"Pinning" prop shaft bearing carrier housing to gear case?

[oldschoolnc]

Mines a 96 Johnson 225. Both intake and exh. port work, pistons, heads, reeds, 135comp... ect..ect. lower has a bobs lwp kit, and is highly modified. I have read they don't like surfacing props...With regards to pinning, My Question is, do I just drill and tap a hole one each side of the gear case n carrier, locktite in set screws, or just tap the carrier housing, and put in countersunk phillips machine screws, that in theory, will pull the two together? Any thoughts or suggestions will be appreciated! It is going on a Stream valero yt, thats been on a serious weight loss program...lol. 10"set back plate... currently have a new 30p Signature "semi-chopper" or "clopper" as an inexpensive starting point. The prop has been to my prop shop and some needed reworking was performed......THANKS AGAIN! Happy Flying!

[oldschoolnc]

This is what I am working with. Watcha think? Good or Bad.....

[outboards4life]

counter sunk bolts through the gearcase housing and carrier at about 10 2 4 and 8. Did that to a v8 case a long time ago. Didn't have an issue since. They will occasionally break a bolt though so you have to keep an eye on them.

[rude tim]

You cut off the plate above the prop? Have you ran it that way before? I tried cutting mine and the prop slipped like crazy. Hope it works for you.

[oldschoolnc]

Thanks, outboards4life. Sounds like a plan....

[Instigator]

Search pinning a carrier, posted by me in tech.

I did a post yrs ago showing pixs, measurement etc.

Nice looking gear case BTW.

[rjdubiel]

they break when you over tighten the bolts that pin the carrier to the case. I lightened up on them, check them every so often (every time I go out) and have not had one go missing since.

[rjdubiel]

I was talking to a buddy last night and he reminded me that these cases do not need to be pinned. I have not taken one apart but he has done hundreds of not far more over the years. He was talking about the tabs and bolts that you see holding the carrier in the case. He was telling me why but I didnt follow it completely as I have not played with any lowers yet besides some seal replacement. I think I have some things to learn this winter! His statement telling me why ended with "Merc should have copied OMC on this one!"

[oldschoolnc]

I placed four 1/4 20 stainless countersunk bolts W/stover type lock nuts at about 10,2,4:30 and 7:30,o'clock positions last night. I Don't think it will hurt.... I have read of
weakness in that area when running high pitch surfacing props....

[rjdubiel]

Looks like late 1990 is when OMC starting using that locking tab and bolt for the back of the carrier. So if yours is a 1996 lower you modified I am thinking you do not need to pin that carrier since that tab is in there to keep it from working its way back out towards the prop. Correct me if I am wrong please.

[rjdubiel]

I placed four 1/4 20 stainless countersunk bolts W/stover type lock nuts at about 10,2,4:30 and 7:30,o'clock positions last night. I Don't think it will hurt.... I have read of
weakness in that area when running high pitch surfacing props....

With how easy it is to do extra insurance is never bad.

[oldschoolltv]

All omc lowers need to be pinned if surfaced they will wear a big groove at approx 4-5 o’clock once it gets too deep you start breaking the carrier. I pinned mine 10 years ago and would break a bolt every couple of months until it finally wore a groove, so I had to have a custom carrier built to span the groove a quarter inch each side, best advise is pin it early and check bolts often. Matt

[oldschoolltv]

New carrier.

[Speed Jr.]

That case would be more effective on a light weight race boat....Not so much for pleasure boating as you'd benefit from having a cavitation plate, especially for getting on plane. Nice piece though.

Jr.

[oldschoolnc]

Yeah, Lower is going on a lightened up stream valero yt..... Thanks for your comment. 10" setback sound about right for this hull? My first HydroStream... Motor was alleged to have
been dynoed, 285 @ propshaft...said it was done by "evolution marine". Anybody ever heard of them? I scoped it and can see extensive exh. port work, and some intake work, relief's filled, from what i can see.. Big bore carbs, and composite reeds. Do HP#'s sound feasible? Been boating 40yrs. All crossflows. My first looper. Thanks for any reply.