Genuine 1995 Jeep Wrangler Camshaft

1995 Jeep Wrangler Camshaft Parts Questions & Experts Answers

• Q: How to determine the extent of cam lobe wear and perform a camshaft and Camshaft Bearing replacement in 2.5L four cylinder engine on 1995 Jeep Wrangler?

  A: To find out the level of wear of the cam lobe, one should measure the lobe lift before the removal of the camshaft, with the number one piston on the TDC on the compression phase. Bolt a dial indicator on the engine in a position which will allow to place the plunger of the indicator on the top part of the first rocker arm above the pushrod. Centre the dial indicator on the investigating cam lobe and rotate the crankshaft slowly in the normal direction of rotation until the indicator needle no longer increases and turns in the opposite direction, while noting maximum lift of the cam lobe. Perform the same for the other values with each piston at the top dead center on the compression stroke and also firing order sequence as mentioned before. Once all the checks are done, make a comparison with the specifications and if camshaft lobe lift is lower than the standard value , replace the camshaft. I would remove the negative cable from Battery, remove the existing radiator and depending on the model for, vehicles with air conditioning; there is no need to disconnect the refrigerant lines; but unbolt the compressor. For the vehicles with carburetor, first remove the fuel pump and distributor, if have not removed the valve cover already. I would take out all the rocker arms, pushrods, hydraulic lifters, timing chain and sprockets since if the camshaft looks to have rubbed the timing chain cover then the oil pressure relieved holes in the rear cam journal should be checked for debris. After that install the bolt at one end of the camshaft so that it can be turned into a handle and then pull out the camshaft cautiously from the block supporting it near the block so that the bearing are not spoilt. Subsequent to removal, the camshaft should be cleaner in solvent and the bearing journals should be checked for wear, pitting and seizure; if signs of these are evident then the camshaft and bearings will need replacement. If the journals are good, then take the micrometer and read the dimensions as well as look out for conditions such as high wear or out-of-roundness. Using a telescoping gauge and a micrometer check the inside diameter of each camshaft bearing subtracting the cam journal diameter from the bearing inside diameter to get the bearing oil clearance, comparing it to the standards and replacing if necessary with new bearings. Check the distributor drive gear as to their condition and replace the camshaft if seemed to be bad. Inspection for damaged camshaft lobes includes discoloration, score marks, chipped areas, pitting, and uneven wear; if the lobes are intact and if measurements indicate it as such, the camshaft can be reused. Because of this, bearing replacement needs extra tool work and skills , so it is best to take the engine block to an automotive machine shop. For installation use moly-base grease or engine assembly lube on the camshaft bearing journals and lobes then place the camshaft into position in the engine block and while doing this the installer should support it either from the block as this can cause scraping of the bearing. Loosely fit the camshaft sprocket on the camshaft and rotate it to align the timing mark with the centre line of the crank, then take off the sprocket. Replace all other parts in the reverse order of removal and ensure that the lifters get fitted back to their positions if the original camshaft and lifters are being rebuilt, else fit new lifters if a new shaft is being used. Last but not the least, pour some coolant, replace the oil and filter besides switching on the engine to check for the presence of any leaks or unusual sounds, check the ignition timing.