Antique Engines and Old Iron
[Home] - [HELP] - [Forums] - [Groups] - [Classified Ads] - [Subscribe] - [Books] - [Sponsors] -

Go Back   SmokStak > SmokStak® Antique Engine Community > Hit & Miss Gas Engine Discussion
Forgot Password? Join Us!

Notices

Hit & Miss Gas Engine Discussion Meet collectors of hit and miss engines, ask questions about collecting, restoring and showing antique flywheel engines.

Hit & Miss Gas Engine Discussion

Need your help with Fuller and Johnson NC


this thread has 30 replies and has been viewed 2350 times

Reply
 
Thread Tools Display Modes
  #21  
Old 03-09-2017, 01:41:45 PM
Bill Hazzard Bill Hazzard is offline
Registered
 
Join Date: Nov 2004
Location: Pennsylvania USA
Posts: 2,182
Thanks: 3,948
Thanked 4,722 Times in 1,215 Posts
Default Re: Timing nomenclature

What you wrote from David's old engines is confusing to say the least. Stick with top dead center (TDC) which is when the piston is all the way in and bottom dead center (BDC) when the piston is all the way out. The spark should occur about 20 degrees before TDC. It can be less than the factory mark if you slow the engine down. The slower the engine goes then the closer to TDC the spark should be.
Reply With Quote
Sponsored Links
  #22  
Old 03-09-2017, 02:19:21 PM
Coomba Coomba is offline
Registered
 
Join Date: Nov 2016
Location: Rockton, Illinois, USA
Posts: 23
Thanks: 8
Thanked 13 Times in 5 Posts
Default Re: Timing nomenclature

Quote:
Originally Posted by WCraig View Post
Coomba, as you are troubleshooting your problem, it helps to keep your thread in one post. That way, the experts on here can keep up with the whole problem and whole set of issues. Ive learned that the knowledge available on here can fix any problem. Im sure you will get your Fuller running.
Although I have been getting a lot of response, to my original question. I have asked other questions in that thread that have gone unanswered, also I have explained the procedures that I have done in several of my post, only to find that in the answering post, telling me to do what I have already done. Please, I'm not trying to be insulting or arrogant, I know you guys are doing your best to help me. I just did not want this question to get lost in the shuffle.
Reply With Quote
  #23  
Old 03-09-2017, 03:55:00 PM
Andrew Mackey Andrew Mackey is offline
Moderator
 
Join Date: Nov 2004
Location: Rockaway, New Jersey USA
Posts: 14,149
Thanks: 1,992
Thanked 6,767 Times in 4,301 Posts
Default Re: Timing nomenclature

Lets set a few things straight. There are 2 top dead centers in a 4 stroke engine (TDC). TDC occurs when the piston travel is at the top of its travel within the cylinder, toward the head or combustion chamber. One is TDC Compression, the other TDC between exhaust and intake strokes. There are also 2 bottom dead centers (BDC). BDC means the piston cannot go any further toward the open end of the cylinder. One is after the power stroke (after ignition and burning of fuel in the cylinder), and the other after completion of the intake stroke.

Lets go thru the complete 4 cycle operation of your hit & miss engine: Starting at TDC between strokes - with the flywheels turning clockwise, with the head on the left and the magneto (WICO EK) facing you, mag timer should be set to the retarded position (Lever up). As the flywheel is turned, the piston goes down the bore, beginning the Intake stroke. This draws fuel and air into the cylinder, past the intake valve. You should hear the valve rattle a bit as the piston recedes down the bore of the cylinder. When the piston gets to BDC Intake, the intake valve remains closed, sealing the cylinder. As the flywheels continue to turn, the piston now goes back up the bore on the Compression stroke, compressing the trapped gases inside. When the piston reachees TDC Compression, with the timer set at start or retarded, the magneto should trip exactly at TDC Compression, causing a spark within the combustion chamber. The fuel/air charge is now at maximum compression, and if the mixture is right, it should ignite and burn, raising the pressure within the combustion chamber. The combustion chamber is the space at the top of the closed cylinder, that holds the compressed fuel/air mixture. As the flywheels continue to turn, the piston now goes back down the cylinder bore, under tremendous pressure made by the now burning fuel. This is the Power stroke. When the piston nears BDC Power stroke, the fuel/air burn is nearly complete, and the cam begins to open the exhaust valve, around 20 degrees from BDC power stroke. This relieves pressure on the piston, and as the piston reaches BDC power, it again reverses direction and begins the exhaust stroke. As the flywheels continue to turn, the piston goes up the bore, pushing the burnt gasses out past the now open exhaust valve. As the piston nears TDC Exhaust, the cam closes the exhaust valve. It should be just closed at TDC between intake and exhaust, and the cycle repeats. If the exhaust timing is not correct, the engine cannot process all 4 strokes efficiently, and the engine won't run. Once the engine begins to fire, the timer is advanced (lever down), which advances the timing to a preset position, determined by the manufacturer for the best power and economy. In your case, approximately 20 degrees BEFORE TDC Compression. The reason for advance is to allow for extra burn time before TDC Compression, to allow more complete burning of the fuel/air mix and to get maximum thrust from the fuel/air against the piston. The reason for ignition retard is to prevent kick back during the starting process. Kick back is when the spark occurs before TDC Compression and ignites the fuel/air charge, and the flywheels do not have enough momentum to carry the engine over TDC Compression. If you are trying to start an engine by hand, or with a hand crank, and the engine fires early (Before TDC Compression, the sudden reversal of the flywheels and crank can cause serious injury.

Here is what you need to verify: A) good spark. Try another spark plug) B)with the ignition set at retarded, the magneto trips right at TDC. C) the engine is getting sufficient gas during the intake stroke. D) starting at TDC INTAKE, roll the engine thru all 4 cycles and determine ALL timing points visually.

1) Intake, is the engine drawing fuel and air? 2) is there any leakage of the intake charge from the valves or past the piston in the cylinder on the compression stroke? 3) does the mag trip right at TDC Compression? 4) As the engine turns thru the power stroke, does the exhaust valve begin to open at about 20 degrees BEFORE the piston reaches the end of the power stroke (BDC power stroke)? As the piston nears TDC Exhaust stroke, does the exhaust valve close nearly at the exact TDC between intake and exhaust?

Another thing to try is to see if you can get a spark plug with a longer electrode, one that extends further into the combustion chamber. if your plug is too short, the spark may be shielded by being too far away from the fuel/air mix, within the combustion chamber itself.
Reply With Quote
The Following User Says Thank You to Andrew Mackey For This Post:
  #24  
Old 03-09-2017, 04:35:57 PM
Mikey NY Mikey NY is offline
Subscriber
 
Join Date: Dec 2010
Location: Central Valley, New York
Posts: 848
Thanks: 79
Thanked 538 Times in 259 Posts
Default Re: Timing Nomenclature

I also repeated the same things over and over again, and it turns out I was doing the same thing wrong over and over again. I had to revisit my problem many times before I was able to interpret the info correctly and get it to run. I mentioned before there is an article in gas engine magazine called tramming. Here it is.
http://www.gasenginemagazine.com/gas...es/tramming-in
read the article a few times or a few more times. and maybe it will help you out. I did not actually go thru the whole tramming process for mine but the article answered some of my questions. good luck with it.

---------- Post added at 03:35:57 PM ---------- Previous post was at 03:29:02 PM ----------

Absolutely EXCELLANT explanation Andrew Mackey. It just doesn't get any better than that. Maybe your excellent explanation should be posted as a sticky note at the top of the hit and miss section page. Really
Reply With Quote
The Following User Says Thank You to Mikey NY For This Post:
  #25  
Old 03-09-2017, 04:50:12 PM
Craig A's Avatar
Craig A Craig A is offline
Moderator
 
Join Date: Nov 2004
Location: Wisconsin, USA
Posts: 15,479
Thanks: 16,787
Thanked 20,690 Times in 5,985 Posts
Default Re: Need your help with Fuller and Johnson NC

I merged Coomba's F&J threads to make things easier for everyone.......
Reply With Quote
The Following User Says Thank You to Craig A For This Post:
  #26  
Old 03-09-2017, 05:59:03 PM
Doug Kimball's Avatar
Doug Kimball Doug Kimball is offline
Subscriber
 
Join Date: Oct 2004
Location: Kennebunk, Maine, USA
Posts: 3,710
Thanks: 2,045
Thanked 3,105 Times in 1,361 Posts
Default Re: Need your help with Fuller and Johnson NC

Coomba,
Time it to spark about 15 to 20 degrees before inner dead center. It should run at that setting. You may want to fine tune it after you get it running.
__________________
In Kennebunk, Maine;
Doug Kimball
Reply With Quote
  #27  
Old 03-11-2017, 11:27:41 AM
Coomba Coomba is offline
Registered
 
Join Date: Nov 2016
Location: Rockton, Illinois, USA
Posts: 23
Thanks: 8
Thanked 13 Times in 5 Posts
Default Re: Timing nomenclature

Quote:
Originally Posted by Andrew Mackey View Post
Lets set a few things straight. There are 2 top dead centers in a 4 stroke engine (TDC). TDC occurs when the piston travel is at the top of its travel within the cylinder, toward the head or combustion chamber. One is TDC Compression, the other TDC between exhaust and intake strokes. There are also 2 bottom dead centers (BDC). BDC means the piston cannot go any further toward the open end of the cylinder. One is after the power stroke (after ignition and burning of fuel in the cylinder), and the other after completion of the intake stroke.

Lets go thru the complete 4 cycle operation of your hit & miss engine: Starting at TDC between strokes - with the flywheels turning clockwise, with the head on the left and the magneto (WICO EK) facing you, mag timer should be set to the retarded position (Lever up). As the flywheel is turned, the piston goes down the bore, beginning the Intake stroke. This draws fuel and air into the cylinder, past the intake valve. You should hear the valve rattle a bit as the piston recedes down the bore of the cylinder. When the piston gets to BDC Intake, the intake valve remains closed, sealing the cylinder. As the flywheels continue to turn, the piston now goes back up the bore on the Compression stroke, compressing the trapped gases inside. When the piston reachees TDC Compression, with the timer set at start or retarded, the magneto should trip exactly at TDC Compression, causing a spark within the combustion chamber. The fuel/air charge is now at maximum compression, and if the mixture is right, it should ignite and burn, raising the pressure within the combustion chamber. The combustion chamber is the space at the top of the closed cylinder, that holds the compressed fuel/air mixture. As the flywheels continue to turn, the piston now goes back down the cylinder bore, under tremendous pressure made by the now burning fuel. This is the Power stroke. When the piston nears BDC Power stroke, the fuel/air burn is nearly complete, and the cam begins to open the exhaust valve, around 20 degrees from BDC power stroke. This relieves pressure on the piston, and as the piston reaches BDC power, it again reverses direction and begins the exhaust stroke. As the flywheels continue to turn, the piston goes up the bore, pushing the burnt gasses out past the now open exhaust valve. As the piston nears TDC Exhaust, the cam closes the exhaust valve. It should be just closed at TDC between intake and exhaust, and the cycle repeats. If the exhaust timing is not correct, the engine cannot process all 4 strokes efficiently, and the engine won't run. Once the engine begins to fire, the timer is advanced (lever down), which advances the timing to a preset position, determined by the manufacturer for the best power and economy. In your case, approximately 20 degrees BEFORE TDC Compression. The reason for advance is to allow for extra burn time before TDC Compression, to allow more complete burning of the fuel/air mix and to get maximum thrust from the fuel/air against the piston. The reason for ignition retard is to prevent kick back during the starting process. Kick back is when the spark occurs before TDC Compression and ignites the fuel/air charge, and the flywheels do not have enough momentum to carry the engine over TDC Compression. If you are trying to start an engine by hand, or with a hand crank, and the engine fires early (Before TDC Compression, the sudden reversal of the flywheels and crank can cause serious injury.

Here is what you need to verify: A) good spark. Try another spark plug) B)with the ignition set at retarded, the magneto trips right at TDC. C) the engine is getting sufficient gas during the intake stroke. D) starting at TDC INTAKE, roll the engine thru all 4 cycles and determine ALL timing points visually.

1) Intake, is the engine drawing fuel and air? 2) is there any leakage of the intake charge from the valves or past the piston in the cylinder on the compression stroke? 3) does the mag trip right at TDC Compression? 4) As the engine turns thru the power stroke, does the exhaust valve begin to open at about 20 degrees BEFORE the piston reaches the end of the power stroke (BDC power stroke)? As the piston nears TDC Exhaust stroke, does the exhaust valve close nearly at the exact TDC between intake and exhaust?

Another thing to try is to see if you can get a spark plug with a longer electrode, one that extends further into the combustion chamber. if your plug is too short, the spark may be shielded by being too far away from the fuel/air mix, within the combustion chamber itself.
Thank You, I will report back, but some family medical has kept me from my shop.
Reply With Quote
  #28  
Old 03-21-2017, 10:18:44 PM
Coomba Coomba is offline
Registered
 
Join Date: Nov 2016
Location: Rockton, Illinois, USA
Posts: 23
Thanks: 8
Thanked 13 Times in 5 Posts
Default Re: Need your help with Fuller and Johnson NC

I would like to thank everyone for their help. Armed with the information you provided, I was able to adjust the exhaust valve and get the engine running. Hooray!! It seems a little rough, and may need some fine tuning, but right now I just want to enjoy it for a while. I was surprised at how little I needed to open the fuel valve, and how cool the engine ran. Thanks again.


https://www.youtube.com/watch?v=YjRl...ature=youtu.be
Reply With Quote
The Following User Says Thank You to Coomba For This Post:
  #29  
Old 03-22-2017, 06:17:25 AM
flatheadjim flatheadjim is offline
Registered
 
Join Date: Jan 2017
Location: Columbia, Pennsylvania, USA
Posts: 8
Thanks: 0
Thanked 2 Times in 2 Posts
Default Re: Need your help with Fuller and Johnson NC

i had the same problem with mine . i tried everything i could think of . when i pulled the piston out i found that the rings were stuck the engine seemed to have compression but after i freed up the rings compression was much better and started on first try.
Reply With Quote
  #30  
Old 03-22-2017, 09:38:08 AM
Rich Mueller Sr's Avatar
Rich Mueller Sr Rich Mueller Sr is offline
Subscriber
 
Join Date: Jan 2010
Location: Wright City, Missouri
Posts: 5,584
Thanks: 7,416
Thanked 4,925 Times in 2,476 Posts
Default Re: Need your help with Fuller and Johnson NC

Actually that is running pretty good a little rich maybe, which mine does the black smoke thing to and these little guys like to run a little faster, not as much meat on the flywheels and short strokes as the big guys.I think it is Jason Dahmn that has on ebay a latch out arm that is new old stock that will fit these , you have to do some bending to get it right, says that in the book to, but it took a lot of slop out of the cam slam, and held the exhaust open a tad farther the old it had been filed one etc in the past and wouldn't lock up right some times. Mine has the heavy spoke wheels and coasts forever now....
__________________
United Gasoline Engine Registry www.augermo.com
Reply With Quote
  #31  
Old 09-10-2019, 09:17:42 AM
Vinnie317 Vinnie317 is offline
Registered
 
Join Date: May 2019
Location: Syracuse, New York
Posts: 6
Thanks: 0
Thanked 5 Times in 2 Posts
Default Re: Need your help with Fuller and Johnson NC

I tried a number of different spark plugs in my F & J NC 2 1/2 Hp and found that it took right off with a Champion W89D
Reply With Quote
Reply

Bookmarks


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

F o r u m Jump

Similar Threads Chosen at Random
Thread Thread Starter F o r u m Replies Last Post
fuller and johnson nc 1 1/2 Linkmaster57 Hit & Miss Gas Engine Discussion 1 06-29-2014 03:25:08 AM
New Fuller Johnson K Preston Wells Hit & Miss Gas Engine Discussion 9 01-03-2012 08:08:01 PM
Fuller and Johnson NC Jordan Hit & Miss Gas Engine Discussion 6 12-31-2011 06:18:39 PM
Fuller & Johnson no tag? sammyg Unidentified Engines 4 04-17-2011 04:22:27 PM
Value of Fuller Johnson? Loren W Antique Engine Archives 3 04-09-2004 03:26:15 PM


Use "Ctrl" mouse wheel to change screen size.
All times are GMT -4. The time now is 03:07:18 PM.

Smokstak and Enginads site search!


All use is subject to our TERMS OF SERVICE
SMOKSTAK® is a Registered Trade Mark - A Community of Antique Engine Enthusiasts
Copyright © 2000 - 2019 by Harry Matthews P.O. Box 5612 - Sarasota, FL 34277