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Anybody got any ideas on how to prime the oiling system on a DOHC motor. The only way I can think of is pullin the spark plugs and crankin the engine. I'm not sure that the startet will crank fast enough to build any pressure. Lookin for some ideas. Just pull the distributor and use a drill on the pump driveshaft......LOL

THANKS
LEE
 

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If you hold the gas pedal to the floor the car will crank but not fire up. Thats how I did it with my PI, but the DOHC may be (probably) a different animal.
 

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If you hold the gas pedal to the floor the car will crank but not fire up. Thats how I did it with my PI, but the DOHC may be (probably) a different animal.
You are not the first person to say that so I think that's what I'll do. I just thought pullin the plugs would unload everything and give it a few more RPM's to build pressure.

Thanks
Lee
 

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Do not do that! Your car might fire up and boom goes the motor, trust me I've watched it happen. Unlplug the coils, and pull the fuse for the fuel pump then crank it for 30 seconds, off ten then repeat a few times, do this with a battery charger on the car so you don't sap the battery. The RPMS of the starter will be plenty enough to build oil pressure and will help seat the piston rings. That's the correct way to do it.
 

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If I don't borrow my engine builders primer. Then I like to do what you are thinking. Pull the plugs so there is less pressure on the bearings and I also unhook the crank and cam sensors and trip the inertia switch so no fuel sprays or plugs try to fire then crank it with the starter.
 

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I just replied to your PM, Lee. Here's what I use to prime new engines before the first firing.



The Accusump is just for priming the engine in the XR7 before regular startup. It doesn't have enough capacity to fully prime a fresh rebuild. Like I said, on your setup, you could prime through the oil sending unit port, or the port directly below it.
 

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I have a relocation kit for my filter, can I just plug the port from the sump into the hose that goes to the block to do the same thing to prime it?

Second, what is a good break in oil for a new 4.6 and how long until you change it out for regular oil?
 

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I just replied to your PM, Lee. Here's what I use to prime new engines before the first firing.
...
The Accusump is just for priming the engine in the XR7 before regular startup. It doesn't have enough capacity to fully prime a fresh rebuild. Like I said, on your setup, you could prime through the oil sending unit port, or the port directly below it.
That is a lot cheaper than an accumulator, as well. :D

I've used a filled accumulator, pressurized with air, to bring up oil pressure on several engines over the years...

It's especially nice to do before you start timing heads. :)
 

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I have a relocation kit for my filter, can I just plug the port from the sump into the hose that goes to the block to do the same thing to prime it?

Second, what is a good break in oil for a new 4.6 and how long until you change it out for regular oil?
Yes.

Viscosity will depend on your clearances, but you'll likely want to use a conventional 5W-30 oil for break-in. I'd suggest changing it after seating the rings, then again after 500 miles. At 1,000 miles you should be able to switch to synthetic. Of course, this depends on what ring material you're running, too.


That is a lot cheaper than an accumulator, as well. :D

I've used a filled accumulator, pressurized with air, to bring up oil pressure on several engines over the years...

It's especially nice to do before you start timing heads. :)

Yep. The bug sprayer method works really well for how little it costs. My little 1-1/2 quart accumulator is perfect for bringing the engine up to ~25 psi before firing, but a fresh build requires a heck of a lot more pressurized oil than that to fully prime it.
 

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With some newer engines this is true, its called clear flood mode. I've done it and I've watched other people do it, bottom line is why risk it? Unplug a few connectors and pull a fuse or two, it only takes a few minutes as opposed to nuking a motor and having to spend a couple of hours pulling it and reinstalling one. Also explain to me how cranking and engine will not builld pressure, since the oil pump is mounted on the crankshaft, and what spins the when you crank the motor? That's right the crankshaft, you will build pressure, not the ammount you need when then engine is running, but enough to oil the engine and all its moving parts. I only do this for a living, but what do I know right?
 

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Holding the accelerator to the floor is the standard way to clear an engine from being flooded with gas.

A carb engine won't build vacuum, so no major gas; the computer emulates this for us because it's always worked. :)

As long as your TPS and wiring are perfect, there's no worry whatsoever with using that method to keep your new engine from starting.

Of Course, if the TPS intermittently fails, or you twitch your foot, it starts at wot. :)

On a 96-97 4.6 car, pulling fuse 15 in the box under the hood will prevent the eec from working.

This prevents the coils from firing; I don't think the injectors fire. YourCarMayVary.
 
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