Page 2 of 3
Re: Lack of power in a 184
Posted: Thu Mar 08, 2012 2:20 pm
by RaymondDurban
If I'm reading this correctly, you set high idle (as much as you could get) at 16* BTDC, but when you retard the throttle it stays at 16*? This should not happen and it leads me to believe that the weights in the distributor are stuck, not allowing the advance function built in to work as it should.
For the low idle, there is a screw on the back side of the carb on the throttle shaft. As you back the screw out, it allows the butterfly to close reducing the fuel allowed into the combustion chamber which slows the engine. This is the easy fix.
For the high idle (full throttle-no load), there is a bolt on the top side of the governor that limits the travel of the governor rockshaft, which limits the movement of the throttle shaft in the full throttle position. Before you mess with this adjustment, set the low idle on the carb and repair what is necessary inside the distributor to allow the advance function to work.
After the advance is working, then check the timing and RPMS again, both low and high idle. If it is still low, you can adjust the bolt on the governor to allow the high RPMS to increase to the desired setting.
Re: Lack of power in a 184
Posted: Thu Mar 08, 2012 3:45 pm
by Dieselrider
RaymondDurban wrote:If I'm reading this correctly, you set high idle (as much as you could get) at 16* BTDC, but when you retard the throttle it stays at 16*? This should not happen and it leads me to believe that the weights in the distributor are stuck, not allowing the advance function built in to work as it should.
For the low idle, there is a screw on the back side of the carb on the throttle shaft. As you back the screw out, it allows the butterfly to close reducing the fuel allowed into the combustion chamber which slows the engine. This is the easy fix.
For the high idle (full throttle-no load), there is a bolt on the top side of the governor that limits the travel of the governor rockshaft, which limits the movement of the throttle shaft in the full throttle position. Before you mess with this adjustment, set the low idle on the carb and repair what is necessary inside the distributor to allow the advance function to work.
After the advance is working, then check the timing and RPMS again, both low and high idle. If it is still low, you can adjust the bolt on the governor to allow the high RPMS to increase to the desired setting.
Okay, I tried to adjust the carburetor low idle screw for the low idle stop (hoping that is what you are referring to) and more then just a slight backing out of that screw shuts the motor down. Can restart if I choke and place in fast idle but, as soon as is slowed down to low idle, it shuts off.
The weights you mention, are they in the distributor or inside the governor? I have had the distributor off in the past and I do not remember any weights in it? I'll refer to the manual to see if I can determine what you are telling me. Thanks.
Re: Lack of power in a 184
Posted: Thu Mar 08, 2012 4:39 pm
by RaymondDurban
Ok, if backing the screw out kills the engine, then it's either the timing killing the engine or lack of fuel. Reset the timing to around 8* (approximately half way between the low and high marks) for the time being. Then retry backing out the screw and see if the engine still stalls. If it does, then your Carb will also need going throuh, with particular attention to the idle circuit (passages).
Here is a page from the manual that you can see the distributor weights (item 14):
http://www.cleancomputes.com/Cub/Cub%20Parts%20Manuals/TC-37F%20Revision%206%20(08-79)/Group%20-%2012%20-%20Power%20-%20C-60%20Engine/Page-28.jpg
Re: Lack of power in a 184
Posted: Thu Mar 08, 2012 5:02 pm
by Dieselrider
How do you get to the weights in the distributor? I also have no idea what I am doing with a carb. (I so like diesels). I know I can find the main components of the carb but, I am not even sure what passages should be where let alone how to clean them out. I have some dental picks and such from the tool and die trade. Will they work? Thanks.
Re: Lack of power in a 184
Posted: Thu Mar 08, 2012 5:08 pm
by Bob McCarty
Dieselrider, Where are you located? There maybe someone close by that can help with the carb, or a Cubfest that you could also attend.
Bob
Re: Lack of power in a 184
Posted: Thu Mar 08, 2012 6:13 pm
by Dieselrider
Bob McCarty wrote:Dieselrider, Where are you located? There maybe someone close by that can help with the carb, or a Cubfest that you could also attend.
Bob
Thanks, Bob. I am in West central PA (Southern Clearfield County) I don't usually have a lot of time in the summer months as we run a CSA (community shared agriculture) here where we sell vegetable shares to clients as well as pork, beef, chicken and eggs so, summer is pretty busy. That is why I am trying to work on it now. However, if I could get somewhere with it and get someone to show me the ropes, I would greatly appreciate it. I am not a mechanic but, I am (I believe) fairly mechanical. I just don't have the experience and these have a lot of adjustments that could be out. I think once I had seen or been shown the how, I could then do what is needed. Is there a Cubfest anywhere close? A member, perhaps? Thanks again.
Re: Lack of power in a 184
Posted: Thu Mar 08, 2012 8:53 pm
by Dieselrider
That wasn't so bad. I pulled the distributor off, took it all apart, cleaned it up (those weights were rusted but, I don't know that they were seized up or anything- you could move them with a screw driver- probably dragging some ), then reassembled everything and put a bit of oil on everything. I'll warm it up tomorrow and reset the timing and see if that makes any difference in the advancing of the timing. Thanks.
Re: Lack of power in a 184
Posted: Thu Mar 08, 2012 9:36 pm
by RaymondDurban
Were the springs still attached and in good shape?
Re: Lack of power in a 184
Posted: Fri Mar 09, 2012 12:33 am
by Jim Becker
Try stastic setting the advance at 0 degrees. Then start the engine and check it at fast idle. Your current low idle is so low HIGH that the distributor may already be fully advanced at low idle.
Edited as shown.
Re: Lack of power in a 184
Posted: Fri Mar 09, 2012 6:39 am
by Dieselrider
RaymondDurban wrote:Were the springs still attached and in good shape?
Yes the springs were still attached and rusty but still have "springy ness". I cleaned them up with a small wire wheel on a Dremel tool as well as the other parts and put a little oil on everything to help it stay clean.
Re: Lack of power in a 184
Posted: Fri Mar 09, 2012 6:45 am
by Dieselrider
Jim Becker wrote:Try stastic setting the advance at 0 degrees. Then start the engine and check it at fast idle. Your current low idle is so low that the distributor may already be fully advanced at low idle.
"low idle is low"? According to the book, it should be at 600 rpms and mine is saying 1350 (and it varies from 1200 to 1380). Now, I have no idea just how accurate this digital tach. is. It is a cheap unit and I don't know what could be used to test it. Perhaps an electric motor that is supposed to turn at a certain rpm? Then how will I know the motor is accurate?
Re: Lack of power in a 184
Posted: Fri Mar 09, 2012 8:32 am
by outdoors4evr
Your tach is probably fine. Just make sure the settings on the tach match the application. One long piece of tape all the way across the diameter of the pulley gives you two counts per 360 degree rotation. Verify that your tach is not looking for one count per 360 degree rotation. It may be reading double the number or some other multiplier.
Getting those advance weights in the distributor to move freely and verifying the springs are functional are key to getting the timing right. The manual says to set your timing to 16 degrees at wide open throttle (high idle) and then to reduce the throttle to an idle and verify the timing moves toward 0 degrees. It is more important to have it right on at wide open throttle than at an idle.
Re: Lack of power in a 184
Posted: Fri Mar 09, 2012 8:44 am
by Dieselrider
outdoors4evr wrote:Your tach is probably fine. Just make sure the settings on the tach match the application. One long piece of tape all the way across the diameter of the pulley gives you two counts per 360 degree rotation. Verify that your tach is not looking for one count per 360 degree rotation. It may be reading double the number or some other multiplier.
Getting those advance weights in the distributor to move freely and verifying the springs are functional are key to getting the timing right. The manual says to set your timing to 16 degrees at wide open throttle (high idle) and then to reduce the throttle to an idle and verify the timing moves toward 0 degrees. It is more important to have it right on at wide open throttle than at an idle.
I just had one piece of tape on the timing pulley and was getting the 1350 reading. The instructions on the tach say if you use more then one piece of tape at different spots around the diameter, you then divide the reading by the number of pieces of tape. But, it also said that was mostly necessary for very low rpm applications. I assumed that one piece of tape would be giving me a direct reading. Do you think this is correct or no?
If the reading is doubled on low idle then I am much closer to where I need to be but way low then on high idle. Thanks
Re: Lack of power in a 184
Posted: Fri Mar 09, 2012 9:27 am
by Jim Becker
Dieselrider wrote:Jim Becker wrote: Your current low idle is so low HIGH. . .
"low idle is low"?
I had a long day.
The code D distributor that belongs on a Cub begins to advance somewhere between 0 and 400 rpm. The advance at speed should be:
400 - 0
800 - 5
1200 - 12
1600 - 16
Re: Lack of power in a 184
Posted: Fri Mar 09, 2012 10:32 am
by outdoors4evr
Reading the manual on your tach is a good thing. I would think one piece of tape from the center of the pulley to the outside edge of the pulley would give you one count per 360 degrees of rotation. Tach's used for model airplanes often require two or three counts per 360 degrees depending on the propeller design they are measuring.
Your 184 engine should be able to idle around 450-500rpm.
When measuring from the PTO that value will read around 390-400rpm.
/Group%20-%2012%20-%20Power%20-%20C-60%20Engine/Page-28.jpg){kind=link}