I was having issues with the governor so I opened the engine. Since I had it open, I decided to change out the piston rings. When reattaching the connecting rods as per the repair manual instructions, I found that they are binding on the Crankshaft. I applied oiil and it still takes a wrench to turn the crank. I didn’t change the rods or the crankshaft. Why should they be binding?
B&S 18 HP Opposed Twin Binding
- Thread starter George K
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Are you turning it with the crankcase cover on?
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crankcase cover/sump are one in the same.
If the sump is on, you may not have the proper end play for the crank and it's binding, the opposed twins used different gasket thickness to set crank end play. Does it turn free with the cover off?
What's the engines model #?
Hammermechanicman
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Are the rods binding on the crank or is the crank being pinched by lack of clearance between crankcase and sump cover?
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From my opposed twin manual:
Crankshaft endplay is .002"-.026" (.05mm to .66 mm) on vertical crankshaft engines, On horizontal shaft engines it is .004" to .012" with one .015" gasket in place, if end play is less than .002" which can be the case if a new crankcase cover is used, additional gaskets, 005",.009" or .015" thick may be required to obtain correct end play.
Crankshaft endplay is .002"-.026" (.05mm to .66 mm) on vertical crankshaft engines, On horizontal shaft engines it is .004" to .012" with one .015" gasket in place, if end play is less than .002" which can be the case if a new crankcase cover is used, additional gaskets, 005",.009" or .015" thick may be required to obtain correct end play.
With rods disconnected, the crank turns easily.
Briggs and Stratton Model 422707-1214-01
I also put in some off brand oil seals. That may be causing the improper end play. I just got 2 new B&S seals. Let me take off sump cover and I will let you know if it turns freely.
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You did get standard rings didn't you?
I’m learning slowly. No, I got off brand rings. But just to see if it was the rings, I took them off and put back the old ones. Still binding. So I don’t think the rings are the issue.
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I doubt this is the issue, but what are you torquing the rod bolts too?
in my manual it says,
"Torque connecting rod screws to 190 inch pounds, rotate crank 2 revolutions to check for binding, connecting rods should be free to move SIDEWAYS on the crank pin. (what the rods bolt too)
*Note: failure to use a torque wrench can result in loose connecting rod causing engine damage or tight connecting rods causing scoring.
in my manual it says,
"Torque connecting rod screws to 190 inch pounds, rotate crank 2 revolutions to check for binding, connecting rods should be free to move SIDEWAYS on the crank pin. (what the rods bolt too)
*Note: failure to use a torque wrench can result in loose connecting rod causing engine damage or tight connecting rods causing scoring.