420 engines

[kevencyr]

hey guys, me again , is there a reason why i got 2 420 crawler engine, one is green and the other yellow, oil dip stick is different and piston in the yellow is a little bigger, also by comparing both piston, one look like its was made stronger, thickness of the piston is bigger on the yellow one. also got one removed, any idea how i could get the other one seized, so far no luck. thanks

[Col_CCC]

Unseezed? We lifted the front of ours w a chain fall. Then blocked the bottom and lowered it back down. Also fill the cylinder beforehand w auto trans fluid and let it sit for a few days


Chris

[Lavoy]

If the difference in bore diameter is 1/4", then one is a 420, the other is a 40. All 420, 430, 440 blocks use all the same internals.
Lavoy

[blakearmstrong2016]

yes soak soak soak with oil I also use pb blaster or marbrol mystery oil has worked many times well for me on marine engines

[Lavoy]

Large wood block, slide it down the bore and hit with hammer to loosen up. Steam cleaner with zero degree nozzle down alongside the piston to loosen the rust. Clean all the petroleum product of any sort out of the bore, and fill with water. Lots more, but that will get you started.
Lavoy

[gregjo1948]

I've had good luck using Coca-Cola.