Repower - Evinrude 120 to 150

[bgiles]

Hi there, I am looking into repowering my Checkmate. I currently have a 1993 Evinrude 120, model E120 TLET and have come across a 1993 Evinrude 150.<br /><br />My question is respect to the Control Box, Oil injection (VRO) and the associated wiring. Will the existing Control Box, Oil Injection system and wiring be compatible with the higher horsepower engine. I'm thinking it may be a relatively simple swap because of the similar year or am I dreaming. I realize once you get into the newer engines that new control boxes and ignition etc. would be required.<br /><br />Thanks in Advance<br /><br />In search of more speed !!!

 

[Dhadley]

Re: Repower - Evinrude 120 to 150

Its a direct swap. It couldnt be simpler. <br /><br />Im really resisting the temptation to say something about bigger wires for the increase in horsepower....

 

[Terry H]

Re: Repower - Evinrude 120 to 150

You gonna like that swap...

 

[bgiles]

Re: Repower - Evinrude 120 to 150

Thanks Dhadley, coming from you is Gospel !!, I saw it via the web so I'll have to go and have a look at it in person and ask a few questions. It is a marina so we should be able to start it up and at least check the compression etc.<br /><br />Thanks Again for the confirmation !!<br /><br /><br />Bruce

 

[walleyehed]

Re: Repower - Evinrude 120 to 150

Whats ya gonna do wit dat dar 120????????

 

[bgiles]

Re: Repower - Evinrude 120 to 150

Hi Kenny, I called the marina today and it's already sold. However, after fooling around with the Theoretical Maximum Speed equation, the 150 would not of really increased my top end speed. Again, using theoretical numbers, the 150 has a wot rpm of 5500 with a 2.25 gear ratio compared to my 120 which according to my tach is very close to 6000 trimmed out with a 2.0 gear ratio.<br /><br />My current setup is 13 1/2 x 22 Raker running at let's say 5800/5900 rpm with a gps speed of 53 mph. If I want to gain some more speed maybe a jackplate may boost it a mph or two but that's it.

 

[Dhadley]

Re: Repower - Evinrude 120 to 150

Are you sure thats the gear ratio? If so, it may not be the recreational V6 lower unit. <br /><br />And you really want to set that motor up closer to 6000 for max performance and life. Just like your V4.

 

[walleyehed]

Re: Repower - Evinrude 120 to 150

The gear ratio of the engine in question should be 1.86:1, and the theory of pitch is just that...theory.<br />Lay a 14-1/2X22 next to the V4's 13-1/2X22, and take a better look. Efficiency is what we are looking for-less slip, and in this case, thats what you would have with the larger blade area of the V6 prop.<br />The V6 would also change C.G. some, and may have allowed more lift (Bow), equating to higher speeds with less boat in the water.<br />Apples to apples, let's compare .......Your Max on the 120 is "recommended" at 5500 too, but you're turning 6k, that's good, but you should also be turning the 150 in the 6k range as well.<br />Compare those numbers, but let's use the 14-1/2X22 Raker we'll have installed for comparison, then check on the numbers with the 14-1/2X24 that will actually bring the R's into the 5800-6000 range.

 

[bgiles]

Re: Repower - Evinrude 120 to 150

Hi Guys, the numbers that I'm throwing out there came from my Seloc 1992-1996 Repair Manual.<br />It suggest's the following, sounds like the information is a little bit off.<br /><br />1993 120 HP WOT RPM 5000-6000<br /> Gear Ratio 13:26<br /><br />1993 150 HP WOT RPM 4500-5500<br /> GEAR Ratio 12:27<br /><br />Another interesting specification according to the Seloc Book is that the Bore and Stroke of both the 1993 120 and 140 is the same as the 185,200 and 225.<br /><br />Bore= 3.685<br />Stroke 2.858<br /><br />From what I have gathered it wouldn't be the first time that the "other" manuals have provided perhaps incorrect information.<br /><br />It's quite evident that there's a lot of IF'S and BUT'S that go into fine tuning one's setup.<br /><br /><br />Again, Thanks for the feedback<br /><br />Bruce

 

[Dhadley]

Re: Repower - Evinrude 120 to 150

Yes, lots of V4, V6 and V8 loopers have the same bore and stroke. Some are different. At least Seloc got something close.<br /><br />I think you'd enjoy the difference. While its true the V4 is a torque monster the 60 degree 150 makes great torque too and revs real quick. And the weight difference is almost nil. 5 lbs between the two 20" models.

 

[walleyehed]

Re: Repower - Evinrude 120 to 150

It's (the 120) a looper at 3.685, in 90 deg....for what it's worth. The "Big-Block" V4.<br />The 1993 150 has a bore of 3.600, specific to 150's '91-2000 (60 deg loopers)and the 175's of the same vintage...they don't use the same pistons as the 120-140 Big blocks.<br />Yes, run both engines at 6000RPM if possible.<br />p.s. Dhadley will correct my mistakes if I'm wrong.....