Spark plugs
Printed From: Unofficial Allis
Category: Allis Chalmers
Forum Name: Farm Equipment
Forum Description: everything about Allis-Chalmers farm equipment
URL: https://www.allischalmers.com/forum/forum_posts.asp?TID=212082
Printed Date: 17 Sep 2026 at 7:49pm
Software Version: Web Wiz Forums 11.10 - http://www.webwizforums.com
Topic: Spark plugs
Posted By: john2189
Subject: Spark plugs
Date Posted: 25 Aug 2026 at 2:51pm
|
I have a bunch of new shorter cj8 champion plugs my uncle gave me that he ran in his weed eater. Can I use them for my allis b? ------------- '41 Allis B '49 Farmall Cub |
Replies:
Posted By: steve(ill)
Date Posted: 25 Aug 2026 at 3:22pm
|
not really a good plan.. the REACH is to short into the cylinder.. you will be burning on the last couple thread in the head.. many people are using NGK plugs instead of the older Champion in the B- C engines. ------------- Like them all, but love the "B"s. |
Posted By: john2189
Date Posted: 25 Aug 2026 at 3:39pm
|
Ok thanks just thought why buy new if those would work. I will never use them for anything else. ------------- '41 Allis B '49 Farmall Cub |
Posted By: john2189
Date Posted: 27 Aug 2026 at 1:51pm
|
None of the local parts stores have autolite 395. Only thing I could get was Champions J8. Wow what a difference. It’s running better than it has for a long time. It did have one fouled plug, wet, shinny black. The other 3 was dry black. So must be running rich. The high speed adjustment doesn’t do much , so something must be plugged. I will order a carb kit. ------------- '41 Allis B '49 Farmall Cub |
Posted By: Coke-in-MN
Date Posted: 28 Aug 2026 at 2:53pm
|
https://www.sparkplug-crossreference.com/convert/AUTOLITE/395%20" rel="nofollow - https://www.sparkplug-crossreference.com/convert/AUTOLITE/395
WOH - the J8 is a short reach plug - 3/8" and the 395 is a long reach - so it works but if and hen you go to replace plugs later the threads in hole will be fouled from using wrong plugs - J8 might work but will cause trouble later - Try Champion N5 ------------- Life lesson: If you’re being chased by a lion, you’re on a horse, to the left of you is a giraffe and on the right is a unicorn, what do you do? You stop drinking and get off the carousel. |
Posted By: john2189
Date Posted: 28 Aug 2026 at 4:17pm
|
Well the head is probably already screwed up. It had 3 Autolite 295 and one Champion J8 from the previous owner. I must have misread Steves earlier post, I read it as the cj8 was a shorter plug, not the reach. So I guess running the J8 won’t do much more damage. If i ever take the head off, I suppose I could get a 14 MM thread tap and clean up the threads. Probably would not be a good idea to do it without taking it off. ------------- '41 Allis B '49 Farmall Cub |
Posted By: john2189
Date Posted: 01 Sep 2026 at 12:12pm
Will the threads be burned up/melted or just carbon fouled? ------------- '41 Allis B '49 Farmall Cub |
Coke-in-MN wrote:Posted By: 8070nc
Date Posted: 01 Sep 2026 at 1:10pm
|
If a short plug is put in a long head carbon will build in the exposed thread. In order to put the proper long plug in you will have to run a tap in it to clean out the threads. I went thru that in a D17 ------------- 1984 80780 1957 D14 DES 300 with 25000 engine 616 tractor |
Posted By: 8070nc
Date Posted: 01 Sep 2026 at 1:16pm
|
The danger is if a person isnt paying attention and they try to screw a long plug in where a shirt plug has been its possibke to ruin the threads ------------- 1984 80780 1957 D14 DES 300 with 25000 engine 616 tractor |
Posted By: SteveM C/IL
Date Posted: 01 Sep 2026 at 5:08pm
| Be best to run a 14mm tap through threads and install correct plugs. Spin motor over with plugs out to take care of carbon dust. Lightly oil threads on plugs. Done. |
Posted By: john2189
Date Posted: 01 Sep 2026 at 5:31pm
|
Thanks ------------- '41 Allis B '49 Farmall Cub |