Another outboard mounting question.

[jaurora]

Well I purchased a newer boat without the motor which needed a little work, well anyway it is motor time. The transome on the boat has 4 bolts that were left from the previous 115HP mercury the owner had on it. I current have a 1991 Evinrude 150 on the way which should be here sometime next week.

Now the questions, I am not sure what year the mercury motor was. I have my old 1977 70HP evinrude on the back of my old boat. I was wondering if in the meantime would I be able to bolt up the 70HP evinrude to get the mounting locations for when the 150HP 1991 evinrude comes in I can just hang it and tighen it on? Are the patterns the same on a 1977 70HP evinrude and a 1991 150HP evinrude the same?

It would be nice if the mounting holes from the origional merc were the same but I do not have a way of finding out what year it was.

Sorry for all the cnfusion as I am trying to type what I am thinking and it is easier to say then to type it out.

Thank you,
J

 

[steelespike]

Re: Another outboard mounting question.

I'm just guessing But I would say not even close.Obviously the 150 is more than double the power.I think you will find the mounting bracket is massive copmpared to the 70.The 150 is about 400 lbs the 70 about 230 only about 40 lbs more than a 50hp.You will no doubt have to plug the old holes and start over.
By the way what is the boat rated for?

 

[bassboy1]

Re: Another outboard mounting question.

If you only have a week, I wouldn't screw with attaching the 70, and futzing around to get it to work. Just wait, and put the 150 on.

 

[jaurora]

Re: Another outboard mounting question.

Souns like a plan. I just dident know if there was that much of a difference between the 2.

As for the boat being rated, I am not 100% positive as there is no plate on the boat when I bought it. The boat is a 1987 19' center console sea pro. I do not think a 150 will be an issue as far as the size of the boat goes. I do not know why there is no plate on it. I think I read somewhere that it was rated for a 175 max H.P.

 

[Chris1956]

Re: Another outboard mounting question.

Probably the 150HP motor will be OK on that boat. As for the mounting holes, some time ago OB manufacturers standardized the hole pattern. If the merc and the Evinrudes have this standard pattern, they will all interchange without any drilling. One hint. If the merc has the PTT outboard of the transom clamps it is likely the old- non standard bolt pattern.

BTW - it is likely the 70 and 150 'Rudes share a transom clamp, if they are close in years.

 

[Dhadley]

Re: Another outboard mounting question.

The mounting on the 2 OMC motors are the same. It may be the same on the Merc, depending on how old it is. NMMA adopted the OMC bolt pattern as the standard "back in the day".

 

[jaurora]

Re: Another outboard mounting question.

I guess what I will do is measure the current bolt pattern on my 70HP and measure it against the current bolts hainging off of the transome. The way my luck is it will not match up because that would be just to easy but I will keep my fingers crossed. Thanks for the info always help on this great website.

 

[jaurora]

Re: Another outboard mounting question.

One more quick question, on my 77 70HP rude I have the Red plug that runs to the key switch. Does the 91 rude have the same interface?

thanks