Jeep Engines - Oljeep

41 8 MOPAR PERFORMANCE PARTSTroubleshootingA thorough road test and check of minor carburetoradjustments should always precede major carburetorservice. Specifications for some adjustments are listed onthe Vehicle Emission Control Information label found ineach engine compartment.Many performance complaints are directed at thecarburetor. Some of these are a result of loose, misadjustedor malfunctioning engine or electrical components. Othersdevelop when vacuum hoses become disconnected or areimproperly routed. The proper approach to analyzingcarburetor complaints should include a routine check ofsuch areas.1. Inspect all vacuum hoses and actuators for leaks.2. Tighten intake manifold bolts, carburetor mountingnuts, and isolator mounting bolts to specifications.3.4.5.6.7.8.9.10.11.12Perform cylinder compression test.Clean or replace spark plugs as necessary.Test resistance of spark plug cables. Refer to IgnitionSystem Secondary Circuit Inspection, ‘ElectricalSection’ of the service manual for complete procedure.Inspect ignition primary wire. Test coil output voltage,primary and secondary resistance. Replace parts asnecessary. Refer to ‘Ignition System’ section of theservice manual for complete procedure, and makenecessary adjustment.Reset ignition timing.Check carburetor idle mixture and speed adjustment.Test fuel pump.Remove air cleaner filter element and blow out dirtgently with an air hose. Install a new air filter elementif necessary.Inspect crankcase ventilation system.Road test vehicle as a final test.CleaningThere are many commercial carburetor cleaning solventsavailable which can be used with good results.The choke diaphragm, choke housing assembly, and someplastic parts of the carburetor can be damaged by solvents.Avoid placing these parts in any liquid. Clean the externalsurfaces of these parts with a clean cloth or a soft brush.Shake dirt or other foreign material from the stem (plunger)side of the diaphragm. Compressed air can be used toremove loose dirt but should not be connected to thevacuum diaphragm fitting.If the commercial solvent or cleaner recommends the use ofwater as a rinse, “HOT” water will produce better results.After rinsing, all traces of water must be blown from thepassages with air pressure. Never clean jets with a wire, drill,or other mechanical means, because the orifices may becomeenlarged, making the mixture too rich for proper performance.When checking parts removed from the carburetor, it is attirnes difficult to be sure they are satisfactory for furtherservice. It is therefore recommended that in such cases, newparts be installed.Caution: The practice of priming an engine by pouringgasoline into the carburetor air horn for starting afterservicing the fuel system should be strictly avoided.Cranking the engine, and then priming by depressing theaccelerator pedal several times should be adequate.Diagnosing carburetor complaints may require that theengine be started and run with the air cleaner removed.Warning! While running the engine with the air cleaner itis possible that the engine could backfire. A backfiringsiluation is likely to occur if the carburetor ismalfunctioning. DO NOT place your hands or face on,over, or near the carburetor while the engine is being startedor running. Severe personal injury may occur.INTAKE MANIFOLDOnce carburetion and engine applications are known, thebest intake manifold can be selected. For drag and ovaltrack racing vehicles it is recommended that the heat(exhaust) cross-over in the intake manifold be blocked byeither putting shims in the gasket, or by brazing a metalplate into both sides of the cross-over in the intakemanifold. (The best shim material is thin stainless steel.)With the heat cross-over blocked, the choke will no longerfunction. The carburetor will usually have to be rejetted forracing. Blocking the heat cross-over usually causes thevehicle to run poorly when dead cold, which is why it isrecommended for racing vehicles only. It also should not beconsidered for cold weather use. Not required on cylinderheads that have no heat cross-over.Intake Manifold GasketTlhis intake manifold gasket can be used with productioncast iron or aftermarket aluminum intake manifolds.DaimlerChrysler engineered and approved. For 360 AMCV-8 engine only.Pi452963 1 Intake manifold gasket.