Low to no idle, and no WOT

Thompy_04

Petty Officer 1st Class
Joined
Jun 16, 2004
Messages
216
Ok, I'll make this as short as possible. 1960 Jonny 18 HP. All new ignition parts, but plug wires, rebuilt and tuned carb, points set at .20. It doesn't want to rev at idle, I mean hardly at all, when the line is at start, thats a low idle just enough to keep it running. It'll start and sit in neutral and run all day long, but won't rev very high at all. Was this motor not ment to idle very high? To get it to rev at a decent rate in neutral is to lean it out so much that it dies when put in gear. Sometimes, if trolling or at prolonged low idle in gear it'll cut out, and have a hard starting again. I've went though the low speed needle 20 times or more. I've got to thinking, could it be that my top crank seal has been spent? I don't see any oil on the plate, or bleeding though from coil slots, but a little bit on the seal itself. I've got a seal on order, but I need to know how to install it. <br /><br />Next, where can I pick up some plug wires, and what do I need to get? The wires are getting a little damaged, and I cut them to get rid of some of the bad, but unfortunately I cut them a little short. Now it tends to pull the top plug out of the coil. It'll make a connection and scream at WOT, then loose the connection and only run on one cylinder. Runs real rough at the mid range, but I think the sync is off justtttt a little bit, and the spark is working hard at that range anyway and the bad plug connection could be contributing. Any suggestions with the mid range as well? <br /><br />Sorry for the long post, but I wanna make things as clear as possible. If you guys can give me any info, that'd be great!<br /><br />Oh, and by the way, compression is absolutely great, took the head off and the cylinder walls look brand new, and the pistons hardly have any carbon on them.
 

fireman57

Captain
Joined
Aug 24, 2004
Messages
3,811
Re: Low to no idle, and no WOT

You said that your compression is great. Please post your numbers. You can get new plug wires at your local jonnyrude dealer. Sounds like you need to soak and rebuild your carb. Make sure that you blow the passages out well with compressed air when you are done. You might have a cork float in that one and the rebuild kit from your dealer should have a new plastic one. You also will want to check spark.
 

Thompy_04

Petty Officer 1st Class
Joined
Jun 16, 2004
Messages
216
Re: Low to no idle, and no WOT

I've rebuilt the carb twice, new plastic float in it by the way. Compression numbers both of them are at 110. I'd say this motor had every bit of 10 hours on it, but the previous owner didn't take very good care of it. My local dealer doesn't have wire, so I'm going to take an hour trip to get some. I believe I'm going to go through the carb again, maybe the float is set a little low. I'm also going to take the top seal out and replace it.
 

Silvertip

Supreme Mariner
Joined
Sep 22, 2003
Messages
28,771
Re: Low to no idle, and no WOT

Idle speed is not adjusted using the mixture screws. Idle mixture controls idle "quality". The idle speed adjustment is a separate screw on the linkage. Idle mixture and speed adjustments need to be made in the water, not on muffs since there is no exhaust back pressure. Adjust the idle speed so the engine stays running. Adjust the mixture screw for smooth idle, then back down the idle speed and reset the mixture until both are where you want it. Get your plug wires sorted out as it appears thats a problem as well. Don't use carbon core plug wires. Use copper core which is available at most auto parts stores in bulk. Buy a few feet, get new boots and terminal ends and make your own.
 

Thompy_04

Petty Officer 1st Class
Joined
Jun 16, 2004
Messages
216
Re: Low to no idle, and no WOT

Wait a minute. I think we're on the wrong page here. When in neutral, the motor won't rev hardly at all, just enough to keep the motor running and thats the highest the idle will go. I realize the speed is not adjusted by the needles. And I do set the idle mixture while in gear, in the water, moving at that. I don't believe with the boat on the trailer it does me any good. Oh, and by the way. Will any copper core wire work? I got some from my Johnyrude dealer, which I had to drive an hour there and back, but I didn't get enough. I totally forgot about the wire wrapping around the armature plate and ended up with a shorter wire for my bottom plug. <br />I've got a seal on order, as the dealer used the seal I ordered today for another motor they are rebuilding. I also got a hold of someone who has the seal puller, but they want a $100 deposit to make sure they get it back. My dad, and myself have delt with this guy, and from my memory and my dad's he's not real honest. With that in mind I'm leary to fork out a hundred bucks to him for a seal puller, for fear he'll try to take me for it. I'll find one eventually. I really need to replace the top crank seal, as there is some oil starting to leak out underneath the armature plate. It's not all over it, but its in the beginning stages or going out.
 
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