Seahorse 18hp - It's running! Onto the next problems....

stjon

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Thankyou all who have replied to my various questions to date - my Johnson now runs and I am SO happy!! I have replaced the coils, checked the condensors, and finally removed and cleaned the points so I got two good sparks - there really is no short cut is there?! But still a non runner so I moved onto the carb - cleaned it all out and found the float bowl needle was sticking - I know I really should have bought a carb kit but its a major hassle obtaining parts in the UK, so just used lots of carb cleaner and now it only sticks if pushed in hard. So now she runs (rough) and I have learned a lot already.

I've read there is no telltale water outlet so I'm a bit nervous that she is being cooled properly - the thermostat cover became too hot to touch after a couple of minutes so I shut her down. How can I be sure there is water circulating? I plan to change the impeller anyway as a precaution but I would like to understand what's happening. I have a problem with the gearchange connector coming loose at the bottom link, so it was stuck in gear and I couldn't see anything in the water other than turbulence and exhaust gas.

Apologies for the following poor description, but when I was reassembling the carb I noticed that the lean/rich dial on the rear moves (via a bar) a spindle that enters the top of the carb. When this spindle is disconnected from the lean/rich dial, the spindle seems to spin freely inside the carb - is this correct?
 

HighTrim

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Re: Seahorse 18hp - It's running! Onto the next problems....

What model are we talking about here?

You should get a mixture of water out of the exhaust port with the exhaust gas. It should be quite noticable. If there is nothing there, stop running until you change the impeller. The water line should come up a few inches below this port in the barrel if you are running it in your driveway.
 

stjon

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Re: Seahorse 18hp - It's running! Onto the next problems....

Sorry! It's a Johnson Seahorse 18hp model no. FDL - 19D. I'll try to get it into neutral and run it again so hopefully I can see more of what's going on.
 

kfa4303

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Re: Seahorse 18hp - It's running! Onto the next problems....

Hi stjon. Great old motor you've got there. Based on the model number it's a 1965, which was the last year Johnson made the 18 hp, I believe. I have a 1966 model which was the first year of the 20 hp which is virtually identical. Here area few links that can walk you through a tune up from top to bottom. However, these old gems can't be run on modern cooling "muffs", so be sure you only ever run the motor int a test tank with water filled to within 1-2 of the main exhaust port of the back of the motor. You'll also want to run at least 50:1 mix, although I run 24:1 in mine without issue. Champion brand spark plugs are best as well. You'll want you use either J4C or J6C plugs. The basic starting procedure is to open the vent on the fuel tank, prime the fuel line with the squeeze bulb until firm, pull out the choke on the motor, advance the throttle to its farthest setting while in neutral, then pull to start. Once the motor fires, you will then need to push the choke lever back in and let it assume a nice idle. Don't be alarmed by the amount of smoke and/or oil gunk in the test tank water. That's perfectly normal. They don't call them "2 smokes" for nothing. Once it is in good running order, it should push most 14' boat +20 mph. Good luck. Holler if you get stuck.

Maintaining Johnson E & FD Serie

Vintage Evinrude Johnson Outboard Parts & Diagrams - Catalog 404157

http://forums.iboats.com/engine-fre...sorted-carb-variations-joe-reeves-167352.html

1958 Johnson 18 HP outboard - Running - YouTube (I would fill the water a little than seen in this vid, but it's a nice idling motor all the same)

1968 Evinrude Fastwin 18HP - YouTube

Johnson 18 hp 1963 - YouTube

1966 Johnson FD-20C, 20hp outboard on a 1959 Arkansas Traveler DUT-14 aluminum runabout - YouTube (here's my boat and motor) (sorry the music so loud :) )
 

stjon

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Re: Seahorse 18hp - It's running! Onto the next problems....

What a reassuring post - thanks! I got it into neutral and ran it again - I saw a good stream of water when I revved it up, so that sounds good? Also a lot of smoke and gunge in the water - I'd assumed this meant my bottom end might be letting water in? I'll check and see what the oil looks like anyway. It's currently idling very lumpily - can anyone advise on the lean/rich question I posed above?
 

HighTrim

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Re: Seahorse 18hp - It's running! Onto the next problems....

Is the "spindle" that you refer to the needle? It should turn, but not freely. If too loose, it will run lean due to an air leak. Tighten down the packing nut to snug things up. If still loose, more packing is required.

It should be at about 1.5 turns out from lightly seated. Then fine tune on the water.
 

kfa4303

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Re: Seahorse 18hp - It's running! Onto the next problems....

Hell again stjon. The waterflow is a great sign. That means your water pump(aka impeller) is working correctly. Unfortunately, these older motors don't have a "pee stream" like modern motors, but instead eject the cooling water along by combining it with exhaust gases and expelling out of the back of the motor. Don't worry about the grungey water either, that's also normal. Don't worry it won't be anywhere near as bad on the open water. The problem is amplified while in a test tank because you keep recycling the same water over and over. If you're worried about the gear oil, you can open the large flat head screw labeled DRAIN on the lower unit a few turns. (Do no touch the Phillip's head (cross head in UK?) If the oli comes out a clear/honey, or even blackish/grey colored it's fine. However, if comes out looking milky/white, then you do have water intrusion. Not to worry, resealing the lower unit is a job you can do yourself, if need be, but hopefully that won't be necessary. As for the idle, I'll post a link below. Per the previous post, the idle adjust screw (aka lo speed needle) should be firm while still being loose enough to allow for small adjustments. Rotating the needle inward, leans the mix and should raise the rpms, while backing the needle out will richen the mix and lower the rpms. There is also and idle set screw found at the base of the tiller arm that is used to adjust the idle by advancing or retarding the timing slightly. By finding a balance between the two, a nice idle can be dialed in with a bit of patience. As you've seen, the motor does smoke quite a bit while in a test tank. As a result, some people will set up a small fan to help blow it away to insure that the motor has plenty of clean air to take into the carbs. Don't worry the smoking will decrease greatly once you're at speed on the water. I run my '66 20 hp 24:1 and it only smoke upon start up, then runs nice and clean for the rest of the day. Good luck!

http://forums.iboats.com/engine-fre...sorted-carb-variations-joe-reeves-167352.html
 

stjon

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Re: Seahorse 18hp - It's running! Onto the next problems....

iboats2.jpgIboats1.jpg

OK I've tried to upload 2 pics - hope that has worked. The first shows the nut that screws into the float bowl at the base - from looking at the parts listing on MarineEngine.com for a 1959 motor, I expected this to be the high speed needle, but it's actually just a bolt with a dead end? The second pic shows the slow speed needle removed, and I think I know now why this was turning freely - there appears to be a aluminium coloured bush stuck to it that I suspect shouldn't be stuck to it! Have I got a problem?
 

stjon

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Re: Seahorse 18hp - It's running! Onto the next problems....

Edit - the upload worked but the pics are reversed - sorry for any confusion.
 

stjon

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Re: Seahorse 18hp - It's running! Onto the next problems....

Grrr - another edit. I am stupid - just clicked kfa4303's great link to a 1965 catalogue and clearly the bottom screw is now a simple plug and not a needle. Sorry about that.
 

kfa4303

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Re: Seahorse 18hp - It's running! Onto the next problems....

As you've discovered stjon, the lower needle is fixed on the later FD models, however they used to be adjustable on previous versions. The low speed needle looks to be in good shape, but it's missing the packing washers which create and air tight seal and allow for fine adjustments. The packings are simple, brownish-red fiber washers that come in every carb kit. You will need to install 2-3 between the brass nut and the small silver-colored bearing the low speed needle threads into. See link below for a better description. Once the installed, you should be able to dial in a nice low idle using the previously posted link.
Here's a great caburetor rebuild link. It's for a slightly different model, but the procedure is the same. That's half the beauty of these old OMC (Johnson/Evinrude/Gale) motors, once you can fix one, you can fix them all. Pay special attention to the section regarding the packing needles about 2/3 way down the page.

5.5 HP Evinrude Johnson 1954-1954 Carburetor Tune-Up Procedure
 

stjon

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Re: Seahorse 18hp - It's running! Onto the next problems....

Thanks as always kfa403. So the silver bush is what the needle actually screws into?! So I take it am safe to (carefully) grip the silver bush and unscrew the needle?
 

HighTrim

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Re: Seahorse 18hp - It's running! Onto the next problems....

Yup. They bushing goes in first, followed by 2 or 3 packing washers. I then thread the packing nut in, not fully, just snug, and then seat the needle, back it out 1.5 turns, then fully tighten down the packing nut. It is a bit of back and forth sometimes to get the packing nut tight enough to keep the bearing from free spinning, yet having it loose enough to be able to adjust the needle.
 

kfa4303

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Re: Seahorse 18hp - It's running! Onto the next problems....

Sure you can unscrew it. Then place the bearing back into the carb. You then slide 2-3 packing washers over the tip of needle and thread the needle into the bearing. You then slide the brass nut over the needle and snug it down such that the idle needle has enough friction to stay where you leave it. There is also sometimes a small black, plastic washer that goes between the brass nut and the brown packings to prevent them from being damaged. Follow the procedure in the link below for dialing in the carb. Once you have the motor on the open water, you can snug the brass nut down a bit more and the needle shouldn't move at all despite the engine vibrations. Hang in there. You're almost there!

http://forums.iboats.com/engine-fre...sorted-carb-variations-joe-reeves-167352.html
 

stjon

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Re: Seahorse 18hp - It's running! Onto the next problems....

I am a little unclear about the procedure here - when I've removed the silver bush from the needle, do I just push fit the bush inside the carb body until it sticks tight? Then the packing washers, then the needle screws into the bush? Is that correct? Thanks for your patience!
 

stjon

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Re: Seahorse 18hp - It's running! Onto the next problems....

Forget my last post! Just seen your replies guys - thanks as always.
 

kfa4303

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Re: Seahorse 18hp - It's running! Onto the next problems....

yes, remove the bushing and place it back into the carb, then slip 2-3 packings over the tip of the needle then thread the needle into the bearing until gently seated, then slide the brass nut over the opposite end of the needle and thread it a few turns. The more you tighten the brass nut down, the harder it should be to adjust the idle needle. By twisting the idle needle in, it should lean the mix and raise the rpms, backing it out should fatten/enrich the mix and lower the rpms.
 

stjon

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Re: Seahorse 18hp - It's running! Onto the next problems....

I have replaced the slow speed needle as guided above - thanks. Need a decent day to get it in the barrel again to test that. Removed the lower oil drain plug and thick milky cream oozed out - water intrusion I assume....so that's the next job!
 
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