[Randy Lahey]

I just picked up a 1984 Tecate. The engine is stuck. I took the head off, and there is a yellow gel on top of the piston/head. Any idea what this is caused from? Also, can I remedy this problem with out a top end rebuild?

 

[Qtown]

If the engine is froze up your probably in for a rebuild. Id try getting that goop off the top of the piston and putting several ounces of penetrant of you choice on top and let it sit for a couple days. Then take something like a cut down 2x4 that covers much of the piston top and easily tap on it with a hammer. See if that knocks the piston loose if thats whats froze. Although I dont see any rust in the pic if it had water/coolant in the bottom end you may have rusted/pitted and scored bearings and its time for a major rebuild.

 

[auburn6887]

the goo can be algae from ethanol from a leaky carb.

follow above advice or just pull the jug

 

[NMKAWIERIDER]

I don't see any rust or reason for the piston to be seized. That's probably someone's attempt to free it up. Probably had a bottom-end issue. Try to turn the crank but go easy on it...