2 St.Tohatsu 70 HP.-

Sea Rider

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Paul, for engines that has automatic oil pumps. Is it possible to use 25:1 fuel oil ratio mixed just on tank and leave engine's oil reservoir completely empty untill break in period has finished ? Could there be a oil pump damage of some kind by not filling it ? Owner's Manual states 25:1 ratio on tank, along oil in reservoir. But that setting will produce way more smoke along plug fouling.

Happy Boating
 

pvanv

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Luis,

It is possible, but crazy. Double oil (20 or 25:1) is for break-in. After that, 50:1 is fine. Auto-mixing motors go much leaner (less oil, up to 120:1) at slow speeds, to reduce smoke and fouling. Is your tank bad? Otherwise why would you even consider pre-mixing on an automix motor? The pumps are amazingly reliable. I have never changed one. I suppose if the pump runs completely dry for weeks on end, being a plunger type, it will suffer... but why would you do that? If you have the oil, pour it in the oil tank -- not premix it in the fuel tank. If you don't have the oil, don't run the motor.

The 70A2 did not come with auto-mixing; The 70B and newer (70C) Remote (or Power Tilt version) did, and it was optional on the tiller model; that oil system is nearly bulletproof; don't argue with perfection.
 

Sea Rider

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Paul,

Seems you got me wrong, this ia a brand out of the box M70 newer 2 st model. How can you break in this engine with just the automatic oiling. Wouldn't that be too poor oiling. Didn't say not was going to use the outomixing at all, is going to be used after break in period finishes, that means will run empty for the first 10 hours, is there an issue with it ? Manual recommends 25:1 in tank along filling small oil tank under cover.

Other issue, we're installing a brand 50 HP Everun model, it's a tiller vertsion, converting to remote. Would like to know if there's a metal plate that holds Drag Link E to steering shaft, parts manual seems to show that Drag Link is conected straight to the side eye of the steering shaft, is this correct, no metal plate whatsoever. ?

Thanks

Happy Boating
 

pvanv

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Fill the oil tank completely, and disconnect the oil input line at the oil pump to bleed off the air in the oil filter and line by gravity. Keep the oil tank completely full for best effect. Then reconnect the oil line at the pump.

Run oil in the oil tank during break-in _and_ 25:1 premix oil in a 25L fuel tank for the first 1 or 2 tanks of gas. Initially, the oiling system will not be providing oil, because of air in the lines, so your start-up mix will be the 25:1 from the gas tank.

During that initial run, the oiling system will push air out of the check valve, and start delivering oil into the carb system. If you use up the 25:1 gas by about 10 hours, you can go to 50:1 premix for the next tank of gas; by that time, the oiling system should be purged of air, and delivering oil. You will then be getting both the automatic oiling (at about 50:1 for medium speeds) _and_ the premix fuel at 50:1, so your resultant oil ratio will still be about 25:1.

After break-in, run straight gas in the fuel tank, keep the oil tank near full, and you are good to go.
 

Sea Rider

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Paul,

Thanks for the info. How much would a 3C8-849102 Drag Link E cost with assorted hardware ?

Happy Boating
 

pvanv

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If you have an M70C, the correct setup is the Drag Link H. If so, the kit, with spacers, bolts, etc, is:
3E0849050MDRAG LINK ASSY$141.91
 

pvanv

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The Drag Link E was made for the M40/50D:
3C8849102MDRAG LINK ASSY.$121.63
 

pvanv

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The hook plate is used if you have a side-mount "splashwell" steering cable (or, I suppose if you have twin tiller cables), and also when rigging a tie bar steering for twin motors. Otherwise, the Drag Link E connects directly to the steering shaft arm of the M50D2.
 

Sea Rider

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Paul,

It's a MWX Everun 50 HP tiller engine, converted to remote, have already the remote box, gear and throttle & drive cables, just need the Drag Link E Kit, is it still available, how much would that kit cost ? Yam's bar is too short, engine doesn't turn at its full range.

Happy Boating
 
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