1974 Johnson 9.9 Won't start

[Putzaroni1]

Re: 1974 Johnson 9.9 Won't start

Finally got back to it this afternoon and rigged up something to allow me to add fuel into the spark plug holes.
It fired right up. First pull it popped, second pull it popped and 3rd it fired up. So I'm guessing if I have 2 lbs of fuel pressure at the hose going into the carb but can't get fuel to the plugs, that must be the carb. I checked the choke and if I pull it out all the way it closes completely. So I'm guessing the next step is to pull the carb off again but this time pull the core plugs, soak everything and put wires through any holes ?

 

[Joe Reeves]

Re: 1974 Johnson 9.9 Won't start

Be sure to manually clean the high speed jet located at the extreme bottom nozzle end of the carburetor top body as I mentioned in reply post #5. Fuel must flow thru that jet before it can gain access to any other fuel passageway.

 

[oldboat1]

Re: 1974 Johnson 9.9 Won't start

sounds like the choke is working properly, at least (fully closed is fully choked, which would be achieved by pulling the choke lever/rod all the way out). It sounded from your post that you might be thinking differently about choke operation. I agree that it's the right move to get back into the carb, completely disassembling and soaking (other than the float), and cleaning with very fine wire. The plug on the top of the the carb should be removed, and the ports under there cleaned with cleaner and wire. If you pry out the plug carefully, you might be able to reuse it, but unlikely. It's also possible that one of the reed leaves is broken off. The reeds are just behind the carb -- good time to have a parts manual available (maybe a blowup online?). Unless you have done reeds before, you might want to try the carb cleaning first, and see if the motor runs like it should without any further fixes.

 

[Putzaroni1]

Re: 1974 Johnson 9.9 Won't start

Thanks a bunch.
I have the OMC kit for this carb including float so I'll take a run at it. I'm guessing I should soak it overnight in solvent, run the wire through the jets and passages, spray with carb cleaner and then blow everything out ? Once I've done that this week I'll put it back together and we'll see what happens........

 

[oldboat1]

Re: 1974 Johnson 9.9 Won't start

Sounds good. I use an old baking pan and lacquer thinner for soaking, then carb cleaner with the plastic nozzle. Guard skin and eyes, and keep a window open. Just for grins, you might check the size of that replacement plug in the kit before prying out the old one -- just to make sure the one in the kit will fit. It's a compression fit -- has to fit into the lipped opening, then seated in place with a tap from a hammer or hammer and punch of some kind. I use a small hammer and a short piece of metal dowel. good luck.

 

[Putzaroni1]

Re: 1974 Johnson 9.9 Won't start

I'll give that a try. I bought a pin punch set so I should be good to go.
One question, Can you see the reed valves when you pull the carb or do you need to remove the intake manifold as well ? I didn't see them when I pulled the carb off the first time.

 

[oldboat1]

Re: 1974 Johnson 9.9 Won't start

think you have to remove the inlet manifold, to which the carb attaches. There is a gasket between the manifold and the reed plate, and then another one behind the reed plate. You can do a partial check of the reeds after the inlet manifold is removed. If you can save the gasket under the inlet manifold, that could be useful -- try to carefully pry it from the manifold surface, leaving it attached (hopefully) to the face of the reed plate. You will be able to get a look at the reeds through the holes in the reed plate (two circles with about 8 holes each, or so). The reed leaves are shaped like petals of a flower, with a petal covering each of the holes in the plate. If one of the leaves is broken off, you will be able to see that. The reeds are attached to the backside of the reed plate, and the leaves should be perfectly flush against the holes. If the petals all seem to be intact and flat against the back of the reed plate, I would stop there and reassemble using some permalube to make sure the gaskets reseal. If you can get replacement gaskets, of course, you can use it/them in reassembly.

 

[racerone]

Re: 1974 Johnson 9.9 Won't start

There are 4 reed petals on a 9.9 ----------2 per cylinder.

 

[oldboat1]

Re: 1974 Johnson 9.9 Won't start

ah yes -- a "newer" model than the mid-50s to early 60s that I am probably thinking of. Racerone -- might be useful if you would provide inspection instructions for the '74 9.9, per Putzaroni1's request. All good stuff.

 

[Putzaroni1]

Re: 1974 Johnson 9.9 Won't start

Be sure to manually clean the high speed jet located at the extreme bottom nozzle end of the carburetor top body as I mentioned in reply post #5. Fuel must flow thru that jet before it can gain access to any other fuel passageway.

Thank you Joe. I have the carb apart and am about to put it in solvent for the night. All rubber and plastic has been pulled. I have attached 3 pictures that I have questions about. There are 2 core plugs I can see. One is larger and the second smaller.

My questions:

1) I assume I remove these 2 core plugs and that is it for removing plugs ?
a) What is under the larger one ?
b) What is under the smaller one ?

2) In the first picture, is the arrow pointing to the high speed jet ? Is this the one that needs to come out or do I have it out already ?

Thanks for your patience.... I'm getting there !

 

[Putzaroni1]

Re: 1974 Johnson 9.9 Won't start

I also noticed that the bowl was full of fuel so it's getting to the bowl, maybe just not past it which sounds like that high speed jet is plugged. I can blow through the jet and I poked a piece of wire through it and can see it in the wire come out the bottom into the carb chamber.

 

[raczekp1]

Re: 1974 Johnson 9.9 Won't start

under biger one is a chamber where fuel float(compresion from cylinder suck by 3 small holes at the bottom of this chamber )in at slow speed run from fuel bowl
smaller one is at air path, helping fuel flow from carb bowl

 

[AlTn]

Re: 1974 Johnson 9.9 Won't start

google..leeroy's ramblings and read his "ramblings" on 9.9/15 hp. carbs, in fact, read any and all on this series for a wealth of info and experience..if you don't have the jet removal tool get the best fit in your screwdrivers to remove that jet or main orfice plug, try not to chip or distort those slots. If it seems too hard to get out just clean it in place as best you can. Don't bend or break the metering tube that the jet supplies fuel to as that's the passage for mix entering the carb throat. The core plug on the top of the carb is the only one I've ever removed for cleaning purposes. While you have that core plug removed, reinsert you idle mixture needle to a gentle seat and you get an idea of how all that works. Reassembling, the tab on the float arm always points upward into the carb body. Float set is parallel to the carb body when inverted or the free end slightly higher than the hinged end. Slightly is like a 1/32 " or so, just visually higher. Ide mixture needle is out 1 and 1/2 turns from a soft set. Lynk and sync is shown in Leeroy's article. Post back with any other ?'s.

 

[Joe Reeves]

Re: 1974 Johnson 9.9 Won't start

My question: In the first picture, is the arrow pointing to the high speed jet ? Is this the one that needs to come out or do I have it out already ?

Yes, that is the high speed jet. The part number is 319016 and the inside diameter should be .051 . The number "51" should be imprinted upon the face of the jet indicating the ID size.

 

[Putzaroni1]

Re: 1974 Johnson 9.9 Won't start

So I'm reassembling the carb and the core plugs weren't as scary as I thought they would be. Pretty straight forward.
The carb soaked overnight in solvent, I rinsed it with soapy water and then hit it hard with carb cleaner through every hole I could find. Once I finished that I blew compressed air through all the holes and I can't imagine there's any dirt left in it.

I am almost finished with reassembly and two questions from installing the new float, needle, plug and washer.

2 questions:

1) I did the recommended blow test and it works but the needle sticks a little. When I blow it releases and opens. It's intermittent but it does happen just about every time. Probably not an issue but I thought I'd ask.

2) The little clip that comes on the carb kit that attaches the float to the needle. I think I read that it wasn't on the first 4 years of this style motor (74-78). Is it supposed to be used ? Would be be better if I did ? If so what do I attach it to ?

I see on the old needle it doesn't have the option to use one but on the new one there is a cut out at the top of the needle to allow you to attach it.

Thanks for your thoughts. You guys are the best !

 

[oldboat1]

Re: 1974 Johnson 9.9 Won't start

good job. The second time will be a cakewalk. I can't address your question about the needle, but recommend that you attach the little clip that came with your kit. It attaches to the top of the needle as you surmise, and the other end (long part of the clip) slips over the arm that holds the float, just above the needle. (In my opinion, the sticking needle just shows you that it is seating well, and isn't an issue. But other listers may have other opinions on that.) Good luck.

 

[OptsyEagle]

Re: 1974 Johnson 9.9 Won't start

Use the little clip. It is designed to ensure that the needle does not stick. When pressed up by the float the needle will create a great seal and when pulled down that spring will ensure the needle opens the valve up for fuel to flow. You really don't want an intermittent sticking of that needle.

 

[Putzaroni1]

Re: 1974 Johnson 9.9 Won't start

Update !!

So it's 45 degs Fahrenheit today and sunny ! Gotta love the Pacific Northwest (sorry for bragging !)

It did give me a chance to get outside and fill a garbage can with water and try this motor out.
Took a bit to get it going (10 or 15 pulls, choke or no choke) but once it started and ran for a bit it seemed to want to stay running pretty good. When I tried turning the idle down it would idle fine for up to a minute or 2 and then make a pop sound and stall.

I'm going to try Joe Reeves method again for setting the idle but I think I did pretty much already. If I give it just a bit more than slow idle throttle it seems to run for as long as I like. Also tested shifting and it's working well both forward and back. I did not end up doing anything with the ignition yet and may not have to if it's working.

More to come and again, thanks all for our input. I have learned a ton on this motor, purchased some tools and it motivated me to buy a couple more motors that don't run.

Is this a common behavior for iboat forum followers ;-)

 

[tomhath]

Re: 1974 Johnson 9.9 Won't start

I have learned a ton on this motor, purchased some tools and it motivated me to buy a couple more motors that don't run.

Is this a common behavior for iboat forum followers ;-)

Only a couple of motors? That's uncommon...

There's an idle speed adjustment knob on the side of the motor, all it does is hold the throttle open a little (you need to loosen the set screw to turn it). The motor should idle around 600 RPM when it's running in water and in gear. A "Tiny Tach" is another useful tool that doesn't cost too much, but you can just set it to a reasonable idle speed without one. It'll idle kind of fast in neutral when it's set to the right speed in gear.

 

[OptsyEagle]

Re: 1974 Johnson 9.9 Won't start

In setting the idle, I assume you are talking about the slow speed carburetor adjustment. Just use Joe Reeves method. I would assume the pop you mentioned was the sign that you had it too lean. If so, I would just turn the knob about a 1/4 turn counter-clockwise and leave it.

The other thing you need to do or ensure is that your link and sinc is set. You should observe that as you turn the throttle a little metal piece (throttle cam) will come up and touch the roller on the carb. On that throttle cam is a line or an arrow. When that cam just touches the roller, that arrow should be directly in the center of the roller. This ensure the proper spark timing for your motor across all RPM ranges, including idle. If it is not set right, there are two hex nuts on the starboard side under the flywheel that can be loosened to set this. This link and sinc is designed to set the timing advance. Setting your timing advance has an effect on starting, higher speed performance and idle. You will notice as you reduce the idle on a running motor that the throttle cam eventually comes off the carb's roller completely. So even with the carb butterfly completely closed, the timing advance allows you to reduce idle even more, so obviously if you are having idle issues, you want to verify that this is set correctly.