OMC SternDrive Pivot Cap Cover

[Lyndy]

Although I do know what this part is called, I can not match it up with any drawing in all the manuals I have and BRP site. The Boat it came off is a 1974 Skipjack. The original motor has been replaced some time back so there is no Model number to refer to. The current Engine is a 96-98 Chevy 5.0 2BBL Rochester (Automotive Engine)The Drive has the following Characterics:

Upper Casing has "UPPER 21 17"
5 bolt Exhaust cover
High Profile

Till now I had figured it to be a 1974. I am not sure now. If anyone recognizes or owns a OMC Drive with this Pivot Cap Cover please respond here with what model year it is so I can replace my 74 manuals for some other model year.

Thank You

Pivot Cap Cover: Part# looks like 908199

Outdrive:

 

[Boomyal]

Re: OMC SternDrive Pivot Cap Cover

I have a '75 intermediate housing and your cap is identical. I think the left and right sides were identical. If you need a new cap, it is time to invest in a hose/flush kit instead. Voila! No more mickey mouse ears. The kit replaces one of the caps.

Did you get your rubber bumper figured out?

 

[Lyndy]

Re: OMC SternDrive Pivot Cap Cover

Hi Boomyal. I did not check the 75 model on BRP. I guess the corrected part # is 908499 instead of 908199. I did see a picture of a 1971 that did not have bumpers on it. As you may have spotted in my picture, I do not use Mickey Mouse Ears for that outdrive. The fact that yours is a 75, would that make mine likely a 75 or can this cap be used on older models?

 

[Boomyal]

Re: OMC SternDrive Pivot Cap Cover

As far as I know, they were used on all stringers ie electric, hydro-mechanical and mechanical shift drives.

As for the bumpers the trunion pivot cap you showed, was made to accomodate a bumper. That's what the two slot head screws were there for.

 

[Lyndy]

Re: OMC SternDrive Pivot Cap Cover

As far as I know, they were used on all stringers ie electric, hydro-mechanical and mechanical shift drives.

As for the bumpers the trunion pivot cap you showed, was made to accomodate a bumper. That's what the two slot head screws were there for.

Boomyal.. I have below Diagrams of a 74 and a 75 Intermediate Housing. You will see why I have been scratching my head on determining what I actually have. Notice on the 74 Drawing that no bumper is shown and the Pivot Cap Cover is shaped differently. On top of that it appears that certain 75 models were different as shown in the lower left of the 75 Diagram.

1974 Housing

1975 Housing

 

[Boomyal]

Re: OMC SternDrive Pivot Cap Cover

Hokay Lyndy, here's the best I got. I cannot account for the inset diagram on the '75 page but both styles of end caps are interchangable. The endcap you have was just sculptured to mate with the trunion cap that accepted the rubber bumper. To verify, check out the gasket shapes behind the '75 triangular end cap.

As for the bumpers, I have a '73 factory manual. Indeed it shows a trunion cap with an exposed zerk fitting on it. It was not profiled to accept the rubber bumper like your's is.

The missing year is '74. I have the '73 manual and a '75 outdrive to look at so I'm not sure when these changes were made. (rubber bumper trunion caps and triangular end caps)

Worth noting, my flush attachment, which replaces an endcap, is the earlier profile but it does not matter for function. I got my flush kit the year I bought the boat. I have seen the latter flush kit caps and they are the of the triangular shape. It is just cosmetic, as I mentioned.

So to make a long story short, you most likely have a '75 to '77.

Also, exept for the machine matching, both styles of trunion caps would be interchangable as well. You supposedly cannot even interchange a trunion cap with another of the same style because they are line bored, completely assembled, to keep the trunion bores true round, square to each other and the rest of the intermediate housing. They even have a special tool to verify that your bore axis is square in the event you have a traumatic encounter with your outdrive.

 

[Lyndy]

Re: OMC SternDrive Pivot Cap Cover

Thank You. The Hose Adaptor was going to be my next question. Since you say the two are cosmetic, which I can see from my looking at it, I will be getting it before Boating Season. Do thank you for all the insight. You want to swap 74 Manuals for 65 Manuals? HeHeHe

 

[Lyndy]

Re: OMC SternDrive Pivot Cap Cover

I have a '75 intermediate housing and your cap is identical.

Boomyal

The illustrations below are of two Pivot Cap Gaskets. The one on the left is the one I have. The one on the right is for a later model. The thing is they both have the same part number. Do you now which one actually looks like the one you have on your 75 OMC Outdrive regardless of the dates I have placed on them?:%

 

[Boomyal]

Re: OMC SternDrive Pivot Cap Cover

Don't know for sure without popping one of them off. However, I believe the two you have pictured are still the same. For the 68-72 gasket, I think you just flip it over for the opposite side. That is why they elongated the holes on the other one. It doesn't matter which way it goes. That, at least, is my surmise.

 

[Lyndy]

Re: OMC SternDrive Pivot Cap Cover

Don't know for sure without popping one of them off. However, I believe the two you have pictured are still the same. For the 68-72 gasket, I think you just flip it over for the opposite side. That is why they elongated the holes on the other one. It doesn't matter which way it goes. That, at least, is my surmise.

My Thanks As ALWAYS. It makes sense here also. Glad you said that. The one on the right is available on its own and the one on the left is only available in a Seal Kit for a little under $50.00

Lyn 8)