Sachs engine problem..need help !
 

Hi all, I recently purchased a "new" Sachs engine that has never been run or at least since factory run some time ago. The engine will start and idle fine but on run up it surges and sounds like it misses and burbles at mid-high end and just won't top out. I am turning a 22x10 wood prop and the engine is a older Sachs 3.4 with CH ignition. Spark is good and a carb kit was just installed but it seems to be doing the same thing. I started with both high and low speed needles at 2 turns out and worked it around from there. I can get a great idle but slow transition with a surge and burble at high end. At about 3/4 throttle it seems to run best. Any ideas on these engine settings would be greatly appreciated.
PS: I am running a break in 32:1 fuel mixture and it starts on first flip. Thanks

RE: Sachs engine problem..need help !
 

You probably already have, but check the timing and try opening up the spark plug gap to about .035...Too much spark advance will cause missing at wide open throttle...

RE: Sachs engine problem..need help !
 

Hi rcIgn1 , I don't have enough knowledge on how to check the timing on the engine......any suggestions on how I do that? Thanks

RE: Sachs engine problem..need help !
 

Take the spark plug out
Turn on the ignition
Rotate the crank slowly CCW
When you hear a spark make a mark on the hub and another straight across on the case
With the piston at TDC and the throttle wide open the two marks will not coincide
Measure the diameter of the hub at the point where the mark is, multiply by .244
The two marks should be that far apart to fire at 28 degrees BTDC
Adjust the link from the carb to the timing ring to get that measurement :D

RE: Sachs engine problem..need help !
 

Seems like if i'm doing it right im coming up with .28300........is that the 28 degrees BTDC? Maybe I did something wrong? Pic included at Wide open throttle and Top dead center. There was a couple marks from the factory on the hub already so it may appear kinda confuseing. Thanks