zdz60 front bearing leak
 

im not having much luck with my ZDZ60. on a gallon my ignition just died took $200 to fix that, now my front bearing leaks and offcourse tuning went south. the leaking bearing leans the mixture, any advice on what bearing to buy with a better seal?

RE: zdz60 front bearing leak
 

A fellow flyer here had the same issue on his ZDZ 80 Contacted the ZDZ factory, sent it to them direct, (we live in Canada), and they had to put new cases on it, all done under Warranty. You can try this sight, http://zdz-modelmotor.cz/zdz/en/ e mail them. Thats if your motor is still under warranty.

Just recently my ZDZ 80 had the lead counterweight plugs on the crank come loose and start rubbing on the bearings. Sent it to them direct too, they are great to deal with, sorry about your woe's.

RE: zdz60 front bearing leak
 

The reason for which you have this problem is that you run too lean. The solution is to enrich the high mixture.
Yves,javascript:void(AddText('[8D]'))

RE: zdz60 front bearing leak
 

That's a new one :eek:

RE: zdz60 front bearing leak
 

I doubt it! Mine started leaking at abot 2 years old and it was not run lean.
Sent it in and they replaced the bearing,cylinder and piston and sent it back no charge.
I still dont know why or what happened and when I enquired didnt gain much info.
Good service from RC Showcase tho.

RE: zdz60 front bearing leak
 

The front bearing can get loose in the case. The factory uses loctite bearing mount and an interference fit to hold the bearing. If the interference fit isn't very tight, then the bearing can get loose as the case heats up because aluminum expands more than the steel bearing. A bigger bearing boss would help to hold the bearing tighter, as would a clamping bolt around the front bearing (like 3W uses on their 106). Keeping the engine cooler will also help, bigger fins and better airflow to shed heat.

If someone tells you the front bearing got loose because the engine overheated, ask them why the rear bearing didn't get loose. The hottest part of the engine is the cylinder and heat conducts from hot to cold, so the rear bearing has to be hotter than the front bearing because it's closest to the source of heat. The answer is that the rear bearing has a bigger bearing boss to grip the bearing tighter than the front bearing.