1985 85hp Force

[gdfnsaf]

I just bought a 1985 85hp force at a garage sale. It was on the water this spring i was told.When i went to change the llower unit lube I noticed a hole on the underside that looks like somethng had been bolted there. I googled the motor and found that there should be a spout there that comes down behind the prop. Can anyone tell me if the motor is ok to run without this piece there? It is the part that is circled in the picture.

Thanks
Larry

 

[jerryjerry05]

Re: 1985 85hp Force

That is an exhaust snout.You can run it like that but will have trouble venting exhaust at lower speeds.It shouldn;t run as good.Jerry

 

[john from md]

Re: 1985 85hp Force

The 85 Force engine has exhaust relief holes on the back of the leg for idle operation. The only thing that not having the snout on will affect is your trim. The snout on an 85hp engine is also the trim fin. Without it, you can't adjust for prop effect and will have a handfull holding it straight at high speeds. It will also make really fast right turns at high speed so plan accordingly.

John

 

[dan1979]

Re: 1985 85hp Force

I am missing the same piece on my 86 50HP, there is an exhaust hole on the back just below the cover though. Will this cause some performance problems? Seems like I can't the boat up to speed. (No spun prop or anything like that, its on a 16' Vhull fiberglass boat)

 

[john from md]

Re: 1985 85hp Force

If you are refering to the snout, you should not see any performance problems other than that of trimming out prop forces. When you say can't get up to speed, what to you mean? Are you refering to a speed off of the speedometer, do you mean planing, or do you mean rpm?

Please be a bit more specific on what you are not achieving and why you have come to that assumption.

Regards,

John

 

[gdfnsaf]

Re: 1985 85hp Force

Thanks guys for the information. I thought that it was probably an exhaust port from the way it looks. My thought was that if it was exhaust, that it might cause some cavitation problems with the exhaust blowing into the path of the prop. Thanks again for the info


Larry

 

[dan1979]

Re: 1985 85hp Force

According to my Fish Finder speed-o I am only getting about 12mph out of my outboard. I was told by several marine shops that I should be able to hit at least 20mph with a 50hp. The motor sounds firm when I have wide open but just can't get it any more speed out of it. It feel like I am not getting up on plane. Bow looks pretty level when wide open.

Is a 50HP enough for my boat? Its a 16' FB V-hull. I was told a while back that force measures their HP at the fly, so its probably 36hp at the prop. Is this true?

 

[john from md]

Re: 1985 85hp Force

Depending on the year of manufacture, HP was taken from the flywheel earlier and then from the shaft. I believe the transition period was around 1985.

I don't know how heavy your boat is but my 16foot Bayliner is 1275 and my 85hp Force is 255 and I can get 40 mph.

Is your cavitation plate level with the bottom of the boat? If it has a short shaft, that could be your problem. If your cav plate is even with the bottom, try moving the engine out one hole and see if that helps.

Do you have a Fin installed on your engine?

Regards,

John

 

[dan1979]

Re: 1985 85hp Force

John,

The year of the motor is 1986, so hopefully I did catch the transition and its 50HP at the shaft. Do you know if there is a way to tell this, maybe something marked on the motor?

I attached a photo of the plate level to the hull. I am sitting about 1" above the hull. I think part of my problem (hopefully) is that at first was that I running the motor at full tilt, furthest away from the transform. When I took it to a prop shop to see it the hub was spun they told to me run the motor as close to hull as possible. I hope that works.. I'd really hate to find out that my motor is to damn small..

All I want is 20 - 25mph, just enough to get from one fishing hole to the other... 12mph is painful!

Thanks,

Dan

 

[john from md]

Re: 1985 85hp Force

Dan,

You are losing some efficiency with the cav plate being above the level of the bottom of the boat.

The best setup for an outboard is for the prop to be pushing straight back. This usually occurs when the tilt is set at the minumum on your plate. However, due to loading and individual boat characteristics, you may have to bring it out a hole or two.

Start at the minimum and try it and work out and see what works better for you.

Regards,

John

 

[dan1979]

Re: 1985 85hp Force

John, hey thank for all your help. I plan on taking the boat out tomorrow evening just to run a test. Hopefully I can get some more speed out of it.

Thanks,

Dan