Bravo One Input shaft O-Rings

[sirhc76]

A few summers back my 7.4L Blew a head gasket and hydrolocked the engine resulting in a bent rod. Can be seen here if interested.

https://forums.iboats.com/forum/eng...98-wellcraft-240-se-5-7-issues-prop-or-engine

I ended up replacing the entire engine with a low hour engine. During the tear down of the old motor I realized the amount of half assery the previous owner had done and possible the reason for my issues. He installed the plastic "cup" that the Tstat sits on upside down basically blocking water flow. He also used a huge amount of RTV to seal the housing to the intake. My engine temps never got hot, I have to believe the T-stat housing wasn't making a good connection or the gauge was bad.

I also found several things that should have been addressed and did so while the engine and was out and lower unit off. Now that I'm putting the lower back on I have a question. The input shaft had a single o-ring on it although there are multiple grooves. My manual doesn't offer much on this part and Ive seen several pictures with a single o-ring up to 3. I now have a huge stash of Mercruiser o-rings and need to know how many should go on the shaft before installing it. Picture attached for reference.

Thanks all.

 

[Bt Doctur]

the critical ones go under the gimbal bearing, the middle may or may not be used depending on your coupler . If you have grease fitting on the Bravo coupler then use the middle O ring

 

[Bondo]

Ayuh,.... The twins near the knuckle lock the inner bearin' race to the shaft, Very important,.....

The single holds grease in the coupler,.....

 

[sirhc76]

OK, so the only o-ring that was installed when I pulled it was the o-ring next to the splines on the shaft. Was that another quality job by the previous owner who told me he had just changed the gimbal bearing? Should I also go ahead and replace the bearing knowing that there were no o-rings there? I have one along with the alignment tool/driver.

Thanks,

 

[tpenfield]

+1 to the twin groves. Slobber some marine grease on the shaft and the yoke so it does not rust any more. Did you grease the u-joints?

 

[sirhc76]

+1 to the twin groves. Slobber some marine grease on the shaft and the yoke so it does not rust any more. Did you grease the u-joints?

I'm going to clean all the rust of the shaft and hit it with some steel wool. I planned on greasing everything during the process.