72 Evinrude 18202 - wont low idle, hiccups and dies at half choke

[Total Basshole]

I have been trying to get this motor working with minimal knowledge of motors in general. It sat in the water on a desert lake for a few years unused. I have replaced the plugs, checked the fuel pump/filter(looks fine), changed the lower unit oil and rebuilt the carburator. The motor starts on the first pull and runs ok on high idle, but it will not run at low idle, it just sputters out and dies (if it matters cooling system seems to be working, plenty of water discharge). The motor starts and runs with the choke butterfly just barely open (choke almost all the way out). When you try to open it any further(push choke in) the engine seems to cough, sputter and die every time the butterfly passes halfway. I have tried running it at high idle for several minutes to warm up the engine, but I still have the same problem with the air intake when I try to open the butterfly all the way.

Can anyone give me an idea of what might be the problem? I have reached the small limit of my knowledge on motors. Thanks in advance,

 

[F_R]

Re: 72 Evinrude 18202 - wont low idle, hiccups and dies at half choke

Back to the carburetor, my friend. You missed something. Did you inspect the high speed orifice plug in the very bottom? It must be absolutely clean. In addition to that, it sounds like there may be a problem in the idle circuit. You need to take another look.

 

[Total Basshole]

Re: 72 Evinrude 18202 - wont low idle, hiccups and dies at half choke

Thank you for the reply. As I said I really have no experience with this so I checked the parts diagram of the carb to see what part your talking about. I do not remember there being a plug besides the drain plug in the bottom of the carb when I took it apart. I am guessing it was missing to begin with. I was very careful not to drop or lose parts. Looks like I need part #45.

http://www.marineengine.com/parts/j...202R&manufacturer=Evinrude&section=Carburetor

Also what is the idle circuit?

Thanks again

 

[F_R]

Re: 72 Evinrude 18202 - wont low idle, hiccups and dies at half choke

Uh huh, that means the answer is no, you didn't examine the orifice plug. It cannot run without it, so let's assume it is in there, or it wouldn't have ran last time it was used (old joke). It meters all the fuel that the engine burns. Too large and it runs too rich, too small (or dirty) it runs too lean.

The idle fuel also goes through that orifice plug, then up through various drilled passages to the area of the slow speed needle, then through tiny holes into the carb throat. That is the "idle circuit". Part way through the idle circuit is part #35 "bearing", which actually is a seal. If it is shot, air leaks into the idle circuit. Before you tell me it isn't in there either, yes it is. But da** near invisible once installed.

Be sure #40 gasket is in place and not leaking.

 

[Total Basshole]

Re: 72 Evinrude 18202 - wont low idle, hiccups and dies at half choke

I have no idea if the motor did run last time it was used. The seller was not able to give much history on it besides an ex of hers got it and put it on her boat. In taking it apart, it looks a lot like someone tried to get it working. The fuel pump and filter were new, the carb and all the parts were clean, just the gaskets were old. Even the float looked relatively new. My speculation was that someone did a lot to get it working but never finished the job. I cant guarantee they put all the parts back together correctly. I did pop off all the plugs and inspect all the passages for blockages and I dont remember the plug. Would the motor not even start without the orifice plug? If that is the case then it is there and I am proving my previously stated inexperience.

I did find the old bearing on the needle valve but now I think I put it back together incorrectly. The carb repair kit instructions dont show any type of gaskets or seals around the bearing, but there are 3 small rubber o-rings in the kit that I was not able to figure out and I didnt see anything like them in taking it apart. Now I am thinking they might hold the bearing in place and help make the seal airtight? That would mean I need to pop off the core plug and put the bearing on correctly with the o-rings once the needle valve is rethreaded. Neither the carb repair kit instructions or the parts diagram show the o-rings position. Do the rubber rings go on both sides of the bearing? Is there another piece I am missing? Again sorry for my ignorance, but i really appreciate the help.

 

[F_R]

Re: 72 Evinrude 18202 - wont low idle, hiccups and dies at half choke

No o-rings in there that I can think of. The bearing goes in the slow speed needle hole, small end in first, and pushed all the way to the bottom.

"It ran the last time it was used" is an old laughing matter. Of coarse it ran or it couldn't have been used.

But no, it won't run without the orifice plug. It would flood like crazy.

 

[Total Basshole]

Re: 72 Evinrude 18202 - wont low idle, hiccups and dies at half choke

ok i just pulled the carb and the oriface plug is there after all. i pulled it out and it looks clean throughout.

i also pulled out the needle valve. one problem now is that i think the old rubber bearing is stuck in the screw hole.
how do i get that out?

the new plastic one from the kit looks like it will break when i try to thread the needle.

 

[F_R]

Re: 72 Evinrude 18202 - wont low idle, hiccups and dies at half choke

I made myself a special tool for removing the bearing. Some people have told me they remove it with a drywall screw, I have never tried it, but sounds like it might work. Others use a crochet hook that they "borrow" from their wife.

Break?? The bearing or the retainer? Neither should break.

 

[Total Basshole]

Re: 72 Evinrude 18202 - wont low idle, hiccups and dies at half choke

i used a wooden bbq skewer to get it out. getting the new bearing started was a little troublesome but i tapped the end of the needle screw with a hammer and it seated far enough for the screw to grip. i think its installed correctly. seated gently and backed out a quarter turn. i popped off the core plug cause i needed the light to pass through to be sure i had all the old bearing so as soon as i get a new cap i can retest the motor and see if it makes a difference. thanks. thats all for now.

 

[Total Basshole]

Re: 72 Evinrude 18202 - wont low idle, hiccups and dies at half choke

I tried redoing the needle valve bearing and im still getting the same issue. High idle runs fine but try to low idle and it hiccups and stalls. Try to open the choke more than 1/2 and it hiccups and stalls. Starts on first pull every time and when it is in high idle it sounds great and runs smooth.

I pulled the oriface plug and its totally clean. The whole carb and all the chambers are clean. All the gaskets are plugs are in place. Is there anything besides the carb that could be causing this issue? I feel like I am so close to a water test its killing me not to know what I need to do to fix it.