Throttle linkage / geometry
07-13-2020 | 10:47 AM
#14
Were doomed!
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From: Chicago, IL
The only way your going to get a full sweep of the throttle sticks at the dash to correspond with the carb is to make yourself a custom arm to attach to the carb and extend it out farther away from the pivot point of the throttle linkage on the carb. Ive never had a boat that had full range of motion in the sticks the same as the carbs range of opening...
You would have to do some math but lets say you have the morse cable and it has a 3" travel....then you would need an arm mounted to the carb thats 2.125" from the pivot point on the carb for it to have the same sweep assuming the carb is opening a true 90*
You would have to do some math but lets say you have the morse cable and it has a 3" travel....then you would need an arm mounted to the carb thats 2.125" from the pivot point on the carb for it to have the same sweep assuming the carb is opening a true 90*
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-Wally
Money can't buy happiness, but it can buy horsepower. And I've never seen a sad person hauling a$$!
07-13-2020 | 12:57 PM
#15
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From: On A Dirt Floor
Draw it on paper. Shorter and longer arm below pivot point. And put shifter top in diff positions.
07-13-2020 | 02:02 PM
#16
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Sorry, had a senior moment. You want less throw. You have to raise value end higher on carb. You should be able to take a piece of longer piece of metal and bolt it to the existing arm. Than drill a hole higher up/ away from carb pivot point.
07-13-2020 | 02:16 PM
#17
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I Think I see where I was going astray. I was going with a longer lever at the carb but I was also going somewhat forward.... Ill do it again but go straight up & keep the closed throttle "cable" position "anchor point" the same so as to defeat the range of motion..?...
07-13-2020 | 02:25 PM
#18
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From: On A Dirt Floor
I've run into this and its not just a slight offset. The carb will stop the sticks from moving while there is still a couple inches of travel left even when the cable is attached at the furthest hole on the bracket. In my situation it's at least 1/4 if not 1/3 of the overall throw length. Not only does it not feel or look right when you're using it but from a reliability and breakage standpoint you have now made the throttle shaft the stop point but you can keep applying pressure to it with the stick. No doubt that's going to wear out the shafts/ seals. In my case I used 3 carbs- a Holley 4150, a Pro Systems 4150 and a Quick Fuel marine 4500. The 4500 had this problem.
Lolololol sounds like an old girlfriend.
07-13-2020 | 02:31 PM
#19
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From: Omaha/LOTO
You should also get a longer carb stud to connect the cable so it is more in line
Parts 29-34 https://www.mercruiserparts.com/bam/...y/31327/2450/8
Parts 29-34 https://www.mercruiserparts.com/bam/...y/31327/2450/8
07-13-2020 | 02:31 PM
#20
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From: Western N.Y.
Ok. The carb is at full throttle. The throttle stick is at full throttle. The lever/ arm on the carb throttle shaft needs to be extended to where the throttle cable end is in order for the carb and the stick to be at full throttle at the same time. I'd call the carb manufacturer and see if they have something. My 4150 was perfect, this didn't happen to me until I switched to the 4500. I fixed it by not using the boat anymore. 1 Maiden America posted the type of fix needed but it's for a Sniper system and I would rather have the correct lever not the bolt on fix personally.
Last edited by bck; 07-13-2020 at 02:41 PM.
