1987 Mercury Force not reving. NEED INPUT!

[dbernstein7]

Hi! So I just bought a 1987 bayliner with a 1987 85hp Mercury Force outboard engine. It starts right up and sounds good in idle. When I push the throttle into gear, the prop starts to spin, but when I push the throttle down, the engine sounds the same as it does in idle, and the prop moves at the same speed. This happens when the throttle is completely opened up. I wasn't using the right size Muff so I don't know if enough water was going into the intake. Could this be the problem? Anything helps. Thanks!

 

[Silvertip]

The engine would rev with NO water but don't do that unless you want to buy another one. Did you have the shift and throttle cable disconnected at the engine for any reason and perhaps have them swapped? Have someone operate the throttle/shift lever while you look at the engine end. As the throttle lever first moves, the shift cable operates the SHIFT lever. As the throttle lever moves more forward the carb linkage should begin moving. If not, either the throttle cable is broken, disconnected at either end, or the shift/throttle box is broken.

 

[dbernstein7]

I took it as is. I checked yesterday and had someone operate the throttle while I looked. I didn't get a close look, but there was definitely something moving. Could have just been the shift lever because when initially put into gear, the prop started to spin, but would not move any faster when I pushed down on the throttle down. I'll check again today to look at the throttle lever on the engine end.

If it is just the throttle cable, is that a big/expensive fix?

 

[The Force power]

lets find out if it's the cable or something else first;

With the Cowl removed, have someone move the throttle ONLY on the controls & see if the Cable-end + linkage that's connected to the carburetors move.
If the Cable-end moves inside the Cowl; then look towards the attachments/linkage why they don't move.
If the linkage does move and the Carburetors do open; let us know

 

[dbernstein7]

Will do. I'll get back tonight after I test.

 

[dbernstein7]

So if figured it out. Cables and everything are fine. But throttle handle, however, goes further down than I thought. Once I give It a little more pressure (more than a throttle should) It opens right up, full power. I think if I replace the throttle handle itself it’ll feel good as new. What do you guys think? For now though, I can get the boat up to full speed if I give the throttle a little extra push.

 

[roscoe]

Welcome to iboats.

It is normal for the handle to move a couple inches as the motor goes into gear.
It will move a few more inches with no increase in engine speed.
Then it will move forward another 5-6 inches as the throttle opens up.

Also, handle does require quite a bit of pressure to move it, or you would have to keep your hand on it at all times to maintain a speed.

Lastly, your '87 Force was made by US Marine, not Mercury.

 

[jerryjerry05]

If the handle's loose? there's a set screw on the bottom of the handle.

Don't shift unless the motors running or you have someone spin the prop.
It can bind the cable and break something.

 

[dbernstein7]

Thank you all for the help!

 

[VivaLaMigra]

Correct me if I'm wrong but on a nineteen EIGHTY-SEVEN Force 85 it wouldn't be possible to accidentally switch the throttle and shift cables as the distance from the anchor point to the throttle or shift lever is different; that's why the CONNECTORS are different lengths - short connector on shift and longer, spring-loaded one on throttle. The '87 models still had the Chrysler style linkage with the Morse cables, right? Or have I lost it? Anyway, I don't think swapped cables COULD be the problem but sloppy cables or a worn control box - even Bayliner used multiple boxes either HiLex or Morse INCOM - could be.