This site is not affiliated with AGCO Inc., Duluth GA., Allis-Chalmers Co., Milwaukee, WI., or any surviving or related corporate entity. All trademarks remain the property of their respective owners. All information presented herein should be considered the result of an un-moderated public forum with no responsibility for its accuracy or usability assumed by the users and sponsors of this site or any corporate entity.
The Forum Parts and Services Unofficial Allis Store Tractor Shows Serial Numbers History
Forum Home Forum Home > Allis Chalmers > Farm Equipment
  New Posts New Posts
  FAQ FAQ  Forum Search   Events   Register Register  Login Login


1954 Allis Chalmers won't stay running
 Post Reply Post Reply
Author
Message
  Topic Search Topic Search  Topic Options Topic Options
cabinfourus View Drop Down
Bronze Level
Bronze Level
Avatar

Joined: 03 Jun 2025
Location: Asheville, NC
Points: 27 		Post Options Post Options   Thanks (0) Thanks(0)   Quote cabinfourus Quote  Post ReplyReply Direct Link To This Post Topic: 1954 Allis Chalmers won't stay running
    Posted: 07 Sep 2025 at 8:30am
Hello again, 
I am (still) working on a 54 Allis Chalmers G tractor for my 83-year-old neighbor. So far, it has been a nightmare, but it is coming around. 

BACKGROUND:
The owner had the engine overhauled two years ago. When he got the G home, it ran for about 30 minutes and died. It would start back up, but die after a few minutes. His son, who knows nothing about four-stroke engines, worked on it and made things worse. After his son gave up, the tractor would not run at all.

MY REPAIRS:
I found that his son had wired the engine backwards. He had even wired the coil backwards. After I got the tractor running again, it would run for 8–10 minutes on a cold start, before stalling out. After the engine is warm, it will only run for 1–2 minutes. 

PARTS REPLACED:
Fuel tank, fuel line, starter motor, battery, carburetor, sediment bowl, coil (internal resister), condenser, points, wiring harness, plug wires, plugs, and cut off switch. 

PARTS REPLACED TWICE:
Rebuilt carburetor, coil (internal resister), points, condenser, carburetor main jet, and plugs. 

DIAGNOSTICS:
I put a spark tester inline and watched the spark on first start up. When the engine died, the spark was okay. I removed the fuel line from the carburetor and the fuel supply was good. I checked the timing of the engine, and it was dead on. I checked the points gap, and it was good at .020

THINGS TO KNOW:
This tractor has seen many mechanics. Someone replaced the cut-off switch with a household light switch. I rebuild the wiring harness with all new wire, due to a ground problem at the starter. It has been converted to 12v, and is why I used a coil with the internal resister. The problem seems to be heat related. The 12v alternator is not charging. I did replace the condenser with a capacitor, just to see, but it didn't help. 

Guys, I am stumped! I am a retired dealership technician with 35 years of line work under my belt. Never have I given up on a repair, but this thing has been a nightmare. I am open to any and all suggestions, and will report back when I find a repair that works. 

Thanks for allowing me to request help on your forums, and I hope you all have a great week. 
Back to Top
Sponsored Links


Back to Top
steve(ill) View Drop Down
Orange Level Access
Orange Level Access
Avatar

Joined: 11 Sep 2009
Location: illinois
Points: 88080 		Post Options Post Options   Thanks (0) Thanks(0)   Quote steve(ill) Quote  Post ReplyReply Direct Link To This Post Posted: 07 Sep 2025 at 8:44am
sounds like your a good mechanic and you know what the problelms are.. You need gas and spark to run and you know that... That narrows it down to fuel flow and spark... You have done the carburetor multiple times and the coil  / condenser multiple times.. If it has good spark when it gets hot and shuts off, the only things i can think of are fuel line getting hot and vaporize, or spark plugs breaking down when hot, ( but you think both of those have been verified ??) etc.. another possibility is never reject the possibility that the CONDENSER is bad... even 1-2 new ones are not a guarantee that they are GOOD ( when they get hot)..  NEW 12v coils normally are good to go.. I never got a NEW COIL that didnt work when hot.

and as gas leaves the fuel tank and goes to the carb, you need makeup air to enter the tank. Make sure the tank is vented with the cap. and NOTHING is floating around in the tank that can block the outlet.


Edited by steve(ill) - 07 Sep 2025 at 8:48am
Like them all, but love the "B"s.
Back to Top
Les Kerf View Drop Down
Orange Level
Orange Level


Joined: 08 May 2020
Location: Idaho
Points: 1328 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Les Kerf Quote  Post ReplyReply Direct Link To This Post Posted: 07 Sep 2025 at 9:48am
Originally posted by steve(ill) steve(ill) wrote:

...
and as gas leaves the fuel tank and goes to the carb, you need makeup air to enter the tank. Make sure the tank is vented with the cap. and NOTHING is floating around in the tank that can block the outlet.

Yup.
I have had both of those problems more than once Confused
Back to Top
mdm1 View Drop Down
Orange Level
Orange Level
Avatar

Joined: 12 Sep 2009
Location: Onalaska, WI
Points: 2680 		Post Options Post Options   Thanks (0) Thanks(0)   Quote mdm1 Quote  Post ReplyReply Direct Link To This Post Posted: 07 Sep 2025 at 12:48pm
Try running it with air filter tube disconnected from the carb.
Everything is impossible until someone does it! WD45-trip loader 1947 c w/woods belly mower, 1939 B, #3 sickle mower 1944 B, 2 1948 G's. Misc other equipment that my wife calls JUNK!
Back to Top
Gary View Drop Down
Orange Level Access
Orange Level Access


Joined: 13 Sep 2009
Location: Peterborough,On
Points: 5902 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Gary Quote  Post ReplyReply Direct Link To This Post Posted: 07 Sep 2025 at 4:41pm

Luckily MD has hit on the third thing that is required for an engine to run, and that is Air to have Oxygen.

Air is one of the 3 standard requirements to sustain a FIRE.

Verify that Air is getting through the Air Cleaner and in to the Carb to mix with the Fuel.

G
Back to Top
cabinfourus View Drop Down
Bronze Level
Bronze Level
Avatar

Joined: 03 Jun 2025
Location: Asheville, NC
Points: 27 		Post Options Post Options   Thanks (0) Thanks(0)   Quote cabinfourus Quote  Post ReplyReply Direct Link To This Post Posted: 19 Sep 2025 at 2:19pm
Okay guys, 

This is what I have done, so far. 
Checked and cleaned the tank.
Replaced the fuel lines.
Installed an inline spark tester to see how the spark was, when it shut off. (good spark)
Removed the air filter line, no change. 
Tried spraying carb cleaner into the carb when it starts to die, no change. 
Replaced condenser, no change.
I did notice the voltage regulator is reading low volts, with a full charge. Maybe a bad switch? Someone installed a household light switch as the on/off switch. 

I am baffled!! Never in my life. 

Thanks for all the suggestions. 
If I ever figure it out, I will post it. 


Edited by cabinfourus - 19 Sep 2025 at 2:23pm
Back to Top
DPKII View Drop Down
Bronze Level
Bronze Level
Avatar

Joined: 08 Mar 2023
Location: Texas
Points: 70 		Post Options Post Options   Thanks (0) Thanks(0)   Quote DPKII Quote  Post ReplyReply Direct Link To This Post Posted: 19 Sep 2025 at 3:56pm
Any chance it could be loosing compression once warmed up?  

David
Back to Top
steve(ill) View Drop Down
Orange Level Access
Orange Level Access
Avatar

Joined: 11 Sep 2009
Location: illinois
Points: 88080 		Post Options Post Options   Thanks (0) Thanks(0)   Quote steve(ill) Quote  Post ReplyReply Direct Link To This Post Posted: 19 Sep 2025 at 4:48pm
thats an odd ball....... were misssing SOMETHING... as you say you Verify it has spark when it starts to die... makes you think it is Fuel Related ... but you also say it will not run on ether .... so something does not line up... If it will not HIT on ether, then im still betting on the spark.... maybe you got a couple cylinders sparking, and not the other two ?

David has a good idea... Things that change when you get HOT are valve clearance and electronics.... air flow and fuel flow normally are constant..


Edited by steve(ill) - 19 Sep 2025 at 4:54pm
Like them all, but love the "B"s.
Back to Top
Tracy Martin TN View Drop Down
Orange Level Access
Orange Level Access
Avatar

Joined: 11 Sep 2009
Location: Gallatin,TN
Points: 10811 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Tracy Martin TN Quote  Post ReplyReply Direct Link To This Post Posted: 19 Sep 2025 at 7:59pm
I would check the hot wire running into distributor. The post might be grounding out when warm. Might be cracked. How loose are the bushings in distributor? HTH, Tracy
No greater gift than healthy grandkids!
Back to Top
Les Kerf View Drop Down
Orange Level
Orange Level


Joined: 08 May 2020
Location: Idaho
Points: 1328 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Les Kerf Quote  Post ReplyReply Direct Link To This Post Posted: 19 Sep 2025 at 8:51pm
Originally posted by cabinfourus cabinfourus wrote:

...
Installed an inline spark tester to see how the spark was, when it shut off. (good spark)
... 

Please describe exactly where you had the spark tester installed.
Back to Top
Wispitfiremike View Drop Down
Silver Level
Silver Level


Joined: 28 Mar 2017
Location: Milwaukee, WI
Points: 204 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Wispitfiremike Quote  Post ReplyReply Direct Link To This Post Posted: 21 Sep 2025 at 6:32am
Since it was overhauled not long ago and I don't know much about that engine is there any chance thrust bearing is out of spec.? Sure sounds like normal fail stuff has been gone over. 
Back to Top
mdm1 View Drop Down
Orange Level
Orange Level
Avatar

Joined: 12 Sep 2009
Location: Onalaska, WI
Points: 2680 		Post Options Post Options   Thanks (0) Thanks(0)   Quote mdm1 Quote  Post ReplyReply Direct Link To This Post Posted: 21 Sep 2025 at 6:44am
I just went through something like this with one of my G's.Mine had no power. Would start right up and run.Ended up being the timing.
Everything is impossible until someone does it! WD45-trip loader 1947 c w/woods belly mower, 1939 B, #3 sickle mower 1944 B, 2 1948 G's. Misc other equipment that my wife calls JUNK!
Back to Top
 Post Reply Post Reply
  Share Topic   

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 11.10
Copyright ©2001-2017 Web Wiz Ltd.

This page was generated in 0.070 seconds.


Help Support the
Unofficial Allis Forum