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correct float height m38a1 carb
Posted: Sun Oct 07, 2018 2:57 pm
by ktm25089
Hello,
just to cross check
correct float height for a m38a1 carburetor is 9/64" or 3,6mm???without gasket
and the m38 have 1/4" or 6,3mm
is this real so much difference?
thank you
George
Posted: Sun Oct 07, 2018 4:51 pm
by wesk
I hope you are referencing the applicable manuals.
https://www.dropbox.com/s/8bnc0wlx1zov1 ... 0carbs.pdf
Par 102 fig 61 in TM 9-1826A make it very obvious that there is no gasket on the surface where you make the float measurement.
Note, I did not post the entire TM 9-1826A. Just the parts applicable to the YS series carbs. Unfortunately the Army never bothered to update that TM after 1952 thus the YS950S is not specifically addressed within that manual but in general the rebuilding steps are the same or similar and the YS950S Carter spec sheet I attached to the Manual segment is accurate and yes the two float settings are what they are. There no misprint on the M38 that same 1/4" figure is in the Carter YS637S spec sheet.
If you consider main jet size, metering rod sizes, required fuel flow amount and engine breathing rate they will often vary. Since the F134 and L134 are the same displacement then the extra 12 HP of the F134 comes from increased fuel burn taking advantage of increased volume of air flow the F134 had with the big intakes moved to the head.
Posted: Mon Oct 08, 2018 1:17 am
by ktm25089
Hello Wes
yes i have read the manuals a lot,and they helped me very much
in general your site is a jewel in information
i was asking because there is a lot of difference in float height for the same carburetors without any change in internals.Its about the double on the M38.
So to recheck it in the YS950S is only 9/16" or 3,6mm??
Thanks
George
Posted: Mon Oct 08, 2018 9:24 am
by wesk
Look like you are having some serious short term memory issues!!
I have already explained the need for the different settings in my earlier post!
If you consider main jet size, metering rod sizes, required fuel flow amount and engine breathing rate they will often vary. Since the F134 and L134 are the same displacement then the extra 12 HP of the F134 comes from increased fuel burn taking advantage of increased volume of air flow the F134 had with the big intakes moved to the head.
I hope your new statement below is a typo!
So to recheck it in the YS950S is only 9/16" or 3,6mm??
I have to say NO to this statement.
Read the two manual references again. They are EXACTLY as published in the manual:
This statement is indicative of someone who has not read the spec sheets on the two carbs carefully.
i was asking because there is a lot of difference in float height for the same carburetors without any change in internals.
If you truly believe this then you could not have read the two spec sheets carefully on these two carbs.
There are many changes in the internals!
YS950S Carter Specifications Sheet[/u][/b]
Carter YS637S Specificationsc Sheet

Compare these carefully. The two carbs differ a great deal!
Posted: Mon Oct 08, 2018 11:01 am
by wesk
This should make a direct comparison of the YS carb specs easier:
There have been many ongoing discussions the last 15 years on this subject and the only person to insist they are both 1/4" has never replied to a multitude of requests for a written document to support his claim. He is the Infamous Ben dover over on the G503 board where his emlightenment program consists of you ask he tells and the only proof you get is "He Tells"
Posted: Mon Oct 08, 2018 1:51 pm
by ktm25089
Hi again Wes,
im only asking about the correct float height,
yes i have read your papers and they have a lot of differences,
i see that the the 9/64" or 3,6mm is the correct height?is this OK??
Posted: Mon Oct 08, 2018 10:51 pm
by wesk
I've set them both ways and both ways seemed to work fine.
So, are we finally in agreement that:
i was asking because there is a lot of difference in float height for the same carburetors without any change in internals.
There is significant differences in internals!