1938 allis B tractor Serial # B11284 compression test

[yorke]

Motor not stuck, got motor to turn over. @ what time do I need or do not need compression test & what number should I have.
Thanks for Your time !

 

[rustred]

get it running then check the compression. checking it on a sitting engine is not real accurate but still tells you if you have enough to start it, or will show if valves are stuck with next to 0 zero compression. should have at least 100 psi. warm engine at cranking speed with 5 puff's per cylinder. readings should be within 10 percent difference. did you find the engine serial number ?

 

[yorke]

get it running then check the compression. checking it on a sitting engine is not real accurate but still tells you if you have enough to start it, or will show if valves are stuck with next to 0 zero compression. should have at least 100 psi. warm engine at cranking speed with 5 puff's per cylinder. readings should be within 10 percent difference. did you find the engine serial number ?

Thanks for the info !
I am still in la-la land for the hunt of engine #. I would like an exact pic. of where it might be! Like a copy that shows #s
Thanks

 

[Jim.ME]

Thanks for the info !
I am still in la-la land for the hunt of engine #. I would like an exact pic. of where it might be! Like a copy that shows #s
Thanks

Did you read through the old thread I linked for you the other day? It has some pictures.

 

[yorke]

Did you read through the old thread I linked for you the other day? It has some pictures.

Yes Sir I did, I am not the smartest tool in the crib on all this stuff.
I have some good people by the farm that are into tractor stuff.
They not big on the numbers
Maybe if I show pic. They might look too.
Thank U

 

[Watthour]

get it running then check the compression. checking it on a sitting engine is not real accurate but still tells you if you have enough to start it, or will show if valves are stuck with next to 0 zero compression. should have at least 100 psi. warm engine at cranking speed with 5 puff's per cylinder. readings should be within 10 percent difference. did you find the engine serial number ?

100 PSI seems exceptionally high for an engine that is hand-cranked like my '38 was. Further, the advertised compression ratio for the BE engine was 4.92:1 when new. Presuming that there is absolutely NO ring or valve leakage, no valve timing irregularities, and a perfect 14.696 PSIA at sea level, the theoretical maximum would be 72.3 PSI.

 

[yorke]

Yes Sir I did, I am not the smartest tool in the crib on all this stuff.
I have some good people by the farm that are into tractor stuff.
They not big on the numbers
Maybe if I show pic. They might look too.
Thank U

irregularities

My 1938 B serial # 11284 has a starter & Magneto
Thanks for your info & time

 

[Watthour]

Mine was S/N 2527, with a crank and a Fairbanks FMJ mag. Whether bent stick or battery, the compression ratio was the same.

 

[yorke]

Nice looking allis B.
Thanks for all the info

 

[yorke]

Mine was S/N 2527, with a crank and a Fairbanks FMJ mag. Whether bent stick or battery, the compression ratio was the same.View attachment 142395

Mine was S/N 2527, with a crank and a Fairbanks FMJ mag. Whether bent stick or battery, the compression ratio was the same.View attachment 142395

 

[yorke]

U ever find motor # on your B & where was it

 

[Lumbersawyer]

My C has the engine number between the air cleaner and the sediment bowl on the slanted part of the engine flange. CE6544 G

 

[560Dennis]

Always good to have a compression reference to look back at . If issue arises,then you can compare it what it was on this date it was.

 

[yorke]

Good Tractor thinking there.
Found the # 20 on top of sterring gear box.
Got a allis B Book today!
Got carb & semiat old small bowl off & cleaning.
Good day in Wisconsin cold barn

 

[yorke]

Forgot to post this

 

[rustred]

Curious on your compression check. To me at 70 psi that’s a worn out engine.

 

[yorke]

Did not check yet, still cleaning carb, sediment bowl, gas line & gas tank.
Next week hope & pray we get started & running. Then check compression. Hope were above #70.
That allis will not see a hard days of work
Thanks for Input & time still cold working in barn 30 degrees this am