Lincoln BA5Z-6108-L Piston

Feel for a ridge at the top limit of ring travel with your fingernail, 1/4 inch down from the top of each cylinder; if you feel ridges due to carbon build-up or cylinder wear, those must be relieved with a specific tool to avoid piston failure. When you do away with the ridges, position the engine in such a way that the crankshaft is on the upper end. Always measure the connection rod bearing cap endplay with feeler gauges before unplugging the main bearing cap and the connecting rods bearing cap to ensure that the end play is within the standard service limit of 0.005- 0.015 inch. To prevent confusion, mark the connecting rods and caps appropriately and then, remove the connecting rod cap bolts in equal intervals to come out with the number one connecting cap and bearing insert; do this carefully in order not to drop the insert. Extract the connecting rod/piston assembly through the top of the engine and, if required, knock it out using a wooden or plastic hammer handle for the decision on the next cylinders. Return the connecting rod caps and bearing inserts back to its position with the old inserts to guard the surfaces. Examine the pistons and the connecting rods; follow/verify the ring end gaps so that the piston ring side clearance is appropriate. Lean the piston/connecting rod assemblies and the new ring sets in a way that will allow matching when assembling the engine. Place the top ring into the first cylinder, align it with the walls, and check the end play with a feeler gauge, the variation must be within the range. When the gap is too small, the ring ends should be slowly filed down to increase the gap size; the gaps that are too large need to be assessed for the correctness of the ring type. This is done for all rings and the rings are then fitted to the pistons in their correct positions starting with the oil control ring and other rings in the middle and on top. Before the assemblies are fitted, it is recommended that cylinder walls are cleaned and edges chamfered, and the crank-shaft fitted. Remove the carbon build up from the bearing surfaces, replace bearing inserts without any form of lubrication and ensure that the gap is correctly sited for the piston rings. coat the piston and rings, place a ring compressor and then placing the piston into the cylinder tracking on the piston should be done correctly. Inspect the connecting rod bearing oil clearance using Plastigage, if the marks overlap, the clearance should be in range. If not, ascertain cleanliness then the diameter of the journal to warrant new bearing inserts. Scrape of the remains of Plastigage, lubricate the faces of the bearing, and screw the rod cap with new bolts to the tightened measure. The same should be done for all assemblies with attention to cleanliness and proper orientations then rotate the crankshaft so as to check for bind then checking the endplay of the connecting rod end and in the event that there is a need for resizing then do so.

On 2.7L engines, install the engine block skirt stiffener. On 3.5L and 3.7L engines, install the main bearing cap support brace.

Check the connecting rod endplay as described in Step 3. If new rods or a new crankshaft were installed, the endplay may be inadequate and the rods may need to be resized at an automotive machine shop.

Lubricate the piston and rings with clean engine oil and attach a piston ring compressor.

It may result in piston breakage.