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Autolite 4100 fuel filter

  • Thread starter Thread starter JC Mustang
  • Start date Start date May 19, 2010

JC Mustang

Founding Member
Nov 1, 2000
142
0
0
Layton, UT
May 19, 2010
#1
  • May 19, 2010
  • #1
I've got a new filter for my Autolite 4100. It does not have tapered threads, which leads me to believe that a seal is formed through mechanical force, and that no thread sealant would be needed. Is this correct? Should I tighten this any more than hand tight?

Thanks.
 
2

2+2GT

10 Year Member
Apr 25, 2009
3,333
10
79
Southeastern Pennsylvania
May 19, 2010
#2
  • May 19, 2010
  • #2
The 4100 (and 2100) used two different filters, depending upon when they were made. The later ones had tapered pipe thread, but the earlier units had an inverted flare connection. The inverted flare should not be installed with thread sealer, since the threads do not seal the connection.
 

JC Mustang

Founding Member
Nov 1, 2000
142
0
0
Layton, UT
May 19, 2010
#3
  • May 19, 2010
  • #3
The carb inlet certainly looks like inverted flare (like this: http://www.wholesalecompressorparts.com/images/CTG.gif). The filter (1/2" UNF threads) screws in nicely while 1/4" NPT does not. I'm guessing it's inverted flare.
 

65FBE2

Member
Mar 8, 2007
283
0
17
Minnasnowta
May 21, 2010
#4
  • May 21, 2010
  • #4
Look into the end of the carb and see if it has a backward looking funnel. What year is the carb? all 65 and older carbs had the inverted flair
 

JC Mustang

Founding Member
Nov 1, 2000
142
0
0
Layton, UT
May 21, 2010
#5
  • May 21, 2010
  • #5
Hmm, I thought I already posted this, but I guess I messed it up.

Yes, inside the fuel inlet looks like a backwards funnel. The foot is stamped 6ZE.
 
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