1976 Johnson 55EL76 Piston Part number changes and piston design?

[n8800ss]

Hello,

I recently had my 76 55 hp johnson bored .30 over and had new pistons ordered by the shop that did the machine work. The pistons have a new part number from BRP and the skirts of the piston are different for the intake and exhaust ports. The ports look like they line up with the cylinder, however, the stock pistons have closed ports and the new pistons are open at the bottom of the skirt.

Did BRP change piston design for these engines or did the machine shop order the wrong pistons? I unfortunately dont currently have the piston numbers from the ordered parts but from talking with the folks at boats.net the old part number is 388204 and the new is 396759.

Thanks in advance.

 

[oldcatamount]

Re: 1976 Johnson 55EL76 Piston Part number changes and piston design?

This is a link to marine engine.com concerning your piston question: http://www.marineengine.com/parts/j...urer=Evinrude&section=Crankshaft+&+Piston. It looks like the part numbers have changed at least 4 times but I'm not sure if the design changed or not.

 

[n8800ss]

Re: 1976 Johnson 55EL76 Piston Part number changes and piston design?

It appears as if they changed the piston design. This is interesting... Has anyone else experienced this? I'm curious what the difference is and if it was done for a known problem with the original design.

Thanks!

 

[n8800ss]

Re: 1976 Johnson 55EL76 Piston Part number changes and piston design?

Nothing?


The design has definitely changed and appears to be similar to pistons on later models.