47 farmall a hard start

Farmall Super A, AV, 100, 130, & 140 1939 - 1973

Moderator: Team Cub

Forum rules
Notice: For sale and wanted posts are not allowed in this forum. Please use our free classifieds or one of our site sponsors for your tractor and parts needs.
Jack jr
Posts: 5
Joined: Sun Jun 27, 2021 4:56 am
Zip Code: 7155

47 farmall a hard start

Postby Jack jr » Sun Jun 27, 2021 5:11 am

G'day I have a 1947 Farmall a that is temperamental,
It will sometimes sit for 2 weeks I will give it 2 cranks with choke 3rd without choke and it will go, then you will shut it off for any amount of time try start it and it wont start on the crank no matter what you do, but if you roll start it it will go within 6 feet and run fine, temp seems to make no difference I changed the condenser, points, cap, rotor, plugs and it made no difference sometimes it go's sometimes not without a roll start,
I have to crank it very slowly to get the impulse coupling to work but it will start like that sometimes.
i am at a loss with it.

Cheers Jack jr

Jim Becker
Team Cub
Team Cub
Posts: 15860
Joined: Sun Feb 02, 2003 2:59 pm
Zip Code: 55319
Circle of Safety: Y
Location: MN

Re: 47 farmall a hard start

Postby Jim Becker » Sun Jun 27, 2021 12:06 pm

STOP.

Do not try crank starting until you get the impulse coupling fixed. The risk of a kick-back and consequent broken arm is too big.

Your starting problem has all the symptoms of a non-functioning impulse coupling. So dealing with the impulse coupling will probably cure your starting problem.

Again, do not try crank starting until you get the impulse coupling fixed.

Jack jr
Posts: 5
Joined: Sun Jun 27, 2021 4:56 am
Zip Code: 7155

Re: 47 farmall a hard start

Postby Jack jr » Sun Jun 27, 2021 4:14 pm

G'day Jim thanks for the reply I will check but I believe the impulse coupling is working as you can crank it as slow as you want and you can hear it click and get a good spark should the impulse work on all 4 cylinders or just 1 and 3.
Cheers Jack jr

Jim Becker
Team Cub
Team Cub
Posts: 15860
Joined: Sun Feb 02, 2003 2:59 pm
Zip Code: 55319
Circle of Safety: Y
Location: MN

Re: 47 farmall a hard start

Postby Jim Becker » Sun Jun 27, 2021 4:40 pm

It should work the same on all 4 cylinders. The coupling has 2 pawls, one engages the stop pin for cylinders 1 and 4, the other for 3 and 2.

Jack jr
Posts: 5
Joined: Sun Jun 27, 2021 4:56 am
Zip Code: 7155

Re: 47 farmall a hard start

Postby Jack jr » Sun Jun 27, 2021 5:06 pm

Ok so one of mine isn't engaging I have never pulled one apart is there anything to be aware of or a the relatively simple thanks for you help.
Cheers Jack jr

Jim Becker
Team Cub
Team Cub
Posts: 15860
Joined: Sun Feb 02, 2003 2:59 pm
Zip Code: 55319
Circle of Safety: Y
Location: MN

Re: 47 farmall a hard start

Postby Jim Becker » Sun Jun 27, 2021 10:28 pm

You need to look at the Magneto Service Manual in the PDF manuals. (Quick Links at top left of this page). Go to PDF Manuals, Service Manuals, Blue Ribbon Service Manuals, GSS-5035 Service Manual Magnetos. There is a section on the H-4 magneto, which I assume is what you have.

Unfortunately, you about have to have a special tool to remove the coupling from the magneto. To make magneto installation easier, follow these steps for removal:
- Slowly turn the engine by hand until you hear the impulse click.
- Remove the distributor cap and make note of the direction the rotor is pointing.
- Remove the magneto. Do NOT turn the engine while the magneto is removed.
- To install, turn the magneto backwards until the rotor points in the direction previously noted.
- Use the book procedure to time the magneto.

Jack jr
Posts: 5
Joined: Sun Jun 27, 2021 4:56 am
Zip Code: 7155

Re: 47 farmall a hard start

Postby Jack jr » Wed Jun 30, 2021 3:07 am

G'day I pulled the impulse apart and but couldn't find anything broken, the springs seemed very loose and i may have upset them pulling it off they are a bit rusty, I have looked around and don't seem to be able to buy any in Australia does anyone have any idea where I could get 2? Tractor still starts if you roll start it or crank start it pulling the crank quickly.
Cheers Jack jr

Jim Becker
Team Cub
Team Cub
Posts: 15860
Joined: Sun Feb 02, 2003 2:59 pm
Zip Code: 55319
Circle of Safety: Y
Location: MN

Re: 47 farmall a hard start

Postby Jim Becker » Wed Jun 30, 2021 6:49 am

Look at the stop pin and the very corner of the pawls where they engage the stop pin. They may be worn enough so they don't engage reliably. A worn pin can probably be knocked out and reinstalled at a half turn to get a new surface. Wear at the pivot point of the pawls may be a problem too.

Reread my cranking comments in my first post.

Jack jr
Posts: 5
Joined: Sun Jun 27, 2021 4:56 am
Zip Code: 7155

Re: 47 farmall a hard start

Postby Jack jr » Sat Jul 03, 2021 6:15 pm

G'day I pulled the impulse apart aging and got it working better with a slow crank I have a big blue spark, still only starts sometimes on the crank I recently changed with 20 year old plugs in it to some champion d16 the tractor doesn't work very hard just road runs and pulling trailers mostly are these plugs to cold? cheers Jack jr.

Gary Dotson
Team Cub Mentor
Team Cub Mentor
Posts: 4500
Joined: Thu Aug 03, 2006 6:20 am
Zip Code: 43358
Tractors Owned: 48 Cub Diesel (Cubota)
53 Cockshutt 20 restored (Shooter)
52 Cockshutt 20 unrestored
47 Leader "B" (Herckie)
49 Leader "D" (Princess)
49 Leader "D" very rough
48 Leader "D" unrestored
Kubota B6200E
Kubota B6200HST
Kubota B8200HST-D
Circle of Safety: Y
Location: OH West Mansfield

Re: 47 farmall a hard start

Postby Gary Dotson » Sun Jul 04, 2021 6:47 am

They are not necessarily too cold but you might get a little better performance from D-21’s.


  • Similar Topics
    Replies
    Views
    Last post

Return to “Farmall A, Super A, AV, 100, 130 & 140”

Who is online

Users browsing this forum: No registered users and 1 guest