1960 10hp Johnson QD-21

[crashpro]

I just purchased a boat that has a 1960 10hp Johnson motor on it. I've been trying for two days to get it running, with limited success. I have new sparks plugs, new fuel tank, and new fuel. It takes 25-30 pulls to get it to start, and then will only start when the throttle is at the idle position. It won't even fire when it's choked and the tiller handle set at "start" position. If it's not set at idle, it won't even try to start. On the rare occassion that it does start, it will usually only run for about 10 seconds, then coughs and dies. I set the needle valves initially at 1 1/2 turns out and 3/4 turns out as I read on these forums. Once running, I adjust the appropriate needle valves to keep it running, again, as the forums have directed. At one time, I had it running for about 10 minutes and was able to accelerate (only extremely slowly) to full throttle. I adjusted the mid-high speed carb needle, idled back down and it was running like a sewing machine. Then it coughed and died and I was not able to get it to fire again the rest of the evening. I don't have a clue what to do from here.

 

[Joe Reeves]

Re: 1960 10hp Johnson QD-21

Assuming you have proper compression and spark, that leaves a fuel problem which is usually a fouled carburetor. Normally the cure is to thoroughly clean the carburetor.

(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.

 

[tx1961whaler]

Re: 1960 10hp Johnson QD-21

I would start by (in this order):
1. Checking the compression. Should be at least 60 psi, but more importantly, even readings across the cylinders.
2. Check the spark with a spark tester. Should easily jump a 1/4 inch gap.
If those are good, then look at the carb.

 

[crashpro]

Re: 1960 10hp Johnson QD-21

I appreciate the quick responses.I found a spark tester at O'Reilly Auto Parts. I'll let you know how that comes out. Is there a way to check the fuel delivery system? I saw a post where someone mentioned "o" rings on the fuel line. I've not noticed any. Are they on/in the male or female ends of the connection? I've also been looking for a carb rebuild kit, but have not been able to locate one as of yet. This motor has not been used on a regular basis for two years or so. Thanks!

 

[tx1961whaler]

Re: 1960 10hp Johnson QD-21

Carb kit is here at iboats:
http://www.iboats.com/mall/partfind...gd_poid=109333&gd_row=23&**********=632276708
O-rings are in the female side of connector.

 

[AlTn]

Re: 1960 10hp Johnson QD-21

I ran a piece of clear vinyl fuel line, O'Reilly's has it, from the fuel pump outlet to the carb to diagnose a fuel delivery problem on a QD-21 recently. As you pump the primer bulb you'll see fuel go through the pump and down to the carb, filling the carb until the needle shuts it off. Once the engine starts, you should see only fuel in the tube...no air bubbles. This test was done after establishing compression, spark, and fuel from carb to the cylinders. It's a finnicky adjustment on the carb, just use Joe's method as that go me goin'.

 

[kfa4303]

Re: 1960 10hp Johnson QD-21

Hi cashpro. I ahve the exact same motor and had similar issues bringing mine back to life. Turns out the dificult starting was due to bad points and condensres. I would highly recommend removing the flywheel and replaceing these parts while you're at it. Inspect the coils as well. They were famous for going bad on these older motors. Chances are they've already been replace by a previous owner, in which case they're probably fine, but do look at them and inspect them for any cracking or scorching. The points can/do accumulate corrosion over time, especially if its been sitting for a while, and while you can sand/file off the crud off it's easier to just replace them. You can get the points and condensers here at iboats as a "Tune up kit" for about $20. By replacing them you esentially replace the entire ignition system, whihc will ensure a strong, consistent spark for years to come. Make sure the points are gapped at .020" and the spark plug gap is at .030". Us Champion J6C plugs, or their equivalent, but nothing hotter these little motorss can't take the heat. Once you're sure you've got good strong spark, then worry about the carb. It's the easiest thing to adjust/fix and doesn't require removing the flywheel. Here are a couple of great links. Be sure to check out the Top Secret files in the forum. Lots of great info there too. Hope they help. Keep us posted. We love pics

http://www.outboard-boat-motor-repa...hnson 5.5 HP 1954-1964 Carburetor Tune-UP.htm --- Great site on how to clean and adjust your carb. It's not the exact same model as yours, but the basic ideas are the same.

http://www.sschapterpsa.com/ramblings/johnson_QD.htm ----- Great site for all around tune up.

http://www.marineengine.com/parts/v...ntage-evinrude-johnson/378459/37845900001.htm ----- Great parts diagram for any parts you may need.

 

[1946Zephyr]

Re: 1960 10hp Johnson QD-21

I would check the carb for any vacuum leaks. Make sure the gasket between it and the intake manifold is not leaking.

 

[crashpro]

Re: 1960 10hp Johnson QD-21

Well gentlemen, I found what the problem was. I checked the spark and it cleared a 5/16" gap, so OK there. I checked the compression, was 63 in both cylinders, so OK there too. Then I took a closer look at the tiller handle, and I'm ashamed to say what I found that I didn't notice before. Someone had removed the rubber grip, taken the indicator ring (says start, shift, fast, etc. on it), and reinstalled it backwards. When I thought I was trying to speed it up, according the speed indicator on the handle, it was slowing down. No wonder! I remembered a tiller motor that I had 30 years ago and it turned counter-clockwise to accellerate, while this one was indicating the opposite. I took it all apart, turned it around, and it now runs perfectly. Set up the carbs and it purrs like a kitten throughout the entire RPM range. Thank you all for the wealth of information was given to me. I'm sure I'll be back.

 

[crashpro]

Re: 1960 10hp Johnson QD-21

I tried twice to blow that stinking little gnat off of my screen. That's hilarious!

 

[1946Zephyr]

Re: 1960 10hp Johnson QD-21

Sweet