Mercruiser R drive question

[84EdH]

I just replaced the water pump/impeller on my R drive. When inspecting the upper housing, I see an 0 ring halfway across the opening to the part the drive shaft splines will go into. Is this supposed to be there? There was an O ring on the drive shaft groove when I disassembled. Also, I watched Chris video on water pump service from the stickies. the seal he flicks out of the upper unit, what is its purpose? what is it called? help appreciated.

 

[84EdH]

Re: Mercruiser R drive question

Here is a photo of the o ring hanging in the opening just above the seal. (the little squiggly piece looks like a tiny bit of the rubber on that seal splitting away.)

 

[Eric 3.7LX Alpha 1]

Re: Mercruiser R drive question

No it doesn't belong there.... looks like the O-ring that Mercruiser omitted on later drives. The O-ring is installed in the groove on the shaft of the lower half, just below the splines at the top.... which runs thru those seals..

see attached photo of the O-ring installed.

 

[achris]

Re: Mercruiser R drive question

I just replaced the water pump/impeller on my R drive. When inspecting the upper housing, I see an 0 ring halfway across the opening to the part the drive shaft splines will go into. Is this supposed to be there? There was an O ring on the drive shaft groove when I disassembled. Also, I watched Chris video on water pump service from the stickies. the seal he flicks out of the upper unit, what is its purpose? what is it called? help appreciated.

It's called 'oil seal, drive-shaft housing - lower'. Its purpose is to seal on the lower drive-shaft (the one coming from the gear housing) to stop water entering the spline cavity. The upper drive-shaft (in the drive-shaft housing) which has the female of the splines also has a seal on it to stop the oil in the drive from leaking into the same cavity....

Part number is 26-965031. I replace it as mandatory whenever I service the water pump...

Chris......

 

[84EdH]

Re: Mercruiser R drive question

thanks Eric. thanks Chris.