Merc 1150 throttle

[MatthewtheDruid]

Is this normal? When I push the shifter back the throttle moves immediately, as expected, from closed to fully open. Using the idle lever or moving the control to forward, it shifts fine but doesn’t appear to move the throttle cable until I’m over halfway forward, it opens 100% as well. Seems odd, don’t see anything out of place in the forward controls and I’m thrown Off by reverse being perfectly but forward being different.

thanks

 

[jimmbo]

Which control box?

The MerControl used from the mid 70s till about 1978 was not very lineer, the throttle didn’t do much until the last couple inches of movement, then all the action happened very quickly. I never paid any attention to how it worked for reverse.
The idle lever is only for speeding up the engine? It should not be shifting it

 

[racerone]

Well, ---The shifter cable is the first one to move.----Are the cables switched by any chance ?

 

[MatthewtheDruid]

I was tired so I may have worded it poorly. Shift works instantly and perfectly. Both directions. Throttle response and range in reverse, perfect and quickly engages.
I had to adjust the cable
to get it to open up fully when using the idle lever or forward gear. Still takes a substantially distance before it throttle response(watching the mechanical movements)
shifts right away both ways.

Anyway, Jimmbo it’s exactly as you describe. 70% of the range it’s shifted, no throttle, then 0-100 in that last bit. I’m assuming it’s a 74, the year of the engine. Thanks

 

[jimmbo]

That is the control I was referring to(previous post should have been ‘early 60s till about 78) However, you only adjust the cable length to provide a bit of preload against the idle speed stop, no so you can attain WOT with the fast idle lever. If the shift cable is misadjusted, control lever in neutral but shift cam in gearcase not in the neutral detent, will make for one gear to engage with less main lever movement than the other

 

[MatthewtheDruid]

I wasn’t getting wot at first in forward, after adjustment I am getting full range on the throttle plates. The challenge is constantly sorting out what normal is. It seemed like I should have a nice smooth throttle response on the full range of th levers. It sounds like I can stop trying to “fix” this and move on to the flooding carbs. (Bad floats, easy fix)
thanks

 

[jimmbo]

The linkage on the engine, is actually quite simple in operation. Initially as the throttle lever is moved the timing advances while the carbs remain closed. At what is called the primary pickup point, the carbs open very slightly. further movement of the throttle results mostly in more timing advance. Once maximum timing has been reached, further throttle lever movement now opens the carbs.