1958 3 hp Lightwin low speed idle

[mikeaga]

I am starting a new thread instead of adding on to my existing one. I believe enough has changed that the original is not relevant. LOl I have taken the carburater apart and changed out the parts recommended in the tune up article. I have put it back on the motor. After a couple of pulls the darn thing started! It runs pretty good at full throtle. I messed with the low speed and can't seem to get it to idle. I am running it in a garbage can with the water almost to the top. A couple of times when I tried to resart it a lot of fuel leaked out of the throat. Do I need to do a complete rebuild or did I do something wrong? This is my first outboard motor repair so please forgive my ignorance. Thanks.

 

[kfa4303]

Re: 1958 3 hp Lightwin low speed idle

Hello again Mike. Glad you're making some progress. If fuel is coming out of the throat of the carb, then it's flooding which is usually just due to a stuck float needle. No biggie, just remove the carb from the motor and take the lower bowl off. Once it's removed, take special care to see that the little metal needle that rides on the carb float is not hung up in any way. You should be able to more the float up down through its range of motion without hindrance. Once all looks well, replace the bowl and put the carb back on the motor.

Here's a great link. Pay special attention to section regarding the float needle about 1/3-1/2 way down the page. Hang in there. Just a little tweaking and she'll be purring like a kitten.
http://www.outboard-boat-motor-repa...Johnson 3 HP 1952-1967 Carburetor Tune-UP.htm

 

[Joe Reeves]

Re: 1958 3 hp Lightwin low speed idle

Assuming that you know where the water pump is located..... Just have the water level a couple inches above the water pump. DO NOT have the water level so high that it may result in excessive exhaust flow back pressure.

(Carburetor Adjustments - Two Adjustable N/Vs)
(J. Reeves)

Initial settings are: Bottom high speed = seat gently, then open 1 turn out. Top slow speed = seat gently, then open 1-1/2 turns.

Setting the high and low needle valves properly:

NOTE: For engines that DO NOT have a shift selection, obviously there is no NEUTRAL position. Simply lower the rpms to the lowest setting to obtain the low speed needle valve adjustment.

(High Speed) Start engine (it will run pretty rough), shift into forward gear, take up to full throttle. In segments of 1/8 turn, waiting for the engine to respond between turns, start turning in the bottom high speed needle valve. You'll reach a point whereas the engine will either start to die out or spit back (sounds like a mild backfire). At that point, back out the needle valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest setting.

(Low Speed) Slow the engine down to where it just stays running. Shift into neutral. Again in segments of 1/8 turns, start to turn the top needle valve in. Wait a few seconds for the engine to respond. As you turn the valve in, the rpms will increase. Lower the rpms again to where the engine will just stay running. Eventually you'll hit the point where the engine wants to die out or it will spit back. Again, at that point, back out the valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest slow speed setting.

When you have finished the above adjustments, you will have no reason to move them again unless the carburetor fouls/gums up from sitting, in which case you would be required to remove, clean, and rebuild the carburetor anyway.

 

[lindy46]

Re: 1958 3 hp Lightwin low speed idle

Did you install a carb kit, or just clean it up? I usually find a poor idle condition on these motors due to failure to remove the core plug on top of the carb and clean underneath it. That is the idle circuit and gunk can accumulate in there and block the small holes, causing poor idle.

 

[mikeaga]

Re: 1958 3 hp Lightwin low speed idle

Two questions. How do I remove the core plug? I was wondering about that area. Since that is where the low speed needle sits. Does the float measurement from where it pivots to the other side need to be the same. Also there was a lot of play in the float where the prongs hook into it. I tried to wiggle this a little and the float broke. So I am ordering a new float. The float looked kinda rough when I took it apart the first time. Does anyone know the part number for this float? The parts source on this website does'nt go back to 1958. Thanks

 

[1946Zephyr]

Re: 1958 3 hp Lightwin low speed idle

I would try and get a plastic float if possible. They hold up so much better and are more bouyant.

If you're afraid to pull that plug out of the top, then get the carb cleaner in the spray can and remove the low speed needle. Hold the carb to where the hole for the needle is facing down, then poke that little red nozzle up in there and blast away. This usually works pretty good.

Once you get a new float, make sure that the little spring clip is on the needle. It is there to help pull the needle open, when your carb is empty.

Once you get that bugger running, you'll probably end up turning the high speed in, to where it's a 1/2 turn out. I have found that a lot of motors, 7.5hp and smaller run good at 1/2 turn out.

 

[nwcove]

Re: 1958 3 hp Lightwin low speed idle

Two questions. How do I remove the core plug? I was wondering about that area. Since that is where the low speed needle sits. Does the float measurement from where it pivots to the other side need to be the same. Also there was a lot of play in the float where the prongs hook into it. I tried to wiggle this a little and the float broke. So I am ordering a new float. The float looked kinda rough when I took it apart the first time. Does anyone know the part number for this float? The parts source on this website does'nt go back to 1958. Thanks

the float should be omc # 0396514.

 

[Joe Reeves]

Re: 1958 3 hp Lightwin low speed idle

How do I remove the core plug? Does anyone know the part number for this float?

Core plug...Use caution as the carburetor throat is about 1/4" below that plug. Use a blunt center punch in the middle of the plug to cave it in, then using a pointed scribe, insert it just enough to pry it out.

Float original part number is 375919 but supersedes up to part number 396514 .

 

[1946Zephyr]

Re: 1958 3 hp Lightwin low speed idle

Yep, that 396514 is the plastic float. I got two of those from marineengine. That will work a lot nicer than the older style cork ones will.

 

[kfa4303]

Re: 1958 3 hp Lightwin low speed idle

Hello again Mike. Anther trick for removing the welch plug is to use a small screw and simply thread it into the plug and pry it out. Scroll down about 1/2 way in the link below for pics.

http://www.outboard-boat-motor-repa...hnson 5.5 HP 1954-1964 Carburetor Tune-UP.htm

It's not uncommon for the old cork floats to fall apart after all this time. You'll need to get a new plastic one, but it will last forever and you won't have to worry about bits of cork clogging up the passages in the carb. The float should sit level when you hold the carb upside down. (use pics in link above)

This should be the float you need.

http://www.iboats.com/Carburetor-Fl...54.1958--session_id.408533530--view_id.174136

Here's a parts catalog too.

http://www.marineengine.com/parts/v...evinrude-johnson/ITEM_2918/ITEM_291800001.htm

 

[1946Zephyr]

Re: 1958 3 hp Lightwin low speed idle

kfa4303, what motor is on that boat in your signature?

 

[kfa4303]

Re: 1958 3 hp Lightwin low speed idle

That's my '66 20 hp Johnson on my '59ish (?) 14', semi-V hull, Arkansas Traveler tinny runabout/ghetto skiff thingy. The 20 hp is just an old 18 hp with different reeds, or something. I've also had a '60s era 10 and 33 hp motors and the 20 hp really is a perfect balance between the the two. It will push me along at +20 mph, get on plane in about 10 sec., and run around at all day on about 3-4 gallons of fuel, but it's still light enough to pick up with ease (approx. 80 lbs.), if need be. Best of all, it's super reliable. She starts in 1-2 pulls every time and will idle down nice and low so I can cruise around in the Manatee/no wake zones all day without issue. About the only problem is the white paint (hard to keep clean on an old 2-smoke) and the infamous rattling cowl, but I've cobbled together an extra thick gasket that keeps the racket to a minimum. I've also mounted it on a transom riser and added a PVC tiller extender and gear shift lever. Between the two, I can sit or stand to drive and shift through all of the gears while still facing forward by simply reaching back with my right hand to give the shift extender a tug to put it into FWD, or a push to put it into REV. Now if I could only double the hp for free it would be perfect

 

[mikeaga]

Re: 1958 3 hp Lightwin low speed idle

Does the clip come with the float, because mine did not have one?

 

[nwcove]

Re: 1958 3 hp Lightwin low speed idle

the clip should come with the kit. not with the float.

 

[1946Zephyr]

Re: 1958 3 hp Lightwin low speed idle

If it's an older needle, without the groove on the bottom, then it never had one. Original style needles typically don't have them, because a lot of them ar hard tipped, versus rubber. However, like nwcove said, it'll come in a carb kit.

 

[1946Zephyr]

Re: 1958 3 hp Lightwin low speed idle

Nice outfit kfa

 

[kfa4303]

Re: 1958 3 hp Lightwin low speed idle

Oh thanks, Zephy. She's nothing special, but she gets me there and back again and is surprisingly zippy for an old girl. She runs great, but needs a paint job badly. Gonna try to take her out tomorrow, if the weather holds. I'll try to get some pics.

 

[Fishing4Walleyes]

Re: 1958 3 hp Lightwin low speed idle

When you install the float there is a tab on the metal piece that sticks out. That tab needs to point towards the body of the carb and it seems that it prevents the float from dropping too far. If all you are working on is the float you can do that while the carb is mounted on the motor. It's a little easier than removing the carb.

 

[mikeaga]

Re: 1958 3 hp Lightwin low speed idle

Thanks for the info. Float is on order.

 

[1946Zephyr]

Re: 1958 3 hp Lightwin low speed idle

That float will work on 3hp's all the way up to the 7.5hp models. Just incase you have other oldies, this will be a pointer.

Yea, I hear ya kfa. I have a '59 Lone Star that needs a paint job too, but it'll be a nice fixer upper. It has a '59 RDSL-21B on it, that I'm in process of stripping down and restoring, now.