1979 85hp Johnson seahorse power tilt or keep manual assist?

[scboater90]

I have a 16ft fiberglass bass fracker with a 1979 85 ho Johnson seahorse. The motor currently has manual assist tilt, in looking to install power tilt and trim. Right now I can't get the boat to plane out, unless I move up front. What would be the best route to acquire the power tilt/trim, and to then install it? Or would I be better off leaving the motor manual, and figuring out how to get it to plane with the power t/t? This is also my fist boat, compression checks good, 17 pitch prop.

 

[emdsapmgr]

There are two good methods to improve boat planning. Power Tilt/trim is a good way to start. Secondly, changing to a lower pitch prop is another proven way to improve planning. Some difference in the cost between these two options. Usually, a boater will find it is a combination of the two that provides the best option. You may find that by adding power t/trim, you will eventually wind up changing the prop pitch anyway. My 79 85 hp Johnson came with power trim. I'd recommend getting a used tilt/trim unit and bolting it on. Must be countless hundreds of these trim used units laying in salvage yards everywhere. It works great on my 15 1/2 Bayliner Capri. I run a 17 pitch black stainless factory prop with the trim unit.

 

[titaniumneck]

Man is right, you can find discarded tilt/trim easily. And usually the brushes just need to be changed and some sandpaper and wd 40 too.

 

[racerone]

Your boat should plane out as it is now.-----So is the motor performing properly ?----Is the boat water logged ?-----Have you checked the boat ?

 

[ezmobee]

An 85 should easily plane a 16' boat. Either your boat is waterlogged and ridiculously heavy, or more likely your motor isn't firing on a cylinder. They will sound fairly normal with a dead hole but have low power.

You are fortunate that OMC changed their tilt/trim setup in '78 and it stayed the same into the 90's so finding a used TnT setup for your motor shouldn't be too terribly expensive. Used units go on ebay frequently for $200-250.

 

[scboater90]

All cylinders are firing, compression checks good. It will plane the boat, but only after putting my passenger up front. I put it on the lowest tilt setting. Once you get it in the water you however, there is no changing it. How do I tell if the boat is water logged?

 

[racerone]

Fact-----There is something wrong with the motor !-----Or there is something wrong with the boat.----------Find a shop with a test prop or a dynomometer to check power output of the motor.-----Is this a recent purchase ??

 

[scboater90]

Yes within the last week recent

 

[racerone]

I believe you should follow advice in post # 7----Perhaps you bought previous owners problems.

 

[scboater90]

I'll try that, now when the boat planes out, it'll scoot across the water at 35-40mph no problem. Let's hope I didn't buy into a problem, don't want to put to much money into a 37 year old motor.

 

[Chinewalker]

If your motor is tucked under all the way now, it ought to plane off easily. Adding trim won't change that. I concur with above - something else is going on. Your top speed sounds okay, so I suspect the motor is more or less okay. I would look into the boat. Check for saturated foam under the decks.

 

[jbcurt00]

A nearly 40yr old fiberglass boat is definitely a likely candidate for have water intrusion below decks.

Moving this to boat resto forum. They'll help you assess the boat.

Welcome to iboats

 

[Woodonglass]

I'd put my money on WaterLogged Hull! Any soft spots in the Deck/Floor?

 

[scboater90]

No soft spots on floor, I have it at a marina now, getting it diagnosed. I'm having him check motor and the boat. I'm putting my money onto the boat also.

 

[Baylinerchuck]

I agree with most here that say it should plane with the manual tilt 85 easily. I had a 16' Capri and I bought it with a 1978 85 hp manual tilt Johnson. I put my pin in the 3rd hole from the bottom. It planed well and was fast with my wife and 2 small kids. I did have trouble when I had 4 adults in the boat. I had to send 2 up front to get it on plane. This was especially the case if I was pulling a tube or wakeboard. It would plane quickly no matter the load on the last hole. I just didn't want to lose speed by dropping my pin to the bottom hole so I purchased an Atwood hydrofin and installed it. I had no more issues after that at all. The hydrofin was amazing on that motor.
Before I sold the boat I installed a 90 hp with power trim. It was like night and day. I picked up 12 more mph with that motor, and ultimately the adjustable trim. I couldn't have been happier.