questions: throttle and tachometer

I have 2 questions for ye today:

1. The throttles at my upper and lower steering stations are mechanically linked to the speed controller on the engines. If I increase engine speed to, say, 1800 rpm, and then let go of the throttle, the engine speed will drop to around 1500 rpm. Is this something I can adjust-out of the linkage somewhere, or do I have to replace something to get the engine to "stick" at the speed I initially set it? The throttles are 1987 vintage Morse controls.
2. There is a little window on my tachometer near the hour meter, and this window alternates between a black window and a white window at roughly 3 second intervals. What is the purpose of this window (see pictures below):

Greetings,
Mr. sbg. #2) I suspect the object in question is simply a tell-tale to indicate the hour meter is running.
#1) Morse are good controls. Sounds like a friction device (to hold set speed) of some sort needs be tightened. Just re-read your post. It may be a cable adjustment as well which, IF I'm guessing correctly, would not be hard to do.

Your throttle controls the governor setting which is part of the engine's fuel injection pump. Find the pump and where the throttle cable terminates at a lever on the governor. Have someone move the throttle and see if the lever falls back a bit. You can do this with the engine off.

If the governor's lever falls back after the throttle is moved, that is what is causing your rpm drop and you need to see why. Maybe a spring has broken. Maybe there is a friction device, but usually trawler controls, particularly dual helm controls have plenty of friction naturally.


If the lever is not moving back, then maybe the problem is internal to the governor.


And finally, do you possibly have an electronic shift and throttle control like ZF Microcommander or Kobelt? If so something is screwy with the electronics.


David

If you push it up to 2000 will it settle at 1800?

Usually the alternating black and white on hr meters are to show 10th of an hr. At 3 seconds, each blk or wht would be a tenth.

Control levers can slip from them not being secured to fixed objects. If you have large loops in them and the are free to bounce around, they can sometimes cause a slight shift in control settings.

I'm surprised no one has given you the answer yet. Almost every control ever made has some way of adjusting the friction to prevent the exact problem you're having. If you have the typical Morse controls from that era there is a friction adjustment screw on the outside at the base of each lever. It is the screw that would seem to go directly into the center of the shaft that the lever is mounted on. tighten it until you have enough friction to keep the control where you put it. You may need to only tighten the ones at the lower station or both lower and upper for best feel. Depending on how the upper and lower throttles are linked may impact which way works best.

Ken

There are several potential causes to the throttle slippage issue and the previous posters have covered the obvious ones. The first and easiest check to make is the friction controls on the throttle quadrants, assuming your controls have these. If that's not it, then checking the other things mentioned would be in order.

As to the tachometer display, the white dial (right end) in the number display is normally the tenths of an hour display. It should advance one digit every six minutes. Whether it clicks over rapidly or gradually changes to the next number over the course of six minutes will depend on the design of the instrument.

The window that alternately shows black and white is most likely simply an operational telltale as RTF said. But then so is the movement of the white 10th of an hour wheel so I'm not sure of the reasoning behind a separate indicator unless it's simply a "because we can do it" feature on the part of the manufacturer.

If the white tenth of an hour wheel clicks from one number to the next perhaps the black and white window indicates the passage of some segment of time--- a 20th of a minute?--- during each six minute interval although why anyone would care is not something I can figure out.

oscar said:

If you push it up to 2000 will it settle at 1800?

Click to expand...

I was doing some engine testing over the weekend, and the last step in the test was to run the engine at 1800 rpm for 10 minutes. I had to go a little over 2000 to get it to settle back to 1800. I got some great feedback on my throttle question, and I'll try to look into the suggested solutions this weekend.

from beginning of black or white to the beginning of black or white again is 6 seconds (each segment pauses for 3 seconds) thus tenths of an hour.


though it is not that it is a feature I have seen used often, other than to know the hourmeter is working.