anyone else run a OMC V4 90*...

[Breakwater Bouy]

I have a 1988 Procraft 1660 with a 1987 Johnson 110 V4 hung on the back that I purchased last September 2018 and have been working on the outboard since when time allowed. I know the boat and outboard was taken care, however I was doing some preventative maintenance and some much needed rewiring ect. 

 

I'm going to take her out for my first lake test since purchase this coming Saturday. I was wondering who else is running a OMC V4 90* and what can I expect performance wise out of this 110.

 

thanks!

[slonezp]

@Way2slow is the guy you need to talk to. He is the OMC guru

[Breakwater Bouy]

13 minutes ago, slonezp said:

@Way2slow is the guy you need to talk to. He is the OMC guru

Thanks! I appreciate it.

[Way2slow]

Guru, not so sure about that, but I do have a little experience with them. 

As for performance factor, that's not really a high performance motor, more like your old chevy grocery getter.  It's basically the older 135 crossflow that was detuned for low octane gas and rated at 110hp. 

5500 rpm is max for it, between 5,700 and 6,000 rpm it develops harmonics that can cause the crankshaft to break.

They are prone to ring wear and breakage it they run on cheap, low grade oils and are not kept decarbed.  That should have been a standard routine about every 50 hours for the older motors before the days of the synthetics.

Now, don't let those couple of comments scare you, there are umpteen thousands of those motors still running great with only minor, routine maintenance through the years.

Just make sure you put a little (actually a lot) of extra gas in the tank, you're going to be surprised how fast that motor can go though it', and being new to you, you are going to be running a lot until the new to you wears off.  They put GT decals on some of them for a reason, to let you know it's Gas Thirsty.

[Breakwater Bouy]

21 hours ago, Way2slow said:

Guru, not so sure about that, but I do have a little experience with them. 

As for performance factor, that's not really a high performance motor, more like your old chevy grocery getter. I have had several of those so called grocery getters and have enjoyed them all. It's basically the older 135 crossflow that was detuned for low octane gas and rated at 110hp. I have read that online some where, however why would OMC do this? I assume to present to the public a more lower price outboard that the general public could afford in this HP 

5500 rpm is max for it, between 5,700 and 6,000 rpm it develops harmonics that can cause the crankshaft to break. I have had this harmonics issue on several hot rods I have built over the years, pushing the engines I built beyond the max..I was stupid in those days...

They are prone to ring wear and breakage it they run on cheap, low grade oils and are not kept decarbed. I do understanding decarbing and what issues it will cause. I do need to research online how this procedure is done . That should have been a standard routine about every 50 hours for the older motors before the days of the synthetics.

Now, don't let those couple of comments scare you, I wont, however taking her out for my first time will be a little nerve racking just because I don't know what to expect, but I do feel confident that I have done everything possible to this outboard to ensure a successful first lake test... but you never know what will happen...keeping my fingers crossed there are umpteen thousands of those motors still running great with only minor, routine maintenance through the years. I have read good reviews on these old OMCs, however old things do break and that is to be expected and knowing how much to invest or not invest into a broken down outboard

Just make sure you put a little (actually a lot) of extra gas in the tank, you're going to be surprised how fast that motor can go though it',I thought so, with the larger carbs and and not electronics.. she is going to do what's she's designed to do.. start, run, dring gas, get you back to the ramp  and being new to you, you are going to be running a lot until the new to you wears off.  They put GT decals on some of them for a reason, to let you know it's Gas Thirsty.I thought that the GT meant Grand Touring JK, but I like your definition better:)

 I appreciate you taking the time to give me some in site on an outboard that I never had before. I still may have some continuing questions as issues may pop up.

 

[Breakwater Bouy]

How do I properly decarb the engine and what product really work for this? 

 

How do I bump the HP back up to the 135? ...( my thoughts --adding higher compression heads from another OMC and different carbs?)

 

thanks