Penton Owners Group

General Discussion => Penton Talk => Topic started by: Todd Rovello on March 26, 2014, 08:54:48 PM

Title: Sachs Cylinder Head Stuck
Post by: Todd Rovello on March 26, 2014, 08:54:48 PM
I am disassembling a Sachs 125b motor and the cylinder head is stuck tight to the cylinder. It just won't separate.. and yes I removed the 4 head bolts. Tried tapping it with a rubber mallet, putting a sharp putty knife between the jug and the head to no avail. I am concerned about breaking the cooling fins. Would a little heat help? Any suggestions?
Title: Sachs Cylinder Head Stuck
Post by: Kip Kern on March 27, 2014, 07:07:28 AM
With the head removed, I beat the piston out by suspending the engine slightly above the ground clasping the cylinder between my knees.  The engine weight and pounding force free the piston from the cylinder and doesn't damage the rod.  Rebore and fit new piston and you are there.  I use a 2 lb hammer and copper drift slightly smaller than the diameter of the piston. Spray some PB blaster around the piston and heat around the dome/cylinder area if really stubborn
Title: Sachs Cylinder Head Stuck
Post by: AndyL on March 27, 2014, 08:36:11 AM
Ditto to Kip's method.

But I always seem to use a good piece of 2x2 hard wood instead of the copper drift.

Andy
#14u
MOVMX, AMA, AHRMA
Title: Sachs Cylinder Head Stuck
Post by: hankthecrank on March 27, 2014, 09:06:37 AM
Welcome Todd. I think if the head is stuck on the barrel,I would try gentle heat on the joint between the two and try tapping on the solid parts of the head with a long drift, brass or wood, an gently shock the parts. With the drift you can reach down past the fins and set up a resonation in the aluminum with some gentle taps. I;ve separated alot of aluminum pieces this way. Good Luck! Hank

Hank Rinehart
Title: Sachs Cylinder Head Stuck
Post by: Kip Kern on March 27, 2014, 02:06:17 PM
OH, I should have read the post better.  Remove a stuck head!!  If all bolts are out, I use a dead blow hammer and tap sideways on the lower edge of the bottom fin on the head so it sort of twists around.  don't hit the side of the fins as they will break.  Sorry, I need to pay attention better:D  The wife tells me that all the time[:p]
Title: Sachs Cylinder Head Stuck
Post by: thrownchain on March 27, 2014, 02:30:58 PM
If the motor is not stuck, remove the cylinder as a unit, then you can tap the head from the bottom side.
Title: Sachs Cylinder Head Stuck
Post by: Todd Rovello on March 27, 2014, 08:58:12 PM
Thanks guys. All good tips. Kip, my wife says I don't pay attention either.
Title: Sachs Cylinder Head Stuck
Post by: tofriedel on March 28, 2014, 11:15:40 AM
If the piston is not stuck, have you tried kicking the engine over and let the engine compression lift the head away from the cylinder?

No damage would insue.

Tony