sueybass

I was having problems with my zen not having any power. I took it apart and noticed the cylinder wall was scratched up. I ordered a new jug, piston, and cir clips. Put it all back together and took it out today, and now somthing wrong in the lower end. Motor made a funny noise and died. Felt like bearings went out. Took it apart, cylinder wall not scarred and piston still good. Turned the crank by hand without jug and it had a spot that seemed to drag. Kind of flopped over. Is that the magnetic shield in the flywheel? When I took off the coil, it doesn't do it. Seems to turn freely. I did notice a groove in the flywheel where the coil appears to have drug on it.

My crank turns freely, no grind or funny feeling.If the bearings were out would I be able to feel it? I'm thinking my coil was what made funny noise and stopped motor. Coil wasn't loose, so don't think it fell. But a definate fresh spot on flywheel. Could crank be bent? Bearings be out?

Bbbutch

I'm sure others will jump in shortly with specs on clearance between the flywheel and pickup coil. And yes it should not rub.
Grab the crank shaft on either end of the motor and try to move it up and down (not in & out). Any play up & down would indicate bad bearings along with any roughness while turning the crankshaft.
What mixture is your gas to oil?

sueybass

Definate movement up and down. Not much, but it's there. Running 3 oz/ half gal Amsoil. When pulling flywheel, how do you keep from getting out of time? Not a big motor buff, but really want to learn. As much as I have in this motor now, could've bought a new one. But no learning being a remove and replace specialist. Any pointers on changing bearings would be GREATLY appreciated.


Thanks!!

John

glennb2006

Changing bearings is pretty easy.

Get some spares in: New bearings, seals, gasket set. Remove flywheel, split case and remove crank. Remove bearings and seals from crankcases and fit new, reassemble. assemble cylinder and piston onto it all.

Cleanliness being next to godliness during all these operations - while it is stripped down do you not fancy doing some mild porting works to the cylinder?


Glenn


Glenn

sueybass

I would love to do some porting. Where could I get some detailed instructions? Or could you fill me in, Glenn? Does this effect timing in any way?

glennb2006

I have a good link to a web site, but not allowed to post links here, why not send me a pm with an email address and I will send you the link - or do a search on Jeroene tune .

There are a couple of pages worth looking at - some good tuners your side of the water too, but it is fun tuning your own motor - and easy enough once you get going.

Glenn

PEERPSI

Sounds to me like the real issue was your flywheel rubbing, new bearings may not be necessary. The flat spot as you called is the counter EMF effect of the coil as the magnetic field passes through it. Sort out the flywheel rubbing and enjoy. As for timing I expect it's keyed.

sueybass

I took the case apart. Going to get new bearings tomorrow. Just putting the crank in half of the case there was major slop.

thanks John

Body Guard

Hey John,
The Geordie Lad is right, change the bearing is just what you need. Happy boating pal.

Hey Glenn,
Glad to meet you here. My name is Latiff
Which part of Newcastle are you from and where do you run your boats ?
I hope its Newcastle -upon -Tyne and not under-LYME.
Would love to hear rc boating development in the Northumberland.
Here's my Email if you don't mind sharing the said subject with me [email protected]

Kind Regards

Latiff

Dockman

Hey Sueybass I have a new case with bearings and seals already installed. I bought it from Gizmo and just got it in the mail last week but I'm sending it back. I ordered it before I realized my cylinder/piston was shot also so I ordered a new motor. If you think you my want it I won't send it back? I paid $32 for it, let me know if you are interested? I'll be sending it back Tuesday or Wednesday.

ps: You are about 50 miles from me.

Roger

martno1fan

The best how to guide for showing how to modify your engine is over on modelgasboats its very easy to follow with pics of the process.The how to was done by Scott Schneider.Look in the how to section .
Mart

sueybass

Roger, sent you pm and email. Please give me a call.

Thanks for the link on the how-to.

Dockman

Thanks for the hook up.