Adjusting throttle cables
 

I have Keikheiffer throttle on a 454 trs setup. After pushing the throttles to 3500 rpm I back them backdown to the lowest setting but the rpm are still a little high like 1200. I can manually push the throlltle housing forward and the throttle goes to its lowest setting and idles properly. So I think my throttle housings or cables need some adjustment. Does anybody know how to do this? Thanks

Re: Adjusting throttle cables
 

How about a stronger throttle return spring?

Re: Adjusting throttle cables
 

Where would I find that on the cables or on the carb?

Re: Adjusting throttle cables
 

take the cable off the catb and turn the end until it lines up perfectly with the stud or ball. Then turn it in 3 turns and your in buisness. you should have a little tension on it and that works alot better then a stiffer spring. Cables will stretch over a period of time and need to be adjusted periodically.

Re: Adjusting throttle cables
 

Ok, let me see if i get this straight.
You want me to take the cable off of the carb. Turn the end of the cable. By twisting the cable or??? I'm not sure what you mean. Please be more specific.

Re: Adjusting throttle cables
 

You should see a little stop nut at the cable end where it threads on the red connector. Remove the red connector from the throttle arm, loosen the stop nut and turn the connector out or counterclockwise. Re-tighten the stop nut and reattach to the throttle arm.

Re: Adjusting throttle cables
 

How many times should I turn the nut? 3x like Hillbilly24 said?

Re: Adjusting throttle cables
 

That should be fine to start. You may need to experiment. Also make sure all the connections on the engine brackets are snug. Not too tight as things will bind up.

Re: Adjusting throttle cables
 

It adjustments worked great on both engines. Then the port engine had high rpms again around 1500 only after I shifted from forward to neutral and reverse then back into forward during my parking maneuver. Inotherwords, on my test run both engines returned to idle perfectly just throttleing up and down many times. Only after shifting gears, the port engine would not return to idle hung around 1500rpm. What do you think I should do now? Should I continue to counter clockwise adjust the cable or some kind of other adjustment is in order???

Re: Adjusting throttle cables
 

try giving it a little more tension with the cable before you replace the spring. The stiffer the spring the more jumpy the throttle will get. It will require more initial force to move the throttle wich makes fine adjustment hard. If this still doesnt work, try and back it down manually at the carb again if yo still have slack tighten it more, if not you need to adjust the carb.

Re: Adjusting throttle cables
 

What adjustments would I need to make on the carb?? If the cable doesn't work??? Does shifting in and out of gear have any bearing on this situation??

Re: Adjusting throttle cables
 

If you have segregated throttle and shift, then no shifting has nothing to do with the problem. Make sure the throttle is completly closed by puching the throttle arm on the carb by hand. if it closes further, then the cable needs more adjustment, if it is closed all the way, you need to adjust the idle speed screw, you should also adjust the idle mixture screw at the same time. The idle speed screw is the one that the throttle arm rests against at idle, to lower the idle rpm, back it out. you will need to adjust the cable again after you do this. To set idle mixture you will turn the screws on the bottom front of the carb in until the engine stymbles, then count how many turns out it takes to make the engine stumble again. Then center it between the 2. Lets say you turn it in till it stumbles, then it takes 3 turns out from there to get it to stumble again, you should turn the screw back in 1 1/2 turns. If the engine has no response to adjusting the idle mixture screws then it needs to be rebuilt. I'm not explaining that procedure on the computer though :D :D :D

Re: Adjusting throttle cables
 

Always do what Hillbilly24 says. He is ALWAYS right! :D

Re: Adjusting throttle cables
 

Ok, now that I made the adjustments to the cables, the two individual throttles seem to be off just a little bit. So how do I fix that problem. I like the two throttle shifters to be in sync at the same clicks through the throttle range. Also, now it takes more movement on the throttle to get an initial respose in RPM. Also, I noticed my setup doesn't have a return spring unless its located on the other end by the throttles????

Re: Adjusting throttle cables
 

You should have atleast a light return spring on both engines, just go to Napa or something and buy em for a buck a piece. This alone may bring the throttles back to even. If not put a little more tension at a time on the side that is too far foward and it will suck it back to even eeith the other. They will take a little more motion to get an initial throttle response but this is the right setup and they will require the same amount of movement when you are done.

Re: Adjusting throttle cables
 

What does the light return spring look like and where should it go on my setup? There is a return spring in the diagram. Is that the light return spring you are talking about or is that the heavy one? The Heavy return listed in the diagram is not on my current setup. What would the light one look like and where should it go?

Re: Adjusting throttle cables
 

It's # 12 on that diagram. It goes between the ear on the plate that the cable housing ataches to, and the throttle arm on the carb that the cable end attaches to. Does that make any sense? What I meant by light reurn spring was similiar to the factory one, and not to use a stiffer one from an auto parts store to band aid the problem.

Re: Adjusting throttle cables
 

I don't think I understand,I'm probrobly a dumb***, but are you saying in the diagram one end attaches to one of the holes just above number 16 and the other end attaches next to the red plastic thing I was turning counter clockwise?

Re: Adjusting throttle cables
 

yes one end goes to one fo the wholes just above #16, the other end goes to the arm just above #7, that has the stud sticking out that the throttle cable end attaches to. there should be a whole or a hook for it to atach to.

Re: Adjusting throttle cables
 

Ok, I think I got it now. I will give it a try and let you know what happens. Thanks Hillbilly24!!!

Re: Adjusting throttle cables
 

I'm adjusting the carb on this 420 HP engine. What should the correct idle RPM be? Then what should the rpm be on the first click position on the throttles? Your imput is very much appriciated!!

Re: Adjusting throttle cables
 

I'm not certian on the exact idle spec but somewhere around 650-700 RPM, maybe just a little higher if it stalls when you drop it in gear in in the water. There is no spec for RPM with throttle at first click, that will vary widely from engine to engine.