Welcome to Bullfrog Motosport!
ARC billet rod with bearing inserts for the Harbor Freight Predator 212cc engine. Fits both the Hemi and non-Hemi versions. 1.188" rod journal and .709" wrist pin. Built from 7075-T651 aircraft grade aluminum. Uses ARC's custom manufactured bearing inserts and ARP rod bolts manufactured specifically for ARC. ARC has the only forced oiling scoop dipper rods available for these engines providing superior lubrication at the bearing journal.
Rod includes bolts & bearings.
Rod bolt torque: 170 in/lbs lubricated
To install your ARC rod you will need a 12 point 1/4" socket and a QUALITY inch pound torque wrench. You will need an outside micrometer, dial bore gauge or plasti gauge, and oil.
Measure the crank pin diameter with the outside mic, it should measure 1.188" +/-.0005". Measure in several spots to insure roundness. If out of round more than .0005" it probably should be replaced. The crank pin finish should be smooth to the touch.
When disassembling the rod notice on the side of the rod with the part number there are two dots next to the separation point of the beam and cap. These dots help to re-orientate the cap and beam when assembled. The side of the rod with the part number engraved will always face the side cover side.
Make sure the bearing and rod serrations are clean and install the bearings. Lubricate the rod bolt threads and hand tighten the bolts. Using the torque wrench tighten the bolts to 60 inch lbs. Alternate each side to increase the torque by 20 inch lbs at a time until you reach 150 inch lbs. Then loosen the bolts and repeat the torque process. this helps seat the rod bearing especially on a new rod. Measure the bore with your dial bore gauge opposite the parting lines. If using plasti gauge you will have to install the rod on the crank and use in accordance the plasti gauge instructions.
The rod bore should measure 1.191 +/.0005". With plasti gauge you are looking for about .003" clearance. From .0025-.0035" clearance is acceptable.
Once clearance is set apply oil to rod, crank, and wrist pin and install this time torque to 170 inch lbs.
Improperly torquing rod bolts is one of the most common causes of rod failure.
Refer to instructions shipped with all rods.