Johnson 5.5HP CD-17 help needed

[cr9c1]

Re: Johnson 5.5HP CD-17 help needed

I double checked all the jets on the carb again and put new packing washers in just to be safe and all, and it still runs better with the high speed screw all the way in, bottomed out.

Im wondering if because the mixture I have is currently 50:1 if that has anything to do with it.

 

[steelespike]

Re: Johnson 5.5HP CD-17 help needed

Oil mixture doesn't affect mixture screw settings.You have too much gas somewhere.Maybe it's just the float valve not working right.If it is flooded unhooking the gas line it might stall early as the gas goes down with the highspeed closed.Normally the motor will speed up briefly just as the gas runs out.With the highspeed closed I think it my simply stall as the gas reaches normal level.If the gas is getting through the jet somehow it will have to empty the bowl to stall.

 

[cr9c1]

Re: Johnson 5.5HP CD-17 help needed

Weird. Its not doing anything out of the ordinary. It runs great. Has real good power, plains my boat now with just me in it. Goes right along good. No stalling, no gas leaking anywhere, nothing. Idles right down, and goes right up to full throttle effortlessly.

Float, needle valve, and seat are all brand new.

 

[samo_ott]

Re: Johnson 5.5HP CD-17 help needed

I'd leave it if it runs great! No use digging too deep! Use it and have fun

 

[cr9c1]

Re: Johnson 5.5HP CD-17 help needed

Now I'm starting to think the user who said, its getting too much fuel somewhere, is right. It doesn't seem to have a whole lot of power when you hammer the throttle down. Even my 25HP evinrude on my 14 foot 700 pound boat loaded with two coolers full of beer, and 5 grown adults really leaps when you throttle her up.

This one sort of catches up to itself after a while but its nothing impressive like I'd think it should be.

Anyone else know where I should start looking? I've replaced all the packing washers, the needle, seat, float, the red fiber washer that sits on the main jet in the float bowl, the core plug on top, all the jets are clean and I removed the main jet as well to check for gunk. All checks out good. Runs great, but it runs like crap if that High Speed mixture is anywhere but closed at WOT.

 

[wbeaton]

Re: Johnson 5.5HP CD-17 help needed

After 24 replies I guess I should throw my two cents in too. Steelspike, FR, et al are right. Your high speed jet isn't closing off the fuel when you have it turned in. Is the high speed jet or seat damaged? Are you sure its screwing in all the way? I have had old packing restrict the hole so much that it actually stopped the needle from completely seating. Did you remove all the old packing before adding the new washers? Also, did you wrap the float needle spring around the base of the float needle and clip it to the float?

Your 25 hp sounds like a hell of a motor. My 1988 30 hp Johnson couldn't do that with half that load.

 

[cr9c1]

Re: Johnson 5.5HP CD-17 help needed

Thanks. The 25hp is a great motor. I got it in its virgin years, if it had 20 hours on it I'd have been suprised. It doesn't push the boat very fast with 5 people, and two coolers full of beer, but it moves it and it shoots out of the hole.

Yes, I did make sure to remove all the old packing out of the needle seat. I will have to remove the bowl and see if the needle is indeed going in all the way. Its such a pain in the arse to do this. The motor runs beautiful at low speed but doesn't seem to "Jump" like it should when I come on to it.

Im fairly certain the washer that goes between the float bowl and the carb (Sits around the main jet) is the right one too. Of course the carb kit I bought had all kinds of useless parts in it to confuse me.

I installed 2 packing washers in each of the high speed and low speed needle seats. This is correct, right?

 

[cr9c1]

Re: Johnson 5.5HP CD-17 help needed

Bump. Anyone? Inevitably I'll end up tearing it apart again, but I would like to have some other input to know what I might want to look for when I tear into it.

 

[cr9c1]

Re: Johnson 5.5HP CD-17 help needed

Okay. I tore it apart again. The high speed needle is indeed all the way turned in. I checked everything. All the ports are clean, and when I did the rebuild, I removed the core plug on top and all them ports were clean. No dirt or anything. Everything is free flowing. The only thing I can think of is someone changed the jet in the carb to a fixed high speed jet and never put the fixed bowl on.

Does anyone have a picture of the jet for a CD-17 or a breakdown of the carb so I might be able to get a better idea of whats going on?

 

[wbeaton]

Re: Johnson 5.5HP CD-17 help needed

Is the jet in good shape? It should come to a point with no grooves or shoulders. If the jet has been turned in too tightly too many times it will damage the jet and make setting impossible.

 

[cr9c1]

Re: Johnson 5.5HP CD-17 help needed

The jet seems to be in excellent shape but I have nothing to compare it to. Its the first outboard I've had with a low and high speed mixture, and by far the oldest in my collection. I toyed with the idea that someone put a fixed high speed jet in it and thats why the mixture has to be completely leaned out.

 

[wbeaton]

Re: Johnson 5.5HP CD-17 help needed

The jet should come to a point like a perfectly sharpened pencil. The edges leading to the point must be perfectly straight and true. If your high speed jet has a knob on it then you don't have a fixed jet.

If the jet is fine and seating then there isn't much else I can tell you. Could be your motor is running the way it should. A 5.5 hp isn't going to have much power out of the hole. In fact, a 7.5 hp won't even plane one of my 12' boats.

 

[cr9c1]

Re: Johnson 5.5HP CD-17 help needed

Okay. Maybe I'm on the wrong page with you. My high speed needle comes to a point. The Jet I was referring to is the removable one that you can unscrew that goes straight up through the throat of the carb. I'm not very familiar with the highspeed adjustable carbs. All I've ever had is carbs without a high speed adjustment. I just can't imagine that having the high speed needle screwed in all the way (lean) is operating the way it should be. Its definitely getting enough fuel to the motor because I can see it spraying through the carb and the engine runs real good. A lot better than it did before.

 

[wbeaton]

Re: Johnson 5.5HP CD-17 help needed

That is the high speed nozzle. The high speed jet controls fuel flow to the nozzle. All the way in should shut off flow to the nozzel. Therefore, your problem is before the nozzle.

The edges of the jet leading to the point also have to be perfectly straight. No groves or shoulders to meter fuel properly.

 

[cr9c1]

Re: Johnson 5.5HP CD-17 help needed

Okay. I wonder if the float bowl itself (Since the high speed mixture adjustment is in that) is screwed up. Its hard for me to tell because the holes are so small but I'll keep looking into it. It runs real nice with it closed off all the way but it just doesn't seem right to me.

 

[F_R]

Re: Johnson 5.5HP CD-17 help needed

A little bit of sanity will tell you that the needle screws down against a hole in the float bowl. All it does in God's wide world is shut off the flow of fuel through that hole, sort of like a faucet. If it is not shutting off the fuel flow through the hole it obviously is not seating in it. The hole could be corroded out of round as you sort of suggest, or the needle isn't actually going all the way in. There is only one other route for the fuel to get to the main nozzle and that is through the gasket that everybody has mentioned a dozen times.

Take the bowl off and inspect the seating of the needle in the hole, and look for any other bypassing possibilities. It is not rocket science.

 

[cr9c1]

Re: Johnson 5.5HP CD-17 help needed

Guess I'll have to take it apart again. I put all new washers and stuff in it from the carb kit I bought. The one I put between the bowl and carb was a red soft type washer. I didn't have anything to compare it to since the old one fell apart when I took it apart so perhaps the hole the needle seats into is out of round as suggested earlier. I replaced all packing washers, two for the low speed, two for the high speed. I also took the core plug out and made sure all the holes were open and clean there. No gunk near the main jet or under it. Carb is completely clean, other than my problem with the high speed.

 

[cr9c1]

Re: Johnson 5.5HP CD-17 help needed

Well I guess the gasket that is supposed to seal the main jet and the float bowl off so fuel doesn't leak into the jet wasn't enough. I fabricated some washers today out of gasket material to test my theory and its working fine now. No more high speed needle buried out of sight.

Thanks ya'll.