Throttle Adjustment
 

I recently repowered my '97 Baja from my 502 EFI to a HP500 carb motor and I am having an issue with my throttle control. When my motor is at WOT the throttle control is only a little over half way of its range. Is there an adjustment I can make to cure this? The controls are the original Keikhaffer and when I pulled them out I did not see any way to adjust the cable. Anyone had a similar issue? I am reinstalling the 502 EFI after it is rebuilt so I can live with the issue, but i would like to have my full range of movement in the throttle. Thanks in advance!

I think that the EFI motor linkage did not have a long stroke range that you need for your carb. I think you have to adjust it at your levers. You have to move the cable down on the lever for more stroke

Your throttle does not have any adjustment for the amount of throw it has. You have to move the cable connection farther out on the carb. There are multiple holes in the carb. You should probably be in the outermost hole. If it is a very large hole in the carb linkage, then you need to install some bushings to reduce the size of the hole. Holley makes some brass bushings to reduce that hole to 5/16" I think. The farther out on the arm of the carb you go, the more movement in the throttle you will have. Hope this helps, Eddie.

You are correct, no adjustment at the control. The cable connection is at the farthest hole on the linkage at the carb. I could probably make an aluminum plateto entend the connection further. Do you have any idea how much would need to be added for full movement? Thanks, John

If you can, take a pic of the carb linkage and post it here. Something is not right. You should have full range of travel with the cable in the outermost hole on the carb.
I have seen carb linkages cut off to shorten them. Just a guess as to what may be wrong. Post a pic so I can see what you are dealing with. Or you could email it to me at [email protected].
Eddie.

I had to make an extension (Silver piece) to bring the cable out further on the linkage.

that linkage bracket has been cut short. look in oso classifieds, I seen some brackets there, samething just longer tail piece.
Larry

Larry , not sure if you mean me or not. If you are refering to the pic I posted, nothing has been cut. I made what you see in the pic.
Mike

I will get a pic posted up tomorrow. It does not make sense to me either, hopefully the pic will help.

that piece you made ... was it to increase the throw? I have the same problem after going from stock carb to 4150 ...I only get about 75% of the sticks movement and not a positve stop .... its annoying as H ell !!!

Hi Mike, I thought that was a pic of bghert's set-up, I have the same looking bracket on mine, just with a longer tail and more holes, good job on the fabbing, it looks just like my eddie marine special, sorry about the mix up.
Larry

OK, I'm starting to catch up, you made the bracket that attaches to the carb throttle plate bracket, not the yellow cable bracket, correct? Is that a quick fuel 4500 carb?
Larry

Yes, The reason for the three holes. Adjustment. Some of the stock merc. setups have piece for the increase.

I did my adjustments at the throttles/shifters with stops vs. at the carb. This gives you a positive stop with no pressure on the carb linkage. Also, I personally like the shorter throw.

Yes to the bracket. Carb is a 4150, custom built by Tim Zepp engines in New Jersey. Body is a Pro Form with anular boosters .Metering plates and throttle plate are billet.
Mike

Here is a pic of my current linkage. I do not see anymore room for adjustment and I am annoyed with being WOT with the stick half way.

I had the same problem. Look at the pic in post #6. Click on it to make it larger. You will see the the Alum. Piece I made and bolted it to the carb linkage to extend the cable out fruther. You need to move it about 3/4 of an inch. You'll have to play it a little. Not very hard.

So if I am looking at it correctly the alluminum piece is bolted tot he original location of the throttle cable and simple extends the mounting location another 3/4". I am pretty sure I simple minded redneck like myself can figure it out. Did you have someone make that aluminum piece for you, it looks like it was machined.

I would not mind having the shorter throw, but i have hardly any movement before I am WOT. It is very annoying when I am trying to cruise at 3000. Your setup looks killer though!

I have the same problem after going from a Holley to a barry grant. WOT is at half. I get a ick out of the looks I get when I'm doing 70 and people see the throttle at only half:D

Well the only way I see 70 is behind my powerstroke, but I guess I am still running 64 with half throttle (so they think).

come on you 2, more power. as we get older we need more HP to cope with ED. Ha-Ha

Made it myself. Just a 1/4 X 1 piece of alum. Drilled several holes for the adjustment.

More power is coming after this season. Until then I will just have to run at the back of the pack.:(

Very good. I will do some fabricating this weekend. Thanks for the tips.

Just leave it alone for another week and those Table Rock Crownies will eat your lunch at 64 mph....:D

Problem Solved. I made an aluminum plate to extend the mount 3/4" and it worked out perfectly. Thanks everyone for the comments and advice. Unfortunately all that work and I will still be running the same speed.:(

LOL. I will do my best to run with the Crownies next weekend and not disgrace the Baja name. I did change props so with a little luck I may be able to hit 65 and i can only imagine there will be a couple of Crownlines running that speed, but we will see.

I know you got it fixed bit for future reference...
Morse cables come in a zillion lenghts and strokes. If you measure from the end of the threads to the detent ring in the cable (where the cable is snapped in to the bracket) and go to a industrial supply place or their website (http://www.teleflexmorse.com/CableControls.html) and look on their chart you can see what the stroke of your cable is and what's available. The length you measure is NOT THE ACTUAL STROKE!!! Measure the cable on a simillarly equipped boat if in doubt. Ok - I am done saying stroke, buddy, cable, and lengths in the same post. Hope it helps.

I dont think any of that is revelant here ......m

My Apologies! Others have helped me and I was just trying to pass on what I learned in a similar circumstance. I'll Gladly Refrain. Don

T38 ....my post wasn't meant to be negative but it did sound that way ...:drink: .... Just a comment about the stroke of the cable was not a solution to this prolem ....:ernaehrung004:

Cool. THANKS! But if you were to change the stroke/travel of the cable the additional bracket would not have been neccessary and the carb and throttle combination could be made to work. And when I learned about the cables, after lots of running place to place lalala, I found I could walk in and say this is what I have, this is what I want to do and I was Literally done and on my way in 15 minutes.

throttle
 

I'm a little unclear on one thing guys. But, if you move the cable to the hole farthest from the shaft on the carb, you lessen the movement on the carb for the same handle throw, which was the issue, not make it greater, which is what I understood the problem to be. Clearly, the opposite will be true from the throttle position.

Just my 2 cents worth.

The arc is larger ..it takes more movement of the throttles to move the shaft to WOT ...thus the throttles have to move more forward ........m