Evenrude 1955 7.5 help needed

[Dmacken]

Hello all,<br /><br />New to forum but have found many answers from reading posts already. My first boat purchase has an Evenrude 7.5 from 1955 on it. I want to fire up this motor and check it out. The starting instruction say to "turn large adjustment knob to 3" but I see now graduation marks anywhere on the coweling where this knob is located. What clock position is 3 on this knob? also what is the starting point of this knob? That is do I turn it clockwise till it stops and then counter clockwise to what ever the 3 possition is or do I turn it counter clock wise till it stops and then turn clockwise to where ever 3 is?<br /><br />Also I see what looks like the water pump inlets above the prop. How deep in a bucket/barrel does this motor need to be to draw water into the water pump? Where will the water come out so I am sure the cooling system is working?<br /><br />Is Hypoid oil anything special or can I get it at my local Pep Boys or something?<br /><br />What will my best mix be for gas oil and what products might you recomend?<br /><br />I will be calling to purchase an owners manual on Monday and hope it will give me more info too.<br /><br />Thanks for any help.<br /><br />Dave<br /><br />Any other help would be great.

 

[fishingkid]

Re: Evenrude 1955 7.5 help needed

Hi I will tell you about my 56 and 58 johnson 7.5 (suppose to be mostly the same). The water pump must be under the water line. The water pump on mine is on top of the actual lower unit assembly (Where you can see it is bolted together). There are 6 positions on mine for high and low idle (threes are dirrectly in the center). The water is drawn into the engine through a plate looking thing with holes in it next to the drain plug for the oil the holes above the prop are for the exhaust and water outlet. Which oil to run is debated all the time but it should be 24:1. Hopefully someone can confirm all this as I am new to all this also. And just trying to give you some ideas as they may be similar but different. Hope it helps James

 

[rolmops]

Re: Evenrude 1955 7.5 help needed

Hello Dave<br />The oils you are going to need for your machine are TCW-3 oil to mix with your gas at 24:1 and a 90 weight oil for outboard lower units.Something like Sierra C type lower unit oil. You can get this at Walmart.But if you are a first time buyer it is definitely a good idea to go to a marina or outboard repair place.You will pay a bit more, but you get their directions as far as what oil to get.

 

[Chinewalker]

Re: Evenrude 1955 7.5 help needed

The numbers on the knobs mean absolutely nothing as far as the instructions go. There is a set-screw in the center of the knob that loosens the knob on the shaft. The best way to get the needle valve set is to close it fully clockwise (gently - do not over tighten!). Then open the valve about 1.5 full turns. This will allow you to start the motor. Then, after motor has warmed up, adjust high speed valve with motor in gear at high speed - turning the valve inwards (clockwise). Motor will gradually increase speed as adjustment is made, to a point where it will sharply drop off in RPM. At that point, back the needle out about 1/4 turn.<br /><br />At this point idle motor down and follow same procedure for low speed needle. Motor will pick up revs as needle is turned inwards, then it will spit or sneeze when you've gone too far. Back out 1/4 turn from that point.<br /><br />Main waterpump inlets are on the leading edge of the exhaust snout, directly below the cavitation plate. I would highly recommend replacing the waterpump impeller as a matter of course. They're inexpensive and fairly easy to replace.<br /><br />- Scott