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1967 cd-24 seems to have dead spot in fire at mid rpm

Could be too much prop. I will check mine when I get home. I run about 10mph as a kicker on 16 alum v with 30hp main eng and 3 people and gear.
 
Just pull the slow needle knob off and keep turning it that way until fully seated then count the turns out 1 1/2. You will never hit a plane on a 14ft boat period. Adjust the slow needle for the fastest rpm in forward gear on the water never run it past high idle speed in neutral it is the same as running without oil it takes alot less fuel for the engine to run away.
 
Mr Reeves also has a thread to set low speed. If your motor ran faster before, then we have to find the problem. My old 6 will still run with the best of them. How about your trim? What hole is it in, 1st or 2nd?
 
I dunno how it ran before. This was a recent purchase to fix and use. I adjusted the idle screw by removing the actual knob still same result if I unscrew the 1.5 turns the engine starts to miss I crank it in and clears up but to the point I pretty much lose low idle. Does the same with people in the boat or no extra people it runs 5 mph with a touch of 6 every now and then. But still an rev in neutral easily.
 
I don't remember that you did a compression test, if so. What were the results? If both cylinders are the same, but low, then the gasket has failed between the cylinders which is quite common on these little twins 3, 4. 4.5. 5, 5.5 and 6 hp. Often resulting from a one time overheat. Is the paint discolored on the head?
 
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I've replaced the head and head gasket due to a stripped spark plug thread. the head I got was supposed to be good but it does have a small chip in the spark plug seal face I have just looked and seems it was leaking there I thought I had a fix for it but it didn't seem to be working. I have tried something else to see if it will work. If it does that may have been my problem we shall see. Would a small leak at the spark plug cost me half my rom and power ?
 
If you want faster you need more HP period you can not equate speed with engine performance. Get the engine running proper WOT rpm and the speed is what it is. You can definitely try a prop with less pitch bur doubt you will gain much speed but you will increase the service life of the engine by not lugging it down. You can put a go cart motor on a drag racer but dont expect to win any races. A nice healthy 15hp will get your boat on a nice plane that 6hp is nothing more than a kicker.
 
You can borrow a tach timing light from your local auto part store all you need is a motor cycle or law mower battery to check wide open throttle rpm. You want to see 4500 rpm for that engine.
 
kimcrwbr1 said:
If you want faster you need more HP period you can not equate speed with engine performance. Get the engine running proper WOT rpm and the speed is what it is. You can definitely try a prop with less pitch bur doubt you will gain much speed but you will increase the service life of the engine by not lugging it down. You can put a go cart motor on a drag racer but dont expect to win any races. A nice healthy 15hp will get your boat on a nice plane that 6hp is nothing more than a kicker.
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Im not trying to make a speed boat. I have an 18hp fastwin that pushes the boat plenty fast; however, I see videos and hear others say their six hp pushes within a certain range and mine is half of that I can safely assume something isn't right. If something isn't right I would like to correct it. My engine seems
to run maybe half the wot rpm that it should when in the water. If it's wore out, fine, but I wanna make sure it's not something else, that is fixable, before I write it off. I tried a prop smaller than which originally came on the motor and is still very sluggish. Choke doesnt seem to pick it up any which leads me to believe it's not a carb issue. It's not a fuel delivery issue because the carb is full when I unplug it and pumping the bulb doesn't change anything. If you have anything else to check I'm very receptive.
 
I'll check rpm on my next lake run. I have one that spins on the crank for in water testing it should get me close. I'm betting it isn't even pushing 3500
 
I mean I'm a way it seems it is cause the idle needle has to be so far in its maybe at 3/4 of a turn before seated which is half recxomened anything more than that out it starts missing.
 
Then check again for proper main jet and it isn't reamed out by some fool and also that donut type ring in base of float bowl is properly sealing. Sounds to me like its running too rich to crank up properly. But what do I know I've been at this outboard stuff for only 51 years. Maybe our REAL veteran, Mr Reeves should speak out. It's hard to tell without hearing and "feeling" it run. As was mentioned, its not a racing outboard. But its nice if you can run with the others in the 6hp range. My 65 will plane a 14 ft aluminum boat with just me and the gas can up front. I weigh 190. It has 3500 hours on it.
 
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Alrighty I will check the jet and carb again. I do have to choke it to start it basically every time. I appreciate all the replies and hope to solve any issues I can. I've tried posting a video or picture but it seems difficult or I'm just not seeing the right button. We'll see what happens.
 
You have to choke it because your low speed is set lean to compensate for problem of rich at high end. So it is harder to start. Spark plug leak sounds insignificant, check with soapy water. You can carefully dress surface and get most of scratch out. I have an assortment of tools for that.
 
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