Adjusting Shift/throttle 85hp Merc.

[bucchb]

This is my 1st Mercury, 1973 85HP. This may sound stupid, but I am trying to understand HOW to use the shift/throttle??.

I have 2 levers. Niether seem to travel fully like an old Evinrude/Johnson. With these the 2 cables are independent, except for a starter switch. You get full movement from each.

When I opened I notice that the shift travels based on Throttle movement, thru a set of cams and eccentric.

Can someone tell me how you use these controls. For example start with both in center start position and move both forward (or backward) together? Boy do I feel stupid after owning old bots for 30 years and have an engineering degree.

 

[Silvertip]

Re: Adjusting Shift/throttle 85hp Merc.

It would help if we had a picture of your control box. Are these two levers side by side, or do have one big lever and another flat lever at the top of the control box? If the levers are side-by-side, one is the shifter (forward = forward, center is neutral, and back = reverse). The other lever is throttle. Full rear = idle. Linear movement for makes the engine run faster the farther forward the lever is moved. They are normally interlocked (you should know what that means). For proper operation, throttle lever full rear (idle), then move shifter to forward or reverse from neutral. Increase throttle to whatever speed you need. You typically won't be able to pull the shifter out of forward or reverse until the throttle is returned to idle. Why? Because the engine would over rev just like your car would if you were going wide open and shifted into neutral without getting your size 12 off the gas pedal. The other type of control box has one large lever that controls both throttle and shifting. Center = neutral. Click the button and move the lever forward or backward produces an initial shift to forward or reverse. Continuing to move the lever forward or backward increases engine speed. The flat lever is simply a neutral fast idle or warm-up lever used during cold starts or for flooded engine restarts.

 

[bucchb]

Re: Adjusting Shift/throttle 85hp Merc.

This is my 1st Mercury, 1973 85HP. This may sound stupid, but I am trying to understand HOW to use the shift/throttle??.

I have 2 levers. Niether seem to travel fully like an old Evinrude/Johnson. With these the 2 cables are independent, except for a starter switch. You get full movement from each.

When I opened I notice that the shift travels based on Throttle movement, thru a set of cams and eccentric.

Can someone tell me how you use these controls. For example start with both in center start position and move both forward (or backward) together? Boy do I feel stupid after owning old bots for 30 years and have an engineering degree.

Thanks for the quick response.
The control has 2 levers, the Throttle control (screws into spline), and Shifter, smaller flat one are both on the back side.
There is a mark "Starting" on top of control. Does this correspond to where the throttle handle should be located, as well as the nuetral spot? Inside the control is a paddle switch which I assume is an interlock from starting with too much throttle?

When I push on the Shift lever there is barely any travel in the engine end

When I recieved the control, I noticed that the throttle handle could be relocated to the front of the control which is bettter for this boat. However, I did not take note of the proper orientation on the shaft.

I guess ultimately I need to know this orientation of the throttle, i.e is it fully back or straight up????, in starting position (switch in recess) and the throttle at the the "Starting" mark.

I know this is tough to explain, and really appreciate any help you can give.

 

[Silvertip]

Re: Adjusting Shift/throttle 85hp Merc.

I'm really having a tough time with this as your description still doesn't tell me what kind of box you have. As for the throttle, think about it a little If you truely have a totally separate throttle lever, it can only operate full back for idle. Full forward is wide open and anything in between is simply like the gas pedal in your car. The shift lever must do forward, neutral, and reverse. So neutral is center. It doesn't matter what orientation the control box itself is located in. Center is neutral. Forward is -- well -- forward, and reverse is reverse. I really think you have a single lever control that does both throttle and shift and the flat lever you are talking about is nothing more than a warm-up lever and controls only fast idle. That's why it only moves the linkage a little bit (they don't want you to overrev in neutral). Here are two control boxes. Which one do you have?

This is a dual lever control. One lever controls F-N-R and the other is throttle

This is a singl lever control. One lever does it all. The trigger under the top of the handle is a release that allows the lever to be moved forward (for forward) or reverse (to back up). As you continue to move the lever in either direction speed increases but is limited in reverse as you would flood the boat if you went too fast. Straight up is the start position.

 

[bucchb]

Re: Adjusting Shift/throttle 85hp Merc.

Here is the pics. You're right nothing is more frustrating than trying to visualize an "Odd-Ball" control which I am thinking this is. I am really appreciative of all the help you are trying to give me.

I measured the travel of each control and the small lever is about 1 1/2" and the large, what you would think is Throttle is actually 3".

When I measure the PHYSICAL travel need to throttle and shift I come out with 1 1/2" to throttle and 3" min, to shift.

If you look closely on the front, top, you will see an "N" for Neutral. I am starting to think the Big handle is for shifting and the smaller lever is for throttle???

 

[Silvertip]

Re: Adjusting Shift/throttle 85hp Merc.

For an engineer you are making this way to complex. You have a very standard single lever control (yes -- I know it has two levers but one doesn't count). The key to that term is that one lever (the big one) does both throttle and shift functions. The shorter flat lever is ONLY used for cold starts and clearing a flooded engine and is called the warm-up lever. If you've mucked with the controls with the short lever up you probably screwed up the controls as they are interlocked so you can't move the big lever when the little one is up. I'll do this again for you.

Put the flat shorter lever full down.
Place the long lever in the center of its travel -- it should snap into a detent in neutral. Now try to move it forward or backward. It should not move unless you squeeze the trigger under the knob at the top of the lever. If you can move the lever without squeezing that trigger, the control needs attention because that feature prevents you from accidentally bumping the control and having the boat take off on you. If the control is working as it should to this point, watch the ends of the cables at the engine while you move the big lever forward just a little. The first cable end to move is the shift cable. Remember, you need to put the engine in gear (forward or reverse) before throttle is applied. So now that you have the gearshift cable identified, make sure it's attached to the shift linkage, not the throttle linkage on the engine.

As you continue to move the big lever forward, the second or throttle cable end should begin to move which should obviously move the throttle linkage. The very same operation works when moving in reverse. RPM in reverse is limited because full throttle in reverse will swamp the boat. They even knew that in 1973.

Back to the flat lever, it is NEVER moved when the big lever in forward or reverse gear. If you can move it in that scenario the control is broken. That lever is not the throttle -- well, it is but is not used to control the speed of the boat. The big lever does that. It is a warm up lever as I explained previously. The way its used is to place the big lever in neutral. Raise the warim up lever. Squeeze the primer bulb until firm. Turn the key to start while pushing in on the key (choke) until the engine fires. Gradually lower the warm up lever to a comfortable idle and when the engine is fully warmed up, lower it completely. Again, you should not be able to move the shift/throttle lever with the warm up lever raised.

 

[bucchb]

Re: Adjusting Shift/throttle 85hp Merc.

Silvertip you're GREAT. Thank you so much. I am here in the Smokey Mtns of E.Tennessee.

If your ever here in the area let me know. I'd like to buy you a beer.

bucchb@yahoo.com

 

[Silvertip]

Re: Adjusting Shift/throttle 85hp Merc.

Dang! Just one??

 

[bucchb]

Re: Adjusting Shift/throttle 85hp Merc.

Oh, having "a beer" is an excuse to start drinking?

Anyway, Thanks again Sivertip.

I followed your instructions and I now understand this control. I made markes with a marker as to where the neutral, forward and reverse engage, and other marks for throtle travel. I installed the cables, and tried to adjust.

It seems that there is not enough travel for the shift. I suspect there is something wrong with the shifter. The cables are tight in the control, I lube'd the shift mechanism.

Basically, if I adjust the control back to engage reverse, the forward is not engaged, and visa versa. I test drove yesterday for the 1st time and everything worked perfect, EXCEPT no reverse.

Do you have any Ideas?

(PS this engine has been worked on. When I go it the controls and cables were removed. On top of the shift mount, in the engine, was a bolt welded to a washer. It looked like someone tried to add rear travel. I did not use initially and found I could get forward and not reverse. So, I figured maybe try the bolt and my measurement of F was too far. Nope same thing. This is what leads me to believe its travel in the control, or something in the lower unit, requiring more travel than normal?)

 

[Chris1956]

Re: Adjusting Shift/throttle 85hp Merc.

OK, On that motor, neutral is a positive detent. That is, the motor will click into neutral and stay there, with out any play. Any other kind of movement indicates a gearcase problem. Is it possible you have the shift cable adjusted incorrectly?

If so, disconnect the shift cable at the motor and put the control into neutral (handle at noon position). Now adjust the shift cable barrel until the shift cable end fits onto the shift arm. Now shift into forward and reverse. The shift slider should move enough to engage both gears easily.

Hope it helps. I do not know the amount of travel the shifter should cause the shift cable to have. My '77 MerControl (older that yours) was heavily used, and it still has enough travel, and I never replaced any part of it. I am now using it on a '93 engine.

 

[bucchb]

Re: Adjusting Shift/throttle 85hp Merc.

Dah, I did it again. I have been messing with it for forwad and reverse. I have used old 2 lever controls most of my years.

I never did try just adjusting to the neutral, and see if it "catches" on either end of the travel??????. I let you know. Thanks.

 

[Silvertip]

Re: Adjusting Shift/throttle 85hp Merc.

Cable adjustment is one of the most misunderstood but least complicated adjustments on a boat. The adjustment is not provided as a forward/neutral/reverse adjustment and it logically can't be because there is just one adjustment. It's sole purpose is to adjust the length of the cable between it's anchor point and its attachment point on the linkage. Neutral on the control, neutral on the engine linkage, and as pointed out, adjust the length so the attachment points line up and you are done. If it doesn't engage forward, neutral or reverse properly after that, you did it wrong, or the problems is in the box or linkage. As you found out, adjusting to far in one direction decreases throw in the other and vice versa.

 

[bucchb]

Re: Adjusting Shift/throttle 85hp Merc.

Well I set the linkage to center of neutral and to get the linkage to line up I needed to bring the peg all the way "in" to the longest setting on threaded rod.

I think this means the cable is stretched out. It goes into forward fine, and still wont go into reverse. Do you think I have this right?

 

[Chris1956]

Re: Adjusting Shift/throttle 85hp Merc.

Make sure the Lower unit is in neutral. The barrel should be near the center of the threads, whne it is adjusted to fit into the barrel holder. Neutral is a fixed point. If you have a range of motion for neutral, something is wrong.

 

[Silvertip]

Re: Adjusting Shift/throttle 85hp Merc.

You are doing something wrong. You must start with the lever on the control box in neutral and the cable disconnected at the engine. Now ensure the shift lever at the engine is also be in neutral. From this point on you do not move either the engine linkage or the control box. You bring the end of the cable up to its attachement point on the engine linkage. You now adjust the trunnion to bring the cable attachment into exact alignment with the shift linkage. Do not pull or push on anything. Connect the cable. If you still have one gear but not the other there are other problems. It's either in the control box, the cable is stretched, it's the incorrect cable, or it's the wrong control box. Why did I say wrong control box? The control box determines the amount of throw or travel of the cable. That is not adjustable and that's why control boxes are engine specific or universal to the point where adjustment is possible.

 

[bucchb]

Re: Adjusting Shift/throttle 85hp Merc.

Thanks guys. Yeah Silver tip, did exactly what you said. There is maybe 1/2" play in neutral linkage. seems normal. I checked the amount of travel in cable and amount of linkage. F and R are both 1 1/2" from center point and neutral on shift.

I then reset control to neutral, straight up and in the detent, and positioned linkage to neutral, and brought the cable to see where it lined up. Like I said, needed to crank all the way into the fixed side.

Thanks, I'll need to find a part # on control and order a new cable. This one is like 5' too long and I need to make a 20" loop.

 

[james4639]

Re: Adjusting Shift/throttle 85hp Merc.

Thanks Silvertip for the excellent explanation of this particular control. I've been fighting the same problem as the original poster.
James