hammer on the top if the piston should get things moving. Start light and increase force. I would avoid hitting the cylinder fins. You can't hit them hard enough to do anything useful, and they do break readily if hit off angle especially. Heat is your friend if it is badly stuck, but I would start with the assumption that the crank will turn, and try driving the piston down.

I once freed a five horse Johnson outboard that I knew was just stuck from sitting in the garage for years. I put a squirt of ATF in the spark hole every now and then, and let it sit in between. It took a while, but it eventually let go, and returned to service without any repairs. Just lucky. ATF is highly penetrating but have patience if you use that or penetrating oil like Blaster.

Go slowly. It will turn out okay.

I have the same bike. Take a look what I found in the cylinder and exhaust.




acorns

It is worth it to at least take off the head and have a look before anything else.

-Forrest

I pull the head, pipe and carb and hit all the hole with penetrating oil. Add some heat, plus with the head off you can tell if its the piston stuck or the bearings.

I had a pressure washer once that I caused the motor to be "stuck". I ran it completely out of oil, I just took it for granted that I never had to do preventative maint. on it because I bought the thing brand new, when I did obviously. It seized when I was using it, a friend of mine suggested letting it cool, then putting marvel mystery oil in it, let it soak overnight, I did, then stuck the largest size punch down the spark plug hole and tapped it, pulled the string and it freed up, I could not believe it, that was a Briggs and Stratton though, not a 2 stroke Hodaka, since then though, I have used Marvel Mystery oil more for different things. Just my 2 cents.

I did use that pressure washer for another year though, til the pump went out.