outdrive foot

[iknowalttl]

I have a Rinker Captiva with a 4.3 and alpha one gen one outdrive... was going to replace the impeller and noticed a little heat damage to the base of the water pump so I was going to replace it... when I pulled the base out I noticed that the bearing seal was not built in to the base like a different drive I have apart and the replacement part I have has the seal built in and the bottom where it mounts is extended with a place for an O ring... I also noticed that the shaft on the drive I was running has play side to side so I assume the bearings are worn... the kit will fit the other drive foot and the shaft is nice and tight... all else seems the same except it has a pre load pin in the top of the shaft... so I want to know if the foot part of the outdrives interchange? I want to put the foot half of the outdrive with the load pin on the top half of an outdrive where the foot did not have the load pin... am I looking for trouble or will this work just fine?

 

[Scott Danforth]

There are 7 generations of 4.3 and 4 different drives behind them.

So WTF do you have. Be specific with year and serial number. We are not mind readers.

 

[iknowalttl]

working on 1989 Rinker with a 4.3 mercruser and alpha one gen one stern drive OC798464.. when separating the lower half it has the shaft without the load pin... I also have a 1989 Regal with a pair of 5.0 mercruisers and alpha one gen one drives... I have one of the lower halves taken off the Regal and it has a pre load pin in the top of the shaft... what I am thinking, if there are no issues, is to put the lower half with the load pin to the upper half that is still on the Rinker that originally did not have the load pin... can't get Regal serial number at the moment...

 

[Rick Stephens]

That sounds like the correct and proper stuff for any alpha one drive. As always, I strongly recommend you pull the entire drive and split the cases on a bench instead of just pulling the lower. Saves time, seals, and makes everything easier. the shaft coming up from the lower is not held tight except under load.

 

[Bt Doctur]

Pry that part out of the lower unit, it was originally in the base of the water pump housing

 

[iknowalttl]

Pry that part out of the lower unit, it was originally in the base of the water pump housing

gotcha... but after seeing the free play in the shaft from the lower unit with no load pin, I'm thinking I would be better off using the other bottom half with load pin if it will work properly... it's not end play (in and out play)... just not sure if the 2 are interchangeable...

 

[Rick Stephens]

It is supposed to have play in it when not under load.

 

[achris]

.. it's not end play (in and out play)... just not sure if the 2 are interchangeable...

Lift the shaft while checking for movement. I think you'll find it's gone. That's the design...

The MC-1/R gear housing and the MR/Alpha One gear housings are completely interchangeable. Although, some people get the idea that they need to cut the pin off. :facepalm: Don't do that...

Chris....

 

[iknowalttl]

Pry that part out of the lower unit, it was originally in the base of the water pump housing

thanks Doc... did that and all looks like I am used to seeing... I haven't done many of these and that was the first time I have seen the base in 2 separate parts... I'm not sure if it broke or was made that way but it was very clean mating surfaces where they parted... the new one didn't look like it would come apart... didn't try, just looked it over out of curiosity, installed the O ring, greased it up and put it in...

thanks for the input Chris and Rick... the play had me worried, especially when the other lower unit which has the load pin was nice and tight feeling... I guess it is just the difference in the models and how they are designed... I lifted up on the shaft and everything seemed tight and felt as I thought it should... I ended up putting same lower unit but good to know that the 2 are interchangeable... making sure I am ready to go get some of them scallops... that time is near for the arm pit of Florida...

 

[iknowalttl]

I was also wondering about the O ring up near the spline... I replaced it but it seems I was reading somewhere about it being better to leave it off... something about preventing rust... the few I have taken apart haven't had any rust issues and I have just coated everything well with grease and installed with the O ring just as it was when taken apart...

anyway, question is what is best replace O ring or delete O ring?

I was just reading another post and noticed a comment about not getting water to the impeller when using a bucket for a sterndrive... I have been doing that with a 30 gallon short drum and thought it would be as good or better than muffs... but I am also replacing heat damaged water pump base on my drive... would anyone mind to enlighten me a little on this?...

 

[achris]

Be a cyberman. Delete the O ring....

With a drive in the drum, usually the water level isn't high enough to flood the impeller, so you get a dry run. Those pumps aren't 'self-priming', they only pump water when the water is presented. On muffs/flushers, the water is presented to the intake side of the pump by hose pressure, and the pump's happy with that. When the boats is running, the shape design of the intakes helps push water up the the pump, so again the pump's good.

Chris......

 

[Bt Doctur]

you dont understand how it works The gears are cut to pull the pinion gear down on a MC1 or any drive with a preload pin. The drives without a preload pin push the pinion upward . To set the gear end play in one of those drives the tool pulls the shaft upwards into the bearing race.

 

[achris]

you dont understand how it works The gears are cut to pull the pinion gear down on a MC1 or any drive with a preload pin. The drives without a preload pin push the pinion upward . To set the gear end play in one of those drives the tool pulls the shaft upwards into the bearing race.

YOU don't understand gears! All gears set at 90 degrees (ie, pinion and drive gear in this example) will always try to push apart under load. And THAT is the sole purpose of the preload pin! The 'preload pin' is there to push to keep them in correct mesh, as the drive shaft bearing has the taper facing towards the pinion, and needs the preload pin to keep it in proper contact.

From MR on, the driveshaft bearing was turned over and the separating force of the pinion and drive gears keeps the bearing running properly. Hence it feels 'sloppy' when the drive shaft drops down slightly, due to it not being forced up by the spinning gears.

Chris.......