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orphaned 1962 FD-16

A

AllenH59

New member
Gentlemen. I am owner number 3 of this engine that will not run well. I have done the tests on the coils, and the plug wires, set the points, taken the carb apart to the extent of ensuring the float does close the needle valve, the carb was rebuilt by one of the previous owners. It sparks perfectly on both plugs, with them out of the engine. I can get it to idle, although it idles with a bit of a miss, but when I try to rev it up it quits, independent of where the high speed jet is set. I have tried all the suggestions on the net. It has lots of compression on both cylinders, and by looking at the plugs, it certainly is running on both. the fuel pump nicely fills the sight glass. Any ideas? thanks
 
But does the spark actually jump a gap of 5/16" , yes or no ?---------And perhaps the throttle is opening too soon.
 
So you have done tests on the coils. We get that. But tell us, how do they look? Are they cracked or all dried-up looking? If they are, it may have spark and may run a bit, but never right until you replace them
 
1962 18hp Johnson FD-16

Spark plugs should be Champion J6c plugs gaped at .030.

What are the actual psi compression readings of both cylinders?

There is a scribe mark on the cam that slides against the carburetor throttle roller. The throttle butterfly should just start to open when the scribe mark is dead center with that roller... not before or after.

The spark, with the s/plugs removed, should jump a 1/4" air gap with a strong blue lightning like flame... a real SNAP! Does it. Note that the gap is important!

********************
(Spark Tester - Home Made)
(J. Reeves)

You can use a medium size philips screwdriver (#2 I believe) inserted into the spark plug boot spring connector, then hold the screwdriver shank approximately 7/16" away from the block to check the spark or build the following:

A spark tester can be made with a piece of 1x4 or 1x6, drive a few finishing nails through it, then bend the pointed ends at a right angle. You can then adjust the gap by simply twisting the nail(s). Solder a spark plug wire to one which you can connect to the spark plug boots, and a ground wire of some kind to the other to connect to the powerhead somewhere. Use small alligator clips on the other end of the wires to connect to ground and to the spark plug connector that exists inside of the rubber plug boot.

Using the above, one could easily build a spark tester whereas they could connect 2, 4, 6, or 8 cylinders all at one time. The ground nail being straight up, the others being bent, aimed at the ground nail. A typical 4 cylinder tester follows:

..........X1..........X2

.................X..(grd)

..........X3..........X4
*****************

(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.
********************
(Point Setting Of Magneto Models)
(J. Reeves)

Note that there are other ways to set points such as using a ohm meter or timing light... however, the following will result in a setting so close to being exact that one could not tell the difference.


Make sure that your feeler gauge is absolutely clean so as NOT to transfer oil/grease to the points.

Set the points as follows. Have the flywheel key aligned with the fiber rubbing portion of the ignition points. Adjust the gap so that a .020 gauge will pass thru but a .022 will not. Should there be any question of the points being dirty (touching the contact with your finger would cause them to be dirty), clean them with a small brush and acetone or lacquer thinner.

NOTE 1: Should the operating cam have a small portion on it with the word "SET" imprinted, align this portion with the fiber rubbing portion instead of the flywheel key.

NOTE 2: Should the cam have the word TOP embossed on the top of it, that is a cam that could be installed upside down and this is simply telling you which side is up. It is not a position where one would set the points.

********************
(Carburetor Float Setting)
(J. Reeves)

With the carburetor body held upside down, the float being viewed from the side, adjust the float so that the free end of the float (the end opposite the hinge pin) is ever so slightly higher (just ever so slightly off level) than the other end. And when viewed from the end, make sure it is not cocked.

********************
(Magneto & Driver Coil Alignment)
(J. Reeves)

To align the coils properly, have the metal vertical portion of the coil yokes aligned with the inside edge of the bevel that exists on the top portion of the aluminum seat upon which the coils sit. This creates the proper distance between the coils and the flywheel magnets. Faulty alignment creates friction and the yokes of the coils heat up, turn blue and expand.
 
Last edited:
fdrgator said:
So you have done tests on the coils. We get that. But tell us, how do they look? Are they cracked or all dried-up looking? If they are, it may have spark and may run a bit, but never right until you replace them
Click to expand...

Thanks for the tips, I will build a spark tester, the coils look new, there is no cracking or distortion of the surfaces, the float may be a little high if anything, as it is horizontal if the carb is upside down, The points are clean, and gapped correctly. I am reasonably mechanical, (this stuff is not superstition to me), and I am old enough to know that running is a combination of fuel/air/compression/ignition and timing... It runs for a short time and quits, leading me to believe it is a fuel problem. Sitting here the only thing electrical I can think of is that the last guy cut the wires quite short on the condensers, and crimped on connectors, I guess if one of those connections is bad.... I removed to points to inspect them, and they were both slightly burnt, I cleaned them up, and ensured they met correctly. I have a machine shop, (lathe, mill etc, and can measure) I will determine just how far the spark jumps, it was nice and blue in the fading daylight on the spark plugs. I am not going to give up on this engine, and while I do not wish to just throw parts at it, it will get what it needs.
 
racerone said:
But does the spark actually jump a gap of 5/16" , yes or no ?---------And perhaps the throttle is opening too soon.
Click to expand...
yes, 3/8" of spark, no the throttle is not early or late.. had the fly wheel off it, there is a bit of play in the magneto plate, just enough I could feel it.
 
fdrgator said:
So you have done tests on the coils. We get that. But tell us, how do they look? Are they cracked or all dried-up looking? If they are, it may have spark and may run a bit, but never right until you replace them
Click to expand...
The coils look new, they are green, which I presume means they are after market, but anyway, they look new, as I said in another reply, there is a small amount of movement in the magneto plate, just enough that I can feel it. I guess there has to be a little movement so it can turn.
 
I had the flywheel off it, everything looked ok, gap was correct, plugs were a couple thousandths tight, I fixed that. I do not have a compression gauge, however, there is lots of compression even when turned over with a wrench at low speed. I set the high and low speed jets as directed, still runs the same. I lowered the float a little as well.


joereeves said:
1962 18hp Johnson FD-16

Spark plugs should be Champion J6c plugs gaped at .030.

What are the actual psi compression readings of both cylinders?

There is a scribe mark on the cam that slides against the carburetor throttle roller. The throttle butterfly should just start to open when the scribe mark is dead center with that roller... not before or after.

The spark, with the s/plugs removed, should jump a 1/4" air gap with a strong blue lightning like flame... a real SNAP! Does it. Note that the gap is important!

********************
(Spark Tester - Home Made)
(J. Reeves)

You can use a medium size philips screwdriver (#2 I believe) inserted into the spark plug boot spring connector, then hold the screwdriver shank approximately 7/16" away from the block to check the spark or build the following:

A spark tester can be made with a piece of 1x4 or 1x6, drive a few finishing nails through it, then bend the pointed ends at a right angle. You can then adjust the gap by simply twisting the nail(s). Solder a spark plug wire to one which you can connect to the spark plug boots, and a ground wire of some kind to the other to connect to the powerhead somewhere. Use small alligator clips on the other end of the wires to connect to ground and to the spark plug connector that exists inside of the rubber plug boot.

Using the above, one could easily build a spark tester whereas they could connect 2, 4, 6, or 8 cylinders all at one time. The ground nail being straight up, the others being bent, aimed at the ground nail. A typical 4 cylinder tester follows:

..........X1..........X2

.................X..(grd)

..........X3..........X4
*****************

(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.
********************
(Point Setting Of Magneto Models)
(J. Reeves)

Note that there are other ways to set points such as using a ohm meter or timing light... however, the following will result in a setting so close to being exact that one could not tell the difference.


Make sure that your feeler gauge is absolutely clean so as NOT to transfer oil/grease to the points.

Set the points as follows. Have the flywheel key aligned with the fiber rubbing portion of the ignition points. Adjust the gap so that a .020 gauge will pass thru but a .022 will not. Should there be any question of the points being dirty (touching the contact with your finger would cause them to be dirty), clean them with a small brush and acetone or lacquer thinner.

NOTE 1: Should the operating cam have a small portion on it with the word "SET" imprinted, align this portion with the fiber rubbing portion instead of the flywheel key.

NOTE 2: Should the cam have the word TOP embossed on the top of it, that is a cam that could be installed upside down and this is simply telling you which side is up. It is not a position where one would set the points.

********************
(Carburetor Float Setting)
(J. Reeves)

With the carburetor body held upside down, the float being viewed from the side, adjust the float so that the free end of the float (the end opposite the hinge pin) is ever so slightly higher (just ever so slightly off level) than the other end. And when viewed from the end, make sure it is not cocked.

********************
(Magneto & Driver Coil Alignment)
(J. Reeves)

To align the coils properly, have the metal vertical portion of the coil yokes aligned with the inside edge of the bevel that exists on the top portion of the aluminum seat upon which the coils sit. This creates the proper distance between the coils and the flywheel magnets. Faulty alignment creates friction and the yokes of the coils heat up, turn blue and expand.
Click to expand...
 
bobbyc said:
Does manually "choking" it help when it loses power???
Click to expand...
I took apart and reconnected the condenser connections. (some previous wiz had cut the end off the wires and crimped on connectors to make them shorter,)
This made it run. Now it is not pumping water....
 
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