Rod side thrusts have the same effect. There should be a published specification for the side clearance of the rod. Figure 10 - Checking Connecting Rod Side Clearance CYLINDER BLOCK Check cylinder block for cracks and check inside of cylinder bores for scratches, scoring, pitting, out-of-round and taper. David-----Check my web page for First Gen Camaro suspension info: David's Motorsports page Justin Miller 19,223 views. That’s one reason why rod side clearance is a critical measurement when assembling an … Too much and windage increases as noted. Excessive connecting rod bearing clearance affects oil consumption. A typical pin fitting clearance is within the range of 0.0008- to 0.0010-inch to the connecting rod. A lot of that oil comes from the oil bleeding out at the throws. The piston and cylinder are splash lubricated; by oil passing through the connecting rod bearing and onto the cylinder wall. EXCESSIVE Piston to Bore Clearance? In the latter case, a connecting rod or bearings may be loosely installed, resulting in excess clearance, noise, and damage. My Smokey Yunick book says .013" to .015". Friction and horsepower Says rod side clearance is not critical but if you get up to .025" then you are getting too loose. Connecting rods are guided by either the crankshaft or the piston. For most automobile engines, the connecting rods are designed and sized so that the directional forces are controlled at the big end by the crankshaft. Use of synthetic oils with their better flow properties can help to reduce fluid film friction. Reactions: GreenS550 , Martinnfb , mustang charlie and 2 others Measuring connecting rod side clearance - Duration: 0:40. You would check this with a feeler gauge. Re: Connecting Rods Side Clearance 10-26-02 06:50 PM - Post# 132322 In response to grumpyvette the best way is to use a dial indicator and move the pair of rods back and forth on the crank and take a reading. Technician B says some floating wrist pin designs use a bushing on the small end of the connecting rod. You should also check crankshaft end-play with a dial indicator - too much play and it's likely a worn main thrust bearing. If connecting rod side clearance is excessive, a new rod and bearing cap must be installed. This clearance is a double-edged sword since tighter operating clearances increase the load carrying capacity but reduce oil … Use some feeler gauges and measure the clearance at 12, 3, 6, and 9 o'clock. Too little and piston wall, oil splash is reduced. Onovakind67 mentions added windage with too much clearance. When damage to a rod bearing … One of the first considerations even with stock pins is the clearance to the connecting rod. 0:40. Connecting Rod Side Clearance - Duration: 8:13. Crankshaft Bearing Clearance And Oil Consumption. Remember your piston skirts and wrist pins are splash oiled! 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