Johnson QD-16 base gasket

[Steve D]

Well, you could do either one I guess, just don’t expect too much difference as Frank said, if you do the baffle and 2 gaskets.

[frankr]

OK, after some more digging, I went to the 12hp Gale parts books.

1955 Gale, not applicable because it still used the old-style exhaust housing.

1956-57 Gale used 303892 gasket, same as shown in 1955 Johnson book.  No baffle yet.

1958 Gale used 377070 Baffle & Gasket kit. It also shows the gaskets available separately as part number 302588 (use two) in case you already have the baffle.  This is what led me to be surprised that it was used as far back as the ’55 Johnson.

Yes, depending on where you look 303892 does supersede to 302588 (use two) and/or 377070 baffle and gaskets kit.

My opinion: Use whichever you prefer, 377070 baffle & gaskets kit, or two 304588 gaskets without the baffle (two because they are thinner than the old original 303893).  Again, my opinion, the whole matter came about as a fix for a bad design where the crankshaft poked down into the exhaust housing along with crummy seals on the 12hp and 15hp motors.  The crummy seals still failed, baffle or no baffle.

 

.

 

[Steve Martin]

Thanks to all for the info.  Since I had both solutions on hand I went with the baffle setup.

[fleetwin]

OK, well that is strange.  I wouldn’t think that the gasket/baffle kit would have even been available in 1955.  This engine has the nice carbon seal set up for the lower crankshaft seal, so I would just use the original 303892 thicker gasket, the baffle isn’t needed.  But do make sure to clean out the crank/driveshaft splines and lube them liberally prior to gearcase installation.  Don’t put the moly lube on top of the driveshaft though.

[Author]

Posts