2ZZ and 1ZZ Engine Install Tips


    • When swapping a 2ZZ engine into your 1ZZ car there are many parts and changes needed- check the page for your MR2 or CELICA on our site for more info before install
    • If you are replacing your engine with one of the same type you should transfer over any needed parts from your old engine before returning it as core or installing the new engine. Important parts to reuse that are specific to your car’s model and year include manifolds, injectors, knock sensor, water pipe. On used 1ZZ engines make sure that the cast engine mount that bolts to the timing cover is the right type for your vehicle, you may need to swap it. This applies to factory supercharged Lotus 2ZZ cars as well.
    • In both 2ZZ and 1ZZ engines, if installing or replacing water pump, be extremely careful with bolt length. The original water pump that came with your car from the factory probably had 4 thin bosses (B) and 2 thicker ones (A). The two thicker ones are for bolts that only secure the water pump to threaded holes in the timing cover. The other 4 pass through the front cover and thread into the engine block. Later model OEM pumps and some aftermarket replacement pumps have all 6 bosses the same thinner thickness. That means if you reuse all of your water pump bolts, two will be too long. The consequence is they collide with the engine block once installed and pry the timing cover away from the engine block, allowing oil and coolant to mix. BAD. The (B) bolts should be 35mm long, measured from under the head (UHL). If you have the older style water pump with two different thicknesses then the (A) bolts should be 30mm UHL. If you have the water pump with all 6 bosses the same thickness then the (A) bolts should be 20mm UHL.
    • Pay attention to how you hook up the vacuum lines and coolant lines especially near the throttle body. If you mix them up you’ll have air in your cooling system and worse you’ll have coolant in your intake manifold. Sloppy mechanics will mistake this for a bad head gasket and say the engine is no good. This can cause severe engine damage.
    • We strongly recommend installing new spark plugs in used engines. New engines are shipped without spark plugs.
    • The 1ZZ and 2ZZ engines can both have rod bearing problems even at reasonable power levels. First, run Mobil 1 or equivalent synthetic oil. We recommend 5W30 for average applications and 10W40 or 15W50 for high boost or road race applications. Watch oil temps if you’re running at high RPMs for extended time periods; the Celica, Matrix, Corolla and MR2-S have no oil cooler.
    • Be sure to check that the oil pump does prime and supply adequate oil pressure before or within a couple of seconds after starting the engine for the first time. It’s recommended that you crank the engine with the starter without starting it (remove ECU fuse) until oil pressure registers. Especially critical on a new or rebuilt engine.
    • Oil pick-up is also a problem. If you’ll be pulling high lateral g’s on sticky tires we strongly recommend the use of a MWR Moroso 6-quart oil pan. This pan has a higher capacity and internal baffling which prevent the engine from having problems in those long corners. You may also want to consider an MWR Accusump Kit for your road race Lotus.
    • The 1ZZ and 2ZZ coolant systems are notoriously hard to prime. By far the best solution is a Vacuum Fill kit (sold separately) which allows you to evacuate the air from the system before filling with coolant. Whether you use that or not, the engine should be started with the coolant reservoir full and held 1-2 feet above its normal location. This will help the water pump suck coolant in and start circulating it. Be sure that you can see coolant exiting the small tube(s) into the top of the bottle. Also check that your heater blows heat and that the radiator hoses feel hot once the engine gets up to temperature. Failure to do so can cause the engine to overheat quickly even without any indication on the coolant temp gauge. Watch for air bubbles and overheating the first couple of times operating the engine- coolant flow should be confirmed at the bottle several times and coolant added if necessary.
    • Go easy on a freshly built the engine for the first 200 miles. Keep it under 6000rpm. Change the oil and filter at 100 miles. Oil fill and filter change is required during install for all used engines.