Crankshaft moves

David D.

David D.

New Member
Hi Norm, I am still kinda new to these little engines but this one seems to have a problem....it is a new engine (from flying horse) 66cc and when i took the cover off to grease the gears, the pinion gear was not aligned with the ring gear, was sticking out about an 1/8" so i pushed on it with my thumb and it moved back in place, it's not loose, the whole crankshaft moves...i took the cover off the mag to verifie this.... is this normal? will it cause me any problems down the road? how can i fix it? is there a thrust bearing or shims on the crankshaft? thanking you in advance,David
 
yea ... i could understand that with the cylinder off... piston would keep it centered when assembled.... this is the crankshaft... in a fully assembled engine....
 
yea it runs fine , no more vibration than my other engines... my concerne is that i may have a bearing spinning in the case, or the crank rubbing on the casting.... i hear noises in it , but i hear noise in all of them , as there is no way to set the gear lash, or properly lubricate them.... you there norm? little help with this one? really would be appreciated, thanking you in advance, David
 
From what I've seen on these engines. Some have what look like a ring of wire that is used to set side to side play on the crank. The ring is placed in the bearing hole of the crank case then the bearing is put in place. the wire ring causes the bearing to not set as deep in the hole. Where you get these rings? Beats me. You could use a very thin washer with an outside dia. the same as the bearing and the id. just enough to allow the bearing to shoulder against it.
How much side to side clearance is needed? I've yet to see a book or manual or blue prints for one of these engines. My best guess is no less than 0.003 or more than 0.008', or as long as nothing rubs that shouldn't.
I have one engine assembled from parts and it has a bunch of side to side clearance on the crank I even made a couple of shim washers, and made a thinner split case gasket to take up some of the slop. I've only test ran it so I don't know if it will live long, it runs fine the way it is.
 
hmmm i got an old flying horse engine hanging out i i too have this crank endplay....never thought much about it....i do want to rebuild this one...good idea with the thinner gasket norm....well let me measure my end play and if someone has an new gasket to measure up i can figure out what size gasket paper to make the new one...thank you david d good topic
 
I just replaced the crank in my engine. The new crank is a bit slimmer and is one piece instead of the stock 3 piece.

I notice there is now a couple millimeters of play in the connecting rod assembly side to side. I'm going to try to narrow it down to max a millimeter. If not, I'll let you all know how it goes.

David did yours run fine?
 
The cranks usually have shims on them already but after awhile they get pretty beat up and distort . I set mine up with about 8 to 10 thousands end play . Your going to have to search for shims if you need some . The last motor I did I just bought some flat shim stock and punched some out . You can get it in different thicknesses its going to require you take the motor apart a couple of times to get it right .
 
I'm going to head over to lowes today and try to find a decent washer that I can grind to the proper diameter. I'll let you know what I find. I'm currently looking at "Fender washers" their used for autobody stuff. The tough part will be drilling out the center.
 
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