Force 125 - Can you rev up in Neutral?

notop

Seaman Apprentice
Joined
Feb 24, 2011
Messages
37
I have just acquired a 1986 Bayliner Capri with a Force 125 outboard (model 1254X6B, serial# 1800). Shift Controls are by US Marine.

Supposedly, pulling the shift lever out (ie, away from the sidewall) allows you to move the lever forward/reverse without engaging forward or reverse gear -- the engine is supposed to stay in neutral. On previous boats I have had experience with, you would do this to rev the engine to speed up warm-up time or just check that the engine was revving correctly.

Now, although I know the engine runs, I haven't actually done so as I'm waiting for a new impeller, but just testing the shift lever with the engine off, it seems to me that the "Tower Shaft Tab" is limited by the "Shift Arm Tab" (to use the Owner's manual terminology) so that you cannot rev up in neutral. Well, OK, there is a **small** amount of play between the Tower Shaft and Shigft Arm tabs, but I doubt you would get more than 50 RPM higher revs before the two come together.

So my question is: How do you rev the engine in neutral??? The Force 85/125 Owner's Manual that I have talks about aligning the two tabs vertically, but does not mention any horizontal alignment. Is there supposed to be a gap between the two tabs so that you can rev up at least partially in neutral (I imagine you don't want to go WOT with an unloaded engine, but surely you should be able to bring it up to about 2500 without damage). I have obtained the Clymer version of the Repair manual for this engine and it does not even mention the Tower/Shift tabs (unless I missed it somewhere).

Any clarification you can give me will be appreciated.
 

Frank Acampora

Supreme Mariner
Joined
Jan 19, 2007
Messages
12,004
Re: Force 125 - Can you rev up in Neutral?

Believe it or not, that small amount of clearance between the two tabs is more than sufficient. In a correctly synchronized engine the throttle will crack open and timing will advance about a couple of degrees. (see the FAQ sticky at the top of the page) This will allow the engine to rev to somewhere between 1500 and 2000 or so RPM.
 

notop

Seaman Apprentice
Joined
Feb 24, 2011
Messages
37
Re: Force 125 - Can you rev up in Neutral?

Believe it or not, that small amount of clearance between the two tabs is more than sufficient. In a correctly synchronized engine the throttle will crack open and timing will advance about a couple of degrees. (see the FAQ sticky at the top of the page) This will allow the engine to rev to somewhere between 1500 and 2000 or so RPM.

Ahhh, so! Thank you for this information. Upon further examination, I noted the following:

1) The gap that I have between tabs is maybe 1/16".
2) The Shift Tower tab appears to be stamped/forged and has some flash around the middle. I think I can probably trim the flash with an Exacto knife or points file.
3) (and it's a biggie) With the aid of a helper, I was able to see that the clamp holding the throttle cable on the engine end was loose. It looked tight, but when I put the screw-driver to it it needed another turn and a half before it became tight.

I'll be installing the new impeller (arrived yesterday) sometime in the next few days when the weather is a bit more cooperative, and then I should be able to fire 'er up. Clearly, I need to do a complete linkage adjustment as per your excellent directions in the above-mentioned sticky. Thanks again.
 

notop

Seaman Apprentice
Joined
Feb 24, 2011
Messages
37
Re: Force 125 - Can you rev up in Neutral?

Just a follow up:

Replaced the impeller yesterday, following the instructions in the FAQ sticky. Good thing too or I would not have known about the hidden seventh bolt holding the gearcasing on. It was missing on my engine, but a quick trip to the hardware store fixed that.

After carefully filing off the afore-mentioned flash, I did the throttle linkage adjustment as best I could... boat wasn't in the water so I still need to set idle RPM in forward gear, but overall I think it went pretty well. Idle in neutral is about 900 (sitting on the trailer with watrer-muffs on) and fast idle is about 2200 - right where I want it. Shifting seems nice and smooth with no clunks or grinds. As Frank mentioned, I have about 1/8" gap between the shift tabs, so that is further proof I must have done something right.

One last thing... as I mentioned in previous post, the biggest problem was that the throttle cable clamp was loose. I've tightened it and have also gone over every other screw and bolt on that engine. The head bolts were all tight, but I was surprised at how many others, especially the screws, were not. I guess it's something to keep an eye out for.

Cheers, everyone!
 
Top