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First startup after engine rebuild procedure?

Old 11-20-2017, 11:36 AM
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Join Date: Oct 2016
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Default First startup after engine rebuild procedure?

Alright, so after about a year of work, I've just about finished my engine rebuild and installation. Having never rebuilt an engine previously, what all do I need to just before I start the engine up? I've read some generic posts about priming the oil pump, or putting some oil or whatever through the spark plug holes and filling the block with coolant directly (Heater core is what was mentioned), but I've not come across anything specific to our 2.5L engines.
So what's the process? My block is sitting dry but I'm putting fluids in it later today or tomorrow
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Old 11-20-2017, 01:24 PM
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some folks like to pour oil down the oil filter holes (with filter removed) to try to "pre-fill" the passages with oil...if there's already oil in the passages, when the pump kicks in and starts making pressure, it'll be less time until the full engine has oil pressure/flow since there's already oil in the system.

i like to pull either/both the wire from ign. coil to distributor and/or the fuel pump fuse and use the starter to crank over the engine for 10-15 seconds at a time to get oil pumping. then reconnect to fire.

coolant...just fill the coolant tank, on a 944 8-valve the coolant goes from the tank to the passenger side of the radiator, youll have to keep topping off as it gets sucked down. eventually the radiator will be full and it'll start to fill up the lower rad hose, up to the pump and into the block a little. a little messy cheat trick is to remove the upper radiator hose and pour coolant/water down the coolant outlet neck - this will "pre-fill" the head and block with coolant, just fill it until you can see coolant coming up the neck and then re-connect the upper hose so none leaks out.

put the front of the car up 12" or more if you can, open the heater valve to max, leave the coolant tank cap off and run the car, just let it idle is fine, keep topping off the coolant tank as it gets sucked down more. as the temperature starts to come up, crack the 12 or 13mm head bleeder screw on that coolant outlet neck (upper rad hose connection) and let the steam out. just keep running the car and adding coolant until a steady stream of coolant starts coming out that screw, then close it and wipe up the leaked coolant, engine should be bled fine at that point.
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