1957 35 hp rde-19c lower crankshaft seal

[seahorse44]

I have a new seal for the lower crankshaft and it is a hard carbon seal with springs on it . My question is does the flat side go toward the bearing or the raised carbon side go toward the bearing . is there a gasket under the seal against the bearing ? I was getting a lot of gas and oil in the water and using a LOT of gas while running and rough idle. any help is greatly appreciated . thanks

 

[Paul Moir]

Re: 1957 35 hp rde-19c lower crankshaft seal

Welcome to Iboats!<br /><br />The flat, shiny side goes toward the bearing. The seal, spring, clip and protectors rotate with the crankshaft, so there is no sealant between the carbon and the bearing. That is to say, the rotating seal surface is not the rubber quad ring, but rather the carbon seal itself.<br /><br />Right next to the lower crank seal & bearing is the crankcase fuel drain. This is the outlet of the little valve on the very bottom right of the front of the block. This valve collects puddled fuel/oil from various places in the block and dumps it overboard.<br />If you run rich, or there's a hole in the fuel pump diaphram (if present) then extra fuel will puddle.

 

[seahorse44]

Re: 1957 35 hp rde-19c lower crankshaft seal

Paul,<br /> Thank you very much for your reply. I had the seal in wrong as I suspected. Fuel pump is rebuilt . motor run 6 gallons of gas through it in a couple hours of running slow and the gas in the water had me worried . motor running rough at idle too. figure this leak may cause all of this. <br />It was bubbling around seal just turning by hand .<br />thanks again . seahorse44

 

[Paul Moir]

Re: 1957 35 hp rde-19c lower crankshaft seal

No trouble at all! Congrats on the non-trivial task of pulling the powerhead too. <br /><br />6 gallons in two hours at below 1/2 throttle sure does seem excessive. Not way out of line for these old engines though; they're pretty inefficient at speeds other than around 3/4 throttle (cruise). And a leaking crank seal will give you a nasty idle. Try pumping the primer bulb when you're running - if it burbles the needle & seat in the carb may be leaking. If not, just pop the knob off the idle mix and adjust it in (CW) to get your best running.