Outdoor Power Equipment (Lawn Mowers, Snow Blowers, Chain Saws and more) Discussions

I picked up a nice clean 3000 watt generator from CL with a small crack in the bottom of the crankcase that allows the oil to drain out slowly (fell off the back of a pickup). Any one have any suggestions/experience for repairs other than welding? I'm hoping maybe Devcon, JB weld or some metal epoxy?
The motor is a clone, Lifan 168F2 196 cc and parts seem to be quite rare. The manufacturer will ship a replacement crankcase for $62.00 + transport, which is probably close to what I would pay to have it welded.
Thanks

   I've done over four rod caused block cracks with J. B. Weld.   I forget the temp rating but it was enough.  The cracks were all in non-load bearing areas.   Engines with cracks across a structural member or where the crack edges don't line up because one side if puffed out a bit get scrapped. 
 
  Depending on the crack you can do:
  Drill stop the ends of the crack.
  Widen the crack to allow working in the glue.
  Make a slight V on either side for holding.
  Rough the area.
 
 
   Not to quibble but what is the Lifan a clone of?   Sometimes it seems any Chinese made engine is dubbed a "clone".   A GX200 is 196cc and Lifan makes a clone of that (66014, 66015 and others) which are part for part interchangeable with the GX200.  Lifan also makes a zillion other engines.

i used jb weld to repair the casting where the drain plug is threaded into the bottom of a portable generator motor.the machined hole was not perfectly centered in the casting and one side was thinner than the other.wrapped some teflon tape on the plug threads and must of threaded it in too far and cracked one side of the threaded bore.drained the motor of gas and oil so i could tip the engine upside down to repair the casting.i was lucky because the crack was centered in a cast well with four sides that i was able to clean,degrease,and fill completely to the top with jb weld.i would try the jb first.

I'm more of a buster than I am a fixer, but doesn't the expansion and contraction of the aluminum create problems with the JB Weld repair?

I guess my question has already been answered since you have had success doing it.

I haven't taken it apart yet, but comparing what I can see to on-line photos of the GX200, the casting features look just like the GX200. As soon as I get some time I'll start tearing down & add some photos. The crack is on the bottom of the crankcase on the side opposite to the crankcase cover, right next to a mounting bolt. I'll only know how long it is when I get the motor out of the chassis.

I was thinking of drilling stopping holes, but what size would you suggest? Although the aluminum may flex a bit more than steel from thermal cycling, I'm also hoping it won't spread any farther. I just have to remember to keep a constant eye out for oil leaks in that area in the future.

Thanks

Drill stop hole need to be just a bit larger than the width of the crack.  The smaller the better.   The objective of the hole is to distribute the stress around the arc of the circumference of the hole rather than the crack  continuing on.  

Why not just buy the new (or used if you can find one) crankcase if the price is fairly reasonable?  If you want to re-sell it at some point, having a non-cracked crankcase (and non welded) will at least not scare the potential buyer away. Hopefully you can find a replacement. 

Ok, I pulled the engine from the chassis to get a better look at the crack (or should I say cracks). Looks like the whole corner is not far from coming off.  I wish the cylinder was separate from the crankcase. Here are some photos:

Also got some pics of the engine. I'm not expert but it looks a heck of a lot like a GX200 clone to me.









 

Looks like a tough fix.  Not sure if welding (weldings) will hold. The hairline crack will likely get bigger during heating and cooling cycles. 

Looks very similar to the engines CTC had on sale for less than $150.00

Not sure but I think they were LCT or Champion engines.  The 196cc is very similar to the Honda GX200 and from what I've read, parts are interchangeable.  You'd probably be better off getting a new engine and keeping the one with the cracked block for parts.