Throttle linkage / geometry
 

Having an issue with throttle cable geometry. What are you Holley guys doing with your carbed engines & zero effort controls to get proper throw? I have mine set up like many Ive seen and if I set the cable & mount bracket for proper idle stop & cable length, I reach full throttle at 3/4 stick, ish. Ive tried different adaptors at the carb lever but no luck. There isnt any way to pin the cable at the throttle controls to be shorter. Only one position unless you want to reverse the throw for push instead of pull.
Any ideas?
Thanks in advance. Trying to get this 1991 Formula 292 SR1 in the water after a 4 year overhaul.

https://cimg3.ibsrv.net/gimg/www.off...6ae01541fa.jpg
https://cimg4.ibsrv.net/gimg/www.off...63697a5ee9.jpg

Without measuring now (late) i have the cable’s throttle end out about 3/4 “ ? From carb linkage. Can use longer bolt with 2 nuts instead of 1. Head of bolt carb side of linkage. Nut on other side to tighten bolt to carb’s linkage. Now you can install cable end. Use a locking nylon inserted nut turning in just enough so cable end is not bending in towards carb.

Hopefully described that well ?

edit in: i’ll try to remember to take a pic tomorrow and post. No promises I’ll remember. Lol.

I don't think that's the problem he's worried about. I believe he's saying that the carb reaches wide open throttle when the sticks are at 3/4. Basically needs a longer arm on the throttle shaft I think. Not sure what the correct fix is. I wouldn't really want to use the extension posted above. I'd like the correct length lever.

I've never had a boat that the carb or throttle body wasn't at full open before the throttles were all the way forward.
That being said, depending on what controls you have, there may be different places you can attach the cable ends to change the amount of throw

lol, thanks. Pic caught my eye before reading, saw the cable, and thecrest is history....lol

I’m with others. Check for other cable mounting holes on throttle levers. Closer to axis point will provide more lever movement to wide open throttle while further from axis point less movement.

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.

So I have the original Kiekhaefer controls. The cable is at the very end of the lever as it is. There does not seem to be any other option to attach the cable anyway, but yes, I am getting full throttle at the carbs when the sticks reach almost 3/4 of there travel. Not only will this create a potential future break point but also gives a quick throttle response which feels unnatural instead of more progressive feel. Do I need to look at other controls like Lavorsi? Id rather just keep the ones I have if I can make it work. I tried to lengthen the link at the throttle but all it did was change the mount position of the cable holder. The effect remained the same.

Am I thinking wrong ? You need to mount cable higher up toward shifter pivot point, not lower ?

SB, It seems to me that the closer to the axis point the attachment is, the less the travel would be. Problem is, I dont see another attaching point available on this control.

Can you drill another hole lower on the carb lever?

There are other holes that I did try, closer to the axis point & further away. No help at the carb end. All it did was change the location of the cable anchor point.

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*

For the cable and carb linkage per movement of shifter lever above pivot point, but further travel for the top of shifter handle.

Draw it on paper. Shorter and longer arm below pivot point. And put shifter top in diff positions.

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.

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..?...

You can get a bolt on throttle stop so that no force will be put on the shafts.

Lolololol sounds like an old girlfriend. :)

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

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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.

That's the part. Can do it my way too, mentioned earlier.
Thanks for seeing what I saw. :)

This is the answer.

Ill give it go & report back. :) First I have to customize a tail pipe that I had custom built.. Sigh... :(
Always something....

Move your morse cable holder on the bracket all the way to the back.
Screw you heim joint on as far it goes and if needed cut a 1/4 inch off the cable end.
I think both of these will get it real close

Zero Effort controls have adjustable stops at both ends of travel. SOME of the older ones have 2 cable attachment points, each w a different throw. I cant find a picture of one, though.

NautiB,

Did you end up getting a different throttle arm or making an extension to fix this? I am having the same issue now, with holley dry throttle bodies, throw on controls is only about half at wide open at throttle bodies. Like some have mentioned I too really would prefer to just have the correct throttle arm for the 3" throw. Just was curious what you found out, if I am going to sit on hold with holley just for them to show me the sniper extension arm posted above haha...


Thanks!