old (unsure of year) Honda BF75 (7.5hp) outboard won't throttle in neutral or reverse

[acarleson]

Hello,
I have an old Honda BF75 (7.5hp) Honda Outboard. It starts up great, run great, shift great, but will not rev up at all (throttle seems locked) when in neutral or in reverse.

Is there something I'm doing wrong here, or is this normal? Any suggestions on what I should be looking for as far as a fix would be very appreciated.

Thank you!

 

[tpenfield]

Many/if not most small engines have a governor that prevents advancing the throttle very much when in neutral. Nothing good can happen over revving an engine.

Pull the cowl and check to see if that is the case.

 

[flashback]

I have one of those on a sailboat. it will not rev high in neutral or reverse. If you look at the linkage under the cowl you will see how it locks out.

 

[Alumarine]

When in Neutral or Reverse the throttle grip movement is restricted in how far it can move.
When the throttle cable is adjusted properly the maximum rev's in Neutral are 5200 rpm and in Reverse 3200 rpm, depending on year.

 

[acarleson]

Thank you for all the replies. Can I just double-check one thing? Based on your replies, it sounds like (but I could be misinterpreting here) that I should be able to rev just a little in neutral and a little less in reverse. Mine can not rev AT ALL. The throttle does not move even a millimeter in either neutral or reverse. The reason I figured this is a problem is because my boat can move backwards in reverse, but very, very slowly, and if there's even a slight breeze or current, the reverse isn't strong enough. I totally get limiting revs but it seems odd to not be able to rev at all in reverse, to the point that reverse doesn't do anything? I'm using this on a 12' aluminum dinghy, so even being able to rev a tiny amount should be enough, I would think. To give some perspective, my throttle has "start" and "shift" listed on it, and when I start it, it's in neutral at the "start" position, and I can't even get it to throttle up to the "shift" section when shifting out of neutral.

Is there any way to adjust the governor to give me just a little play in the reverse/neutral?

actually, I thought of another thing, if anyone happens to know the answer off the top of their head: my shifter seems to have two notches for "neutral." There's a forward gear, and a reverse gear, and in between, there's a neutral zone. I can feel two pretty positive notches in the neutral zone, and both seem to be neutral, so I'm not sure why there are two stops in there.

Thank you!!

 

[Alumarine]

The start position of the throttle lever should provide more rev's than the shift position.
Check the Throttle Friction Knob at the end of the throttle lever.
It may be too tight and stopping movement.
If that's not the problem you will have to look and see what is causing the issue.
I don't have access to my motor to check.

Here's a link to manual that might be for your model.

https://cdn.powerequipment.honda.com/marine/pdf/manuals/31882621.pdf

 

[flashback]

Most likely you need to adjust the cable. as far as I know that is the only intended adjustment. The shift lever has a metal plate on it that prevents the throttle linkage from moving much unless it is in forward position. I suppose you could remove that plate or maybe mod it..

 

[km1125]

Look at the shift linkage and where the throttle linkage interacts with it. On my BF8, it is right in the front of the motor. You can see how the plate on the shift linkage moves out of the way of the throttle linkage so they throttle can open up fully in FWD, but blocks it partially in both Neutral and Reverse. You might just have to adjust the shift linkage for everything to work correctly.

 

[acarleson]

Hi, yes, I looked at it today. There is that little plate that blocks throttle movement when in neutral/reverse. On mine, when in neutral/reverse, the plate is completely up against the throttle control so there is zero play. I guess I can't figure out how to get any extra play? In neutral it's no big deal but I would really like my reverse to work. What do I need to adjust in order to get it to work? Thank you

 

[km1125]

Put the engine in reverse. Loosen the carb linkage adjustment Loosen the shift cable by loosening the two nuts then move them close to the left in the pic, which will loosen the cable. You should be able to then move the throttle A LITTLE BIT. If it's too loose, then tighten the adjustment a bit. Then adjust the carb linkage adjustment so that the carb throttle closes all the way when the throttle handle is at idle and opens all the way when the throttle handle is at max and the engine is in FWD. Tighten everything down and you should be done.

 

[acarleson]

hi @km1125 I have adjusted my cable as you suggested but I have zero play. I backed both of the nuts all the way back and the cable is as far left as it can go (also tried as far right as it would go) and each time the plate completely blocks off the throttle from moving. Is it supposed to move a little, or is it not supposed to move at all? What is the rationale behind completely stopping any throttle in reverse? Kind of seems like a little throttle (even half throttle) in reverse would be helpful... thank you

 

[flashback]

You may have to mod the plate as recommended by honda in the service manual.

 

[acarleson]

@flashback Thank you! I had no idea that the manual suggested this, I'll definitely mod the plate. I was a little worried about why Honda would have blocked it off but knowing that Honda says that you're allowed to mod it makes me 1000 times more comfortable. Thank you again

 

[km1125]

If you look at the "unmodded" side, it should allow for 3800RPM in reverse. There definitely should be the ability in neutral or rev to accelerate some, just not full throttle. That mod allows you to increase from 3800 to 4400 in reverse.

 

[acarleson]

Hm yeah I can't move my throttle at all, the linkage is jammed up against the plate... guess I should track down the root of that issue first