EngineResearch
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- Sep 6, 2018
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To those that know,
If you open up an L-head vertical shaft 3.5 to 4 hp B&S crankcase and remove the crankshaft, connecting rod, oil thrower, and cam then look down the cylinder to the head end you will see what appears to be that the cylinder has part of the cylinder top area being "covered." This you all know. I am only going through this to explain what I am after. The compression area above the piston that is significantly exposed is what I will be asking about. From where the head on the combustion side has a sloped recess that leads to the valve area we all would call the compression and combustion area plus the tiny gap between the piston and the non recessed area. From where the head begins to have a slope to make the recessed area to the cylinder edge is what length? Cylinder edge to the beginning of the recessed slope found on the head. The reason I want to know this length has to do with some research modifications to a B&S engine. I need at least 0.5" to put an instrument in the head without appreciably affecting compression. It is for research but the measurement should be somewhat consistent between models of L-head 3.5 or 4hp engines.
My intent is to have a fabricated head that will allow for more head thickness and thereby allow for the instrument port to be drilled without weakening the head. Where as the OEM head would not have enough metal thickness to handle stresses, etc, with the port drilled. Does anyone know of a person that fabricates B&S L-head heads?
Be prepared I might have a few other questions with spacial placement of a port in the crowded area.
I will wait for your expert answers.
Thank you in advance,
EngineResearch
If you open up an L-head vertical shaft 3.5 to 4 hp B&S crankcase and remove the crankshaft, connecting rod, oil thrower, and cam then look down the cylinder to the head end you will see what appears to be that the cylinder has part of the cylinder top area being "covered." This you all know. I am only going through this to explain what I am after. The compression area above the piston that is significantly exposed is what I will be asking about. From where the head on the combustion side has a sloped recess that leads to the valve area we all would call the compression and combustion area plus the tiny gap between the piston and the non recessed area. From where the head begins to have a slope to make the recessed area to the cylinder edge is what length? Cylinder edge to the beginning of the recessed slope found on the head. The reason I want to know this length has to do with some research modifications to a B&S engine. I need at least 0.5" to put an instrument in the head without appreciably affecting compression. It is for research but the measurement should be somewhat consistent between models of L-head 3.5 or 4hp engines.
My intent is to have a fabricated head that will allow for more head thickness and thereby allow for the instrument port to be drilled without weakening the head. Where as the OEM head would not have enough metal thickness to handle stresses, etc, with the port drilled. Does anyone know of a person that fabricates B&S L-head heads?
Be prepared I might have a few other questions with spacial placement of a port in the crowded area.
I will wait for your expert answers.
Thank you in advance,
EngineResearch