repowering boat (transom holes and omc motor questions)

[fishdog4449]

I am considering repowering my Glassmaster due to the reliability issues I've been having with my '80 mercury80 . However, If i decide to buy a used omc, will the transom bolt pattern match the merc? I will be shopping for a '80-'95 carbed evinrude/johnson 70-115hp (boat is rated to 135, but scoots at 40mph with the 80). I really like the look of the johnyrude v-4s and have heard good things about reliability and power, but never ran one myself so any feedback from you guys on these motors?

 

[tashasdaddy]

Re: repowering boat (transom holes and omc motor questions)

i like the v 4s far better than the merc. it really depends on the year of your current motor. they finally got it together with transom mounts. but don't count on them matching. 3m5200 is a great filler for existing holes. and just redrill.

 

[fishdog4449]

Re: repowering boat (transom holes and omc motor questions)

thanks tashasdaddy . I will try to find a motor with same mounting patter, I'm just reluctant to drill more holes in transom but might have to if it comes to that,.

 

[fishdog4449]

Re: repowering boat (transom holes and omc motor questions)

found an 1986 90hp johnson v4

 

[tashasdaddy]

Re: repowering boat (transom holes and omc motor questions)

very good motor.
BUYING A USE MOTOR

overall condition, condition of the place you are buying it from, usually tells you how they care for things. compression 100 + psi, and within 10% of each other, good strong blue spark, no water in the lower unit oil. look for discolored paint, (sign of over heat at
one time, also scarred up bolts, as why. have them start it. if they fail to put it in a barrell or tank, or on muffs, or in the water, to start it they don't know what they are doing. best yet is to take it for a 30 min to 1 hour test run. also if remote controlled motor, the controls should come with it.

 

[fishdog4449]

Re: repowering boat (transom holes and omc motor questions)

thanks will keep this in mind!

 

[fishdog4449]

Re: repowering boat (transom holes and omc motor questions)

well previous motor sold, but my friend says he has a '72 100hp in good condition that I can get for cheap. this is a little older than i planned to go, but he says its in great condition. any known issues with this particular motor?

 

[crb478]

Re: repowering boat (transom holes and omc motor questions)

It is one of the electric shift models and will be very expensive to repair if it breaks and if you can find parts. I would probably avoid this model.

 

[gss036]

Re: repowering boat (transom holes and omc motor questions)

I think most all the mounting holes are about standardized now. I just had a Honda 225 HP installed to replace a 1989 Merc 200hp and holes matched after 19 years.

 

[fishdog4449]

Re: repowering boat (transom holes and omc motor questions)

well maybe its not a 72..the 72s were dark green on the lower and a white cowl right...
is this a repaint job or did they really make a blue evinrude at one point...
either way its in great condition. i haven't checked compression yet gonna go look at it this weekend

I don't have the model # or serial # I will get those this weekend and determine what year it is.

 

[crb478]

Re: repowering boat (transom holes and omc motor questions)

It looks like a 72 or earlier from the picture. If it is cheap enough you may want to consider using it until something breaks that is too expensive to fix. I would verify the comperssion and spark and make sure that it shifts well before I invested in it. It looks clean and my have many years left in it. It would not be my first choice of engines to use, but it does appear to have been well taken care of.

 

[fishdog4449]

Re: repowering boat (transom holes and omc motor questions)

my thoughts exactly. when I look at it this weekend I will inspect compression etc. he told me he rebuilt ignition system a few years ago.

 

[tashasdaddy]

Re: repowering boat (transom holes and omc motor questions)

if it only has one throttle cable and the wiring harness, it is an hydro-electric shift. the control has to come with it. the solenoids, in the lower, that shift the gears, are no longer available.

 

[fishdog4449]

Re: repowering boat (transom holes and omc motor questions)

ok. i will keep yall posted if I look at it this weekend. also, I have a 1974 merc 115 inline 6 that is in great condition, ive done some work on it and it runs great good compression but didn't have working controls. I bought some on ebay the other day so now putting this motor on is an option as well. how would this compare to the merc80 i have now or the previously discussed evinrude as far as fuel economy, power,etc?

 

[The-Machinist]

Re: repowering boat (transom holes and omc motor questions)

That old inline six will drink like a sailor on shore leave
Other than that, they are quite smooth, well built motors. If taken proper care of it will quite possibly outlast you and me.

 

[fishdog4449]

Re: repowering boat (transom holes and omc motor questions)

so the 11-12 gph at wot is not unrealistic it seems. well what i am hoping is right now i have a merc 80 on the boat, and i think i will be able to run the 115 at lower rpms and hopefully not increase gas usage that much