What mids on I6 interchange?

[fijjity]

I have a 71 I6, so anything up to 72 will be okay. How far back can I go? I am swapping in a 15" for a 20" and my Merc manual says that to use trim system before 67, you must use a heavy duty swivel clamp. Enlighten me as to what I years I can use and if its safe. Thanx

[Raceman]

You've stumped me with that one. I've got a good bit of stuff from back in the 60's, but haven't paid much attention to details of it. I can't imagine an earlier swivel bracket being heavier duty than the early 70's one, and I know the 70's trim system will interchange with everything I own unless there's a lower shock mount diameter issue that I'm not aware of, and if so I'd think it'd be easily fixable.

[fijjity]

Mercury outboards 1966-1974
Section 7-Accessories
Part C-Power trim
Page 7C-3 under "Description" heading
"CAUTION: Do not attempt to install trim kit on pre-1967 engine without
first installing heavy-duty swivel bracket, or failure and
serious damage may occur."

I wasn't sure if there was somethin with the pre-67 mids(which there are a lot of) that I couldn't use on my 1350 with trim to convert it from 20" to 15" mid. Just checkin before I waste money on a short shaft engine that I can't get to work on my 1350. The guy says its a 115, serial number 1577673 which the 115 doesn't start that low. I thought the mid might work for me.

[largecar91]

I am not sure how far back you can go, I think back to the early 60's. The 72 and back 115,as well as all the inline 6's and the 4's from 65 horse and up will bolt up but the 72 140 and 73 and up 150's will not bolt up. I have swaped a bunch of trim parts around on different mids and never found anything but minor differences in the mids. here is a whole running 65 hp short shaft on E Bay now. http://cgi.ebay.com/ebaymotors/65-Horse-Mercury-Outboard-Runs-good_W0QQcmdZViewItemQQcategoryZ111124QQihZ015QQitemZ250002831149QQrdZ1

[Raceman]

72 was the only year Merc ever made a shortshaft 115, so that one probably ain't an option, although it would have the old style bolt pattern.

[fijjity]

Well, since you have swapped various years, I feel better about it. This guy that has the 115(or so it's called) also has a 65 he wants to part with. He is a scrapper, so these are ones he doesn't have to tear down, check condition, or part out. I may get 2 for the price of one.
Them stax went for a bunch on ebay didn't they? :eek:

[Raceman]

Them stax went for a bunch on ebay didn't they? :eek:

Yep, very disappointing. I was the high bidder and have sent a couple of E mails asking just what it'd take to buy em, but so far no response. I desperately need one of the elbows to complete an engine.:( It's really surprising how these things keep turning up in broken sets. I had a complete setup with all the plates and cowls already and found 2 on E Bay about a year ago. I've seen one other pair of em sold. Since Merc only sold em in 3's I just don't know how they seem to surface 2 at the time.