TOPIC: Operation Question for a '58 Johnson Fat Fifty

The previous owner rebuilt a lot of my Fat Fifty, and I've done some verifying of his work, but it still doesn't run right. He rebuilt the fuel pump, carb, and put new plugs in that I know for sure. I do know it needs the water pump rebuilt and fluid changed out yet, which I may find someone to take it to so that it gets done and maybe the rest of the engine is gone over while I work on the rest of the boat. I just want to make sure something else is wrong and it isn't just my operator error.

The way it is now, the only way to get it to start and stay running is to have it at least half throttle, and even then, I don't think it's running at that speed anyway.

With my pontoon, I just push the key in to activate the choke, turn it, and away I go. I always assumed I'd just push the choke button, turn they key, and away I'd go with this.

When disconnecting things to remove the engine the other day, I noticed a little white lever in the very front left corner of the engine, seen here in this pic just above the gas cap for the #3 gas tank:



This little lever has a start and run (or something like that) position. It appears that it had been in the start position. Does this lever need to be moved when starting, or is it overridden somewhere with the electric starting features?

Thanks!
Jon

The little knob/lever is nothing more than a manual speed control. It is only used to control the engine when the remote control throttle cable is unattached. So essentially, it now functions as a speed telegraph, sort of like to old ones in steam ships that told the engine room what speed the captain wanted to go. You just ignore it.

It may be that the carbureator was never set up correctly after service work. If it has the original carb, there will be a black plastic "pointer" knob on the top front of the carb. This controls the high speed main jets for the fuel. Flanking that control will be two little "thumb screws" sticking out at a 45 degree angle. One on either side of the carb. These are the idle adjustment screws. It is essential that all of these be adjusted correctly, and it isn't difficult to do. Pop open the carb access door on the engine hood. The should be a decal on the rear side of the door showing the user-controls on the carburator. Check this out to aid you in understanding what needs to be done.

Start with the idle "low speed" needle valves. Yours may or may not have little plastic or metal caps on each screw. These usually need to be removed to make the "rough " adjustment on these valves. Each screw (needle valve)should be fully removed from the carb body by turning it counter clockwise. Before doing this, get a wrench and slightly loosen the brass packing nuts at the base of each needle. Just loosen them slightly. Remove the needles. They are about 3" long when removed. The tip of them is pointed, much like a freshly sharpend pencil. The cone at the tip should be ecen, and free from ridges, ruts, or dings. If you have access to an air compressor, use a blow-tip to blast air into the needle valve openings where the needles were removed from. You should also insert a fine wire (single strand telephone company wire works great) straight into each needle opening. Try to thread the wire in the very center of each hole to get the wire to slip through the tiny holes at the bottom of each bore. This will push any crap out of the needle passages. Re insert the needdles by turning them clockwise untuil the bottom out. NO NOT tighten them - just lightly bottom them. Back each screw out 1-1/2 turns. Snug up the little brass packing nut at the base of each needle. NOT TIGHT!! The needles must be able to turn by hand with slight resistance. If the packing nuts are too thtight, the needles will not turn. Too lose & and they needles will suck air and lose adjustment due to vibration.

Try to run the engine & see if anything has changed. The fine adjustment of the low speed valves is a bit of an art. The fine tuning operation should not be attempted until the engine is fully warmed up. We can go over that later - if you get it that far.

About the main jets - probably can just do a very rough adjustment on those for now.

Move on to the main jets. pull up on the plastic pointer knob and swing it 180 dregees. Shis should disengage the knob from the main needle valves on either side. Turn the left and right needles CLOCKWISE untill they lightly bottom out. Then turn the needles counter clockwise 3 full turns. Return the black plastic knob to the original position.

Thank you Bruce! I will give this a shot and let you know. UPS says my new engine stand/cart will be here tomorrow, so I can get it on there and try running it from that. I did try putting the garden hose on it last summer, but is a big Rubbermaid garbage can sufficient to run it in?

I also have another issue that I've thought about taking it to a local guy who works on outboards for. I've heard these Fat Fifty's can have some raw gas going through the exhaust, but mine is a constant drip when it's running. I put a pan under it last year when it ran and it filled up the 12" square foil pan maybe 1/2" just from running for a minute or two. Any idea where this could be coming from? It isn't leaking from hoses on top. I need to replace the water pump both in this and the pontoon this winter, and I've never had a lower unit apart before- it's a little daunting.