Callin' inline6 GURUs

OldMercsRule

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Hey folks, I'm ponderin' puttin' together a 1350 with a 15" mid section, (short shaft).

Both 1250s I have do not have exhaust tuners as do my 1000s and my black block 1150s n' me 1500.

I have a 1971 parts (but complete with no holes in it) 1150 (silverblock). (Haven't taken it apart yet ta see if it has an exhaust tuner).

Question #1: Will the 1971 1150 bolt up to the 1968 1250 15" mid section? (I know the bolt pattern changed in the early 1970s does anybody know when it changed?) Guess: when they painted the blocks black in 1973 or some such. ;) (Me 1974 1150 is a black block).

Question #2: Did the 1350 have an exhaust tuner? (Me thinks not).

Question #3: What do I need to change to make the 1971 1150 silverblock a 1350? (Reeds n' the plastic restricters in the 1150 carbs is me guess). ;)

Question #4: Is the 1150 distributor the same as the 1350?

Hope somebody here who still posts n' cruises knows the answers to these questions so I don't have ta learn the hard way, (trial n' error). JR
:D
 

emckelvy

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Re: Callin' inline6 GURUs

1) Yes, the bolt pattern changed in '72 with the advent of the 1400's & 1500's. The 1150's had much smaller ports than previous iterations such as yours. I can't recall if the 1250 had the extra small studs in the bolt pattern, but you could always remove them if necessary. Or, just transplant a 1350 tuner plate onto the 1250 mid. Unka Thom (aka Dr. FrankenMerc) would know fer sur, he's had plenty of them in fronta hiz face recently!!!

2) The 1350 had a divider down in the round tuner going to the rectangular exhaust tube, but didn't have the split, thick tuner plate as did the later models. Whether this divider is still there or not probably won't make a ton of diff as to how it runs. If a divider is present and the bolts are loose, best to dismantle, replace bolts with stainless or monel, and reassemble with Red Loctite so they don't rattle loose. From what I understand, Merc had a problem with fasteners coming loose and then the divider plate would fall, blocking exhaust flow.

3) Yup, Reed Stops and Carb Venturi's are the principal differences, they just choked down a 1350 to 1150. Still has the Monster Ports. If I recall there was some slight diff with the exhaust manifold inner baffle plate, far as tuning goes. I expect that by now your 1150 probably has been upgraded to the latest iteration of the plate, if not it's probably not worth the trouble of messing with (unless you've already got it apart). Any gains made there would likely be slight compared to the tweaks done to carbs & reed stops.

Don't forget to rejet the carbs, most suggest going to .080" jets since they're easier to find and it's not going to hurt being slightly richer than the OEM .0785" jets. Especially with the garbage fuel we have nowadays!

4) Yup, don't need to do nuthin' with that except make sure it's working good! Seriously, if you haven't had it down for work recently or ever, I'd pull it apart, check the upper/lower ball bearings, and replace the pesky snap ring. I had that snap ring rust apart and break, the resultant shrapnel took out the trigger. Luckily that was back in the day when I could waltz over to NW Outboard Recycling in Pt. Orchard and get used distributors all day long for $50 or less. Not gonna happen anymore is it?!!!!

Anyway, that should take care of that, now it's time to get to work! The 1350 is one of my favorites and I regret selling the one I had. It was a great motor.

HTH...........ed
 

OldMercsRule

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Re: Callin' inline6 GURUs

Thanks ED!!!!

I luved me ol' 1968 1250 short shaft, (me first tower), got 'er goin' 74 MPH on a 14' Carlson tunnel.

Gawd did that engine have a hole shot with a 19p three blade!!!!!

I was swingin' a two blade ta get 74 MPH n' turnin' the revs up higher then I was comfy with.

I was told the 1250s were "grenades", dunno if it was true as #3 went in real cold water with me son hot roddin' it with very high hours on her......snif...snif...I miss that ol' girl..... :(

The ol' 1250 ate #3 n' I sold the 14' Carlson, (rated fer 85HP), stoooooopid stoooooopid stooooooopid.

If I make a new rod I'm gonna make a 1350 unless I find a short mid fer a black block!

Thanks fer the insight I was hopin' you would see this set o' questions n' step up!! Me thinks I should buy you an adult beverage one of these days when yer on the East side o' Puget Sound!!!! JR
 

emckelvy

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Re: Callin' inline6 GURUs

Man! That Carlson must've been a wicked ride! And I thought my 14' with 100hp or 16SS with 1350 were wild!

Guess a 1350 set up on a Hi-Po hull would really scream. Only a Power-Ported motor would have more guts, IMHO. Before I sold the Sidewinder (had a rotted transom), I threw a nice Stiletto stainless on the 1350 and took 'er out to the lake for one last spin. Scared the #%^%^! out of me, the tach was spinnin' the high side of the 6K mark, the 1350 was torquing the transom so bad I had to trim it way out, and the Sidewinder she was just flying down the lake!

I can only imagine what it'd do on a nicely-prepped tunnel hull.

Mebbe you and me and Mr. T will have to meet up one weekend this dank dark winter for some warm libations and good grub. Something to while the dreary day away while dreaming of warm summer weather!

Well, back to reality, tomorrow is reinstall powerhead on 30hp JohnnyRude, last person who worked on it didn't replace the base gasket. Tends to make 'em leak a bit!

One of these days I'll work on a Merc other than at Mr. T's. It'll be glorious!

Cheers.............ed
 

OldMercsRule

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Re: Callin' inline6 GURUs

Ya know Ed the ol' Carlson was surprizingly compfy @ 60 to 74 MPH. 'Specially on a 3 to 4" chop. I did have a power trim problem where it would stick and shock me by nearly blowin' over before I fixed it.

A friend of mine had a purdy metal flake blue 16' sidewinder with a 1500 on it that was much scarier, as it would chine walk in the 65+ MPH. We never knew how fast it was but it felt much MUCH faster then the Carlson. That was back in 1975 when the 1500 was new, (one of the main reasons I got the Tower o' Power bug), the run in the Carlson was 1994 when the 1250 was 26 years old!!!!!

If you are the same age as me, (likely), ya may have seen this Carlson on Hood Canal before I bought it in 1993. It was champane in color n' had a 1250 short shaft on it like mine and said "DORIS" on the bow, (after Daris Day), and would run around over there dominatin' any fast boat that showed up.

The hull was a 1968 (as was me 1250). I dunno if his 1250 was a BP (mine was not). GREAT SPORT!!!!! JR
 

OldMercsRule

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Re: Callin' inline6 GURUs

Hey ED! I was checkin' out an old tower on craigslist down in Olympia today fer me collection, (decided not ta buy), n' the feller mentioned he had an ol' Carlson in the back yard that I asked ta see.

IT WAS ME OLD RIDE^^^^^^^^!!!!

I guess the feller I sold it to was also a collector n' died n' there was a big estate sale with 40 plus old outboards, (mainly Mercs) a few weeks back on Whidby Island. Too bad I missed it.

Small world!!! JR
 

emckelvy

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Re: Callin' inline6 GURUs

Mebbe even smaller world than you think!!!!

Was this a gold Carlson with a busted transom and a 4-cyl Merc hanging (barely) on the back?

If so, we were drooling over it when I went up to the Island before the Big Sale!

I've attached a pic after it was pulled out of the Weeds where it undoubtedly had been sitting for years. You don't know how close I came to buying this but was disouraged by the severely damage transom.

If that's not the one, likely Mr. T saw yours, 'cause he was up there a number of times. I only got one visit to the Holy Grail. More motors and boats rat-holed around the island than I have ever seen (and probably ever will) in my life!

I have a few pics of the Carlson, they're too big to post here. If this was your old one and you'd like them, send me a P.M with your e-mail address and I'll forward to you........ed
 

OldMercsRule

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Joined
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Messages
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Re: Callin' inline6 GURUs

Mebbe even smaller world than you think!!!!

Was this a gold Carlson with a busted transom and a 4-cyl Merc hanging (barely) on the back?

If so, we were drooling over it when I went up to the Island before the Big Sale!

I've attached a pic after it was pulled out of the Weeds where it undoubtedly had been sitting for years. You don't know how close I came to buying this but was disouraged by the severely damage transom.

If that's not the one, likely Mr. T saw yours, 'cause he was up there a number of times. I only got one visit to the Holy Grail. More motors and boats rat-holed around the island than I have ever seen (and probably ever will) in my life!

I have a few pics of the Carlson, they're too big to post here. If this was your old one and you'd like them, send me a P.M with your e-mail address and I'll forward to you........ed

Yup that was it.

It was real weak, (tranny n' the front bulked under the bow), when I sold it with the 650 on it, (n' the ol' feller who bought it knew it).

I will send ya me addy in a PM, I would like some pics, (I don't know if I have any with the 1250 on it).

Sure wish I had known about that Whidby Island deal with all the Mercs, (musta ben sleepin' [unless I was still in Alaska]).

Got back late August (from Cordova) where I was all summer. JR
 
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