Create your own blog: viewtopic.php?f=7&t=17487

Float valve seat difference?

All flathead topics
Post Reply
old man emu
Posts: 651
Joined: Sun Mar 25, 2012 7:00 am
Bikes: WLA Mk lll, civilianised
Location: Narellan Vale, New South Wales, Australia

Float valve seat difference?

#1

Post by old man emu » Mon Jul 09, 2018 1:00 am

While working on an M88 carburetor I noticed that there was a difference between the float valve seat that was in the original 1946 carburetor and the new one. The old one is pictured on the left. See that the hole in the old one is lower than on the new one.
Ed's float valve.jpeg
Ed's float valve.jpeg (37.12 KiB) Viewed 81 times
Would the position of the hole affect the operation of the valve, and the filling of the fuel bowl?

Has the float valve seat (Part # 1273-33A) been the same for all Linkert carburetors over time, or has it been redesigned?

Old Man Emu



Buddhahoodvatoloco
Site sponsor
Site sponsor
Posts: 731
Joined: Wed Sep 07, 2016 7:13 pm
Bikes: 1969 FLF
1937 EL Sold
1949 rat bike Sold
1946 FL Sold
Location: san diego

Re: Float valve seat difference?

#2

Post by Buddhahoodvatoloco » Mon Jul 09, 2018 2:25 am

Selcome to the world of repop.

old man emu
Posts: 651
Joined: Sun Mar 25, 2012 7:00 am
Bikes: WLA Mk lll, civilianised
Location: Narellan Vale, New South Wales, Australia

Re: Float valve seat difference?

#3

Post by old man emu » Mon Jul 09, 2018 3:20 am

Even this one has a different design, but the hole in this one is low on the stem, too.
BIg Twin float valve.jpg
BIg Twin float valve.jpg (12.13 KiB) Viewed 72 times
But, does the design change affect fuel flow?

Andygears
Posts: 396
Joined: Tue Feb 05, 2013 12:25 am
Bikes: 1950 panhead, 1999 FLHTCI, 1987 FLHTC custom
Location: Daytona Beach

Re: Float valve seat difference?

#4

Post by Andygears » Mon Jul 09, 2018 11:42 am

My guess would be that the height of the fill hole would not change the action of filling the float bowl. Looking at it from a machinist view, the raised hole would be easier to deburr the inner "breakthrough" burr without damaging the needle seat. I would keep the needle & seat together as a unit and use both old or both new. One other thing I was advised was that the triangle style needle was less prone to hanging than the full diameter. If a small invasive speck entered past the seat then it would be easy to jam the full circle needle body against the wall, but the tri-oval needle style allows more flow and should self clear putting the garbage into the bottom of the bowl.

My two cents
Andygears

Post Reply

Return to “Flathead and Servicar”