Originally Posted by naftali

Hi all,
Here is my latest problem with my DZ 170 glow: WOT with APC 19x11 is no more than 5400 RPM. Idle is 1700. Acceleration smooth.
The engine ran at WOT giving 7200, until one day it got stuck at 5400 no matter what I did trying to remedy it: One change at a time.
Replacements:
- Piston Ring Sleeve
- Head assembly
- Head gasket
- Bearings
- Pump Diaphragm
- Glow plug
- Carburetor insulator
Actions:
- Polishing cam followers
- Verifying valve lash, cold and hot
- Verifying valve timing
- Making sure the crank pin sits in the correct groove of the disc valve of the back plate
- Making sure there are no leaks
- Fuel consists of 20% Morgan LS oil, 30% Nitro, 50% methanol
- YS mount intact
- HS needle 1 turn open
Any idea on how to fix the problem will be appreciated.
Thanks!