ted williams 4.5 hp tecumseh engine FUEL

[emtoly]

Does anyone have any suggestions or guidances as to whether or not I dare run my ted williams which has a standard 28:1 ratio on 50:1 fuel? My main outboard (merc) runs on that ratio and I"d like to run off the same tank.

There is a lean/rich adjustment knob on this unit, maybe this can be used to balance out the difference?
Thanks!

 

[steelespike]

Re: ted williams 4.5 hp tecumseh engine FUEL

Sears 4.5 appeared in 71.
My info says Eska 70-73 motors are 24:1 74 and later are 32:1 if TCW oil is used.
If your trolling, 50:1 probably would be ok.If your using it as a back up on a 1,000 lb boat not a good idea.If you cheat the mix with the knob you'll be back to the equivelent of 24-32:1 and a motor that stutters and is sluggish and dumps even more waste back into the water.

 

[mrcrabs]

Re: ted williams 4.5 hp tecumseh engine FUEL

My Eska 77 model calls for 50:1 but I usally run it 40:1 on these hot summer days and I took the lower coweling off for better cooling, I know my model has needle and ball bearings and with a good synthetic oil she should outlast me unless I were to blow it up in the test tank....lol, So I would say if you use a really good Synth oil in your merc you will be ok /w your 4.5, keeping it cool means a lot.
I hear alot about these new multi ratio oils...supposedly 50:1 covers everything...some call it Snake Oil...

 

[Tom @ Buzzard Bluff]

Re: ted williams 4.5 hp tecumseh engine FUEL

Does anyone have any suggestions or guidances as to whether or not I dare run my ted williams which has a standard 28:1 ratio on 50:1 fuel? My main outboard (merc) runs on that ratio and I"d like to run off the same tank.

There is a lean/rich adjustment knob on this unit, maybe this can be used to balance out the difference? Thanks!

Ask yourself this, "Do I have any reason to believe that the engineers who designed the motor didn't know anything concerning the lubrication requirements for it"?

It is either unknown or overlooked that the oil used in 2 cycle motors does more than just lubricate. The excess, unburnt portion that exits as exhaust waste also carries away heat. So it is a coolant as well as a lubricant. Since an air-cooled motor treads a fine balance between adequate cooling and melting itself can you afford to surrender the cooling effect of the recommended oil ratio?

 

[emtoly]

Re: ted williams 4.5 hp tecumseh engine FUEL

I think I'll stick to 30 to 1 ratio. What does TCW stand for SteeleSpike?

 

[ferd66]

Re: ted williams 4.5 hp tecumseh engine FUEL

the owners manual states 32:1 for these motors.

 

[k0rpl]

Re: ted williams 4.5 hp tecumseh engine FUEL

Prior to 1973 the 4.5 Ted Williams are spec'd for 24:1 using 2-Cycle Air Cooled Oil, NOT 2-Cycle Outboard Oil.

After 1973 It was changed to 32:1 again using 2-Cycle Air Cooled Oil. Such as you would use with a Chainsaw, Weed Whacker, Hedge Trimmer, Lawnmower, and the Like.

 

[leaguepark]

Re: ted williams 4.5 hp tecumseh engine FUEL

I've got a 4.5, 1973. The manual says 24:1.

The people on this forum have been great with advice. They know what they are talking about.

I wouldn't trust running mine on anything but 24:1.

Thanks again to everyone

c

 

[mrcrabs]

Re: ted williams 4.5 hp tecumseh engine FUEL

Ask yourself this, "Do I have any reason to believe that the engineers who designed the motor didn't know anything concerning the lubrication requirements for it"?

No, I believe they did know for a fact that there steel rods and moly rings would wear out quick unless well oiled.

All T 640 model engines up to Model 640-06 had steel rods w/66 needle bearings.
Begining with model T640-7A ( about 1973 ) tecumseh used a Aluminum Rod w/31 needles in a insert. They also changed rings at some point ie 50:1

 

[Tom @ Buzzard Bluff]

Re: ted williams 4.5 hp tecumseh engine FUEL

Beginning with model T640-7A ( about 1973 ) tecumseh used a Aluninium Rod w/31 needles in a insert. They also changed rings at some point ie 50:1

Presumably that juncture was when they started recommending the use of TCW-3 oil for water-cooled engines as well.

Perhaps I spent too much time around highly tuned racing motorcycle 2 strokes in my life, but I still believe in using oil formulated for specific uses. To me an air-cooled motor should use oil specifically designed for the wider range of temperature extremes to which they are subjected. Water-cooled engines---particularly thermostatically temperature stabilized models---can do well with an oil that wouldn't do the job in a higher stressed air-cooled engine subject to far broader temperature extremes.

The worst case scenario on our air-cooled motors is in the case of a waterpump failure that goes un-noted. I can readily imagine that engine suffering more damage if it is on a diet of TCW-3 than if it's using oil designed for the greater temperature extremes of air-cooled usage.

I just found a 'steal' on a gallon of Klotz 'Technipower' full synthetic this week. We used to use it on racing motorcycles that were subjected to far more extremes than our little Tecumseh engines so I think my air-cooled motors will be very happy with it.

 

[mrcrabs]

Re: ted williams 4.5 hp tecumseh engine FUEL

Klotz

klotz what? exhaust ports???

Happy Labor day

 

[freeisforme]

Re: ted williams 4.5 hp tecumseh engine FUEL

................................................

I just found a 'steal' on a gallon of Klotz 'Technipower' full synthetic this week. We used to use it on racing motorcycles that were subjected to far more extremes than our little Tecumseh engines so I think my air-cooled motors will be very happy with it.

There's a name I haven't heard of in years! I used to run that stuff in my dirt bikes back in the 70's and 80's. I probably still have a case of it in cans out in the garage.