FUEL PRESSURE

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JAM
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FUEL PRESSURE

Post by JAM »

I tried the carburetor YS950 on my 134L and I could not adjust its operation because finally had always drowning.
Recently a friend lent me a new SOLEX carburetor and idle RPM up and down in cycles, similar to a large diesel engine.
In your manual recommends placing a pressure regulator calibrated to 1.75-2 PSI between the fuel pump and carburetor.
As I said I have no regulator, hoses tried to do in "Y" a return to the fuel tank, with a small homemade valve, and too a pressure gauge interspersed near the carburetor.
The initial pressure with the valve closed reaches approximately a 10PSI.
I was opening the return until the pressure gradually fell to the SOLEX manual recommended.
Indeed stabilized idle.

Before pressure testing empirically with 950YS would like to know what is the pressure that the pump must produce fuel for YS carburetors, engine both L 134 and F 134, and if relevant to its operation.
I estimate that if there is too much pressure, this will overcome the float on the needle.


Thanks for your opinions

PD Excuse my translation :roll:

José Angel
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wesk
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Post by wesk »

The YS950S is a F134 engine carb. Bore and mount flange are too large for the L134 engine.

The fuel pressure spec for the YS950S on the M38A1 or M170 jeep is 4 1/2 to 5 PSI @ 1800 RPM.

The carb meant for use on the L134 military engine is the YS650S. The fuel pressure spec for that carb in the M38 jeep is 4 to 5 1/4 PSI @ 1800 RPM.
Wes K
45 MB, 51 M38, 54 M37, 66 M101A1, 60 CJ5, 76 DJ5D, 47Bantam T3-C & 5? M100

Mjeeps photo album: http://www.willysmjeeps.com/v2/modules. ... _album.php
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JAM
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Post by JAM »

I know the YS950S corresponds to the F134, but it is the only model that I have to be waterproof. (I have two new, only used in testing)

Unless someone wants to change one of them for a YS637S, and if used, with a repair kit. :roll: :)

The mechanical adaptation already resolved (flange) I posted about it long ago.
http://www.willysmjeeps.com/v2/modules. ... &highlight =

My engine is CJ3A ... there are very significant differences compared to 134L for military use?

Wes, Thank you for the tip of the fuel pressure
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