Omc Ft-10s

[brichter]

I am looking for any info on these OMC race engines such as photos, tech info or specs sheets. I have most of the parts for one of these and I think I am going to put it together in as close to the original configuration as possible.
For those not familiar, FT-10S is the designation for the 3 cylinder, 49.7 ci motor that was approved for the UIM SE class around 1968. A special mid with linkage on the side was used to adapt the 14:23 GT115 type lower unit. Pictures of the hood graphics, dressed powerhead or shift linkage would be especially helpful.

[Mark75H]

Hope this is helpful.

http://i43.tinypic.com/nxn81z.jpg

[Lars Strom]

Hi Brichter,

I use to own one..a Johnson..More or less a stock 1968 55hp power head
on a special mid section.
X/GT 115 hp gear case and the shifter on the side of the mid section..

Ft 10 S used the standard transom brackets and no power trim..

1973 OMC came out with a better one..Named 65 SS

A modified stock 65 hp power head..different cylinder head and exhaust ports..

Same mid section, gear case but factory power trim from V-4 racing..

I won the 1973 European SE Champion ship with that engine..

Maybe have some better photos..

[Lars Strom]

This is my 1973 lower unit, but FT 10S look the same..

[Lars Strom]

Hi again..

On the right side of this photo you can see a FT 10 S mid section..

Repainted in Johnson Stinger colors..

Regards

Lars

[brichter]

Thank you for posting those Sam and Lars!


Lars,When you say the standard stern brackets do you mean the aluminum type used on the service motors at that time (like the orange mid in the picture)? My mid has that same type but I am not sure if the FT used those or the steel GT115 type bracket.
Stock 55 hp powerhead is what I figured was used. Do you remember if a flex flywheel was used on the ft10 s?
Thaks again!
Bill

[Mark75H]

Line 6 c

FT10 S flywheel ... 7 pounds 11 ounces ... if that's what a stock flywheel weighs ... I'd bet the FT10S flywheel is not a flex

[wolfgang]

Line 6 c

FT10 S flywheel ... 7 pounds 11 ounces ... if that's what a stock flywheel weighs ... I'd bet the FT10S flywheel is not a flex
My buddy H Tinscher and myself raced what must have been the first FT10S in Germany.
Flywheel was a cast (potentially press-formed) massive aluminium affair. They appear occasionally on ebay. That heavyness led to accelerated wear of the top crank bearing and leakage through the seal there, disabling the ignition. The transom items were cast steel, otherwise the cross-bolt threads would not live long enough. I remember them being heavy when I installed them. Transom thru-bolts however were some super-duper high-strength aluminium alloy. Titanium wasn`t in use at that time yet (except as con-rods in the Porsche race engines). Powerhead was indeed stock 55hp. We took 1mm off the cylinder head, removed the airbox and fitted little handmade brass stacks to the carbs (imitating the Carnitis). We slotted the cowling to the left and right of the carbs and rejetted. Underneath the two rear mounting bolts of the lu, the exhaust housing was cross-drilled, 13mm dia. Engine would pull best at about 7200 rpm. We had four ss props made in Sweden (SB Man AB I think it was), after seeing them used by those Scandinavians who raced the NSU Wankels in 2ltr inboard. Fantastic props at 60% the price of the Radices. If my memory serves me right, the props were pitched 17 and 18". Three-bladers worked best, four blader was disappointing, might have needed more work.
A year or so later(`69), the German Johnson distributor (Dr. OE Hesse) gave us a fresh engine from Bruges, which enabled us to win that year`s Liege and Berlin 6-hour races, with a heavy Dalla Pieta` winged Vee-bottom (which he also paid for). A 65ltr tank would last us 1 1/2 hours. Great engines. Pity I don`t live in the US - might be tempted to race Mod-E with the 3-banger.

[Lars Strom]

Thank you for posting those Sam and Lars!


Lars,When you say the standard stern brackets do you mean the aluminum type used on the service motors at that time (like the orange mid in the picture)? My mid has that same type but I am not sure if the FT used those or the steel GT115 type bracket.
Stock 55 hp powerhead is what I figured was used. Do you remember if a flex flywheel was used on the ft10 s?
Thaks again!
Bill

Hi again,

Standard aluminum stern brackets..same as the 75 short shaft (15 inch)
motor.

The flywheel was stock and a weakness was the two breaker points under the
flywheel..needed cleaning and service often.

1968 was the first year of the 3 cylinder looper and I think OMC made a mistake using the X/GT 115 gear case..took away to many horses just to turn around..

Same problem with my 65SS 1973..
The year after.. (1974) the same power head with standard mid section and the new Nitro gear case made my SE boat 15+ MPH faster..

[Lars Strom]

Please, check my Racing stories..many pages about Evinrude 3 cylinder
racing..



http://www.boatracingfacts.com/forums/showthread.php?t=6727

[Bill Gohr]

Billy, that center section you are using had a GT clamp bracket on it when I got it, we took it off.

[brichter]

Line 6 c

FT10 S flywheel ... 7 pounds 11 ounces ... if that's what a stock flywheel weighs ... I'd bet the FT10S flywheel is not a flex

Oops, missed that row, I agree, stock cast wheel.

[brichter]

Hi again,

Standard aluminum stern brackets..same as the 75 short shaft (15 inch)
motor.

The flywheel was stock and a weakness was the two breaker points under the
flywheel..needed cleaning and service often.

1968 was the first year of the 3 cylinder looper and I think OMC made a mistake using the X/GT 115 gear case..took away to many horses just to turn around..

Same problem with my 65SS 1973..
The year after.. (1974) the same power head with standard mid section and the new Nitro gear case made my SE boat 15+ MPH faster..

Wasn't the new 75 hp powerhead legal in 74?

[brichter]

Billy, that center section you are using had a GT clamp bracket on it when I got it, we took it off.

What about the swivel? Was it the same one that was on there when I got it?

[Lars Strom]

Hi again,

The Evinrude 75hp came out first 1975..but the 70 hp 1974 we raced was more or less like a 75hp with the nitro gear case..

[taatto]

59014

Is this ft10s?

[Lars Strom]

Yes I think your mid section is from a FT-10s 1968 model year taatto.
(Not 1971)

[Lars Strom]

I don't know what a FT-12c was.

[Lars Strom]

Here is a better picture of my Evinrude 65 SS 1973..
I think the model number was FT-16B

[taatto]

Does anyone have a picture of that shifter cable bracket? I have that shifter lever, but I don`t have that bracket. So I must make that.

I have that green(Johnson) FT10 transom and gearcase. I am building 1970 60hp powerhead to it. But I use newer pistons and crankshaft(70hp). So I get newer ignition to it.

[Selvaracer]

Better pic of that middsection and lower+ shift lever,that Taatto means.606916069260691

[kilpavenenostalgiaa]

(I lost my passwords so this is my new account. So I'm taatto.)

My FT10S was without engine cowl until last week when I bought 1968 year model Johnson 55hp engine cowl.

http://tinypic.com/r/2rggmyd/9

Does anyone know the differences between engine cowls of FT10S and normal 55 outboard? I'm wondering if I have the right cowl now.


Here's the real FT10S, I think in these to pictures:
http://tinypic.com/r/2q2qwif/9
http://tinypic.com/r/16a1ron/9

1970 Similar engine but Evinrude. I wonder if they changed the powerhead to FT10, 55 -> 60

http://tinypic.com/r/11vmeix/9