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Discussion Starter #1
Well this is my first engine rebuild and after I prime the oil system it'll be ready to start up. Is there anything I ought to be aware of, and any techniques for initial startup once it's running? Should I be at 0 degrees TDC or at 10 degrees BTDC?
It's a 1977 400 bored .030 over with a lunati cam and 142 heads. Compression should be right at 9.3. It had a points distributor for some reason, so I put in a crane xri electronic conversion.


B. Co. 1-22 Infantry 4th Infantry Division OIF 2008-09
 

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My experience has been to pre lube the engine, remove distro and turn the oil pump to build oil pressure, hand turn the engine and repeat. Next when it fires, there will be a lot of smoke :lol: and the temperature will climb quite fast as it breaks in, oil spilt around the engine will smoke, exhaust if new will odorize the area. Keep an eye of the oil pressure, fluid leaks and temperature during the cam break in. I kept a timing light connected to monitor the timing, slightly tweaking and at the same time adjusting the carbs, expecially if they are new or rebuilt. Its 15-20 minutes of real excitement. :willy:
 

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Check around the exhaust and moving parts for any wires, hoses and ect.. touching them. Give everything the wiggle test to see if anything will move onto hot or moving parts. AND check the heat crossover in the intake manifold for wires and vacuum tubes laying across it, it gets hot enough to melt stuff and start small fires....ask me how I know.:mad:
 

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Discussion Starter #6
Setting it to 6 degrees BTDC is literally turning the crank to the 6 degree mark correct? Am I took hook up the vacuum advance hose after its reached operating temp? The cam is brand new. My Lemans doesn't have actual oil pressure or temp gauges, would y'all recommend hooking up a set of real gauges.


B. Co. 1-22 Infantry 4th Infantry Division OIF 2008-09
 

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I would hook up oil pressure and temp gauges at least while you break in the new motor.

You can install em temporarily if you don't like how they look or put em in the glovebox or underhood.

Unhooking the vacuum advance is for setting timing only. To start the motor I would leave the dist semi tight/loose so you can turn it by hand and run the motor initially where it "feels" best. After it's running smoothly you can check the timing with a light. As others have said it's that first 15-20 min that is critical.

I hope you have a good exhaust on it and don't piss off your nieghbors :shutme :rolleyes:.

Good luck and have fun. :D
 

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Discussion Starter #8
I'm going to need the correct oil pressure and temp sending units first though arent I? How many quarts does the 400 take? I only got 5 in there before dipstick read full


B. Co. 1-22 Infantry 4th Infantry Division OIF 2008-09
 

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Don't sweat the timing on the first startup. If it runs, it's ok. It's more important for you to break in the cam first - THEN - go back and set the timing. Once it starts, don't let it idle at all --- keep it "around" 2000 rpm for 15-20 minutes (vary it every so often). Might help to set up a big fan blowing into the radiator to help move air. The only reason to shut it down during this period is if "something" happens to make it dangerous to continue - like overheating, bad oil/coolant leak, etc.

Also, if you've replaced valve springs with stronger than stock springs, it's a good idea to remove the inner springs and break in the cam using the outer springs only. Once the cam break in is done, re-install the inners, set the timing, and you should be good to go (assuming no bad problems cropped up).

Bear
 

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Discussion Starter #12
So I'll just set the crank at 6 degrees BTDC and focus on the can break in. The heads did not get stronger springs.
Do I need a additive in the break-in oil for the cam's sake? Amsoil says it already has a high zinc amount.


B. Co. 1-22 Infantry 4th Infantry Division OIF 2008-09
 

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Better safe than sorry. I would grab a bottle of zddp cam break in additive at the local machine or speed shop. Just my .02 had a buddy wipe his cam.
 
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