How to prep and start a rebuilt engine

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==Oil==
 
==Oil==
Oil formulations are being changed due to pressure from the OEM's and EPA. Zinc and phosphorus tend to coat O2 sensors and plug catalytic converters resulting in warranty claims as well as contributing to dirty exhaust emissions, so they are being eliminated from motor oils as we speak. These elements were used in the oil to provide extreme pressure lubrication and protection from galling on heavily loaded engine components such as the cam lobe/lifter crown interface. The oil companies have no choice, they have to follow the guidelines imposed on them.
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===Break in oil===
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Use a good quality 30w for break in along with an additive made specially for break in like ZDDPlus. There are also good break in oils available that already contain the right amounts of additives.  
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;30w break in oil
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*Amzoil
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*Brad Penn/Howards Cams
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*Lucas
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*Edelbrock
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There are also multigrade break in oils. Royal Purple and Comp Cams' break in oil is 10w-30. Joe Gibbs break in oil is heaver (15w-50), but still a multigrade. I'm sure there are others. Plus there are those who use over the counter multigrade motor oil w/ZDDPlus, etc. added.
  
The loss of those high pressure lubricant suppliments from the motor oil now available had less impact on newer engines because of the change to roller cams. With them, there is no special procedure for break-in. You just oil the lifters, drop them in and no other special break-in procedures are needed for the cam and lifters. Obviously the rings and other new components will still require a break in period, but with a roller cam the biggest problem associated with breaking in a rebuilt engine (flat tappet cam lobe/lifter failure) is a thing of the past.
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At the end of the day it's more important to build the engine right and set it up to fire up immediately after priming the oiling system than to worry ''too'' much about the viscosity. But there are not many who will recommend using too thin of a viscosity, like 10w-30/15w-40 for break in.  
  
There are specialty/racing motor oil that will give protection to your new flat tappet cam and lifters. Generally speaking, "over the counter" motor oils are not up to the task; they are constantly changing formulations, so what might have been acceptable for use with a flat tappet valve train might not be the next time you look up the specs, so be very careful when selecting motor oil. Crane Cams has recommended Shell Rotella and an engine oil supplement containing extreme pressure lubricants. The other oil that is touted by engine builders is 15W-40 RPM Delo. GM has discontinued (and now have re-released) the EOS (Engine Oil Supplement). If you use a molymndinum disulfide-type cam and lifter break in lube applied to the foot of the lifter and cam lobes along with adding 1-1/2 ounces of ZDDP additive per quart of good quality oil for initial start up, along with allowing no idle time for the first 20 minutes of run time at 2000 plus rpm while varying engine speed, you've done about as well as you can to prevent lifter/lobe scuff/wear/failure. With subsequent oil changes, one ounce per quart of oil should help to contribute to long engine life. Or use an oil formulated with sufficient additives, sold by the aftermarket (Joe Gibbs, Royal Purple, etc.).
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===Oil after break in===
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Oil formulations are being changed due to pressure from the EPA. Zinc and phosphorus tend to coat O2 sensors and plug catalytic converters resulting in warranty claims as well as contributing to dirty exhaust emissions, so they are being eliminated from motor oils as we speak. These elements were used in the oil to provide extreme pressure lubrication and protection from galling on heavily loaded engine components such as the cam lobe/lifter crown interface. The oil companies have no choice, they have to follow the guidelines imposed on them.
 +
 
 +
There are specialty/racing motor oil that will give protection to your new flat tappet cam and lifters. Generally speaking, "over the counter" motor oils are not up to the task; they are constantly changing formulations, so what might have been acceptable for use with a flat tappet valve train might not be the next time you look up the specs, so be very careful when selecting motor oil.  
 +
 
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GM has discontinued (and now have re-released) the EOS (Engine Oil Supplement). If you use a molybdenum disulphide-type cam and lifter break in lube applied to the foot of the lifter and cam lobes along with adding the recommended amount of ZDDP additive per quart of good quality oil for initial start up, along with allowing no idle time for the first 20 minutes of run time at 2000 plus rpm while varying engine speed, you've done about as well as you can to prevent lifter/lobe scuff/wear/failure. With subsequent oil changes, the recommended amount of oil supplement should be added at each oil/filter change in order to have along engine life. Or use an oil formulated with sufficient additives, sold by the aftermarket (Joe Gibbs, Royal Purple, etc.).
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The loss of those high pressure lubricant supplements from the motor oils that are now available have much less impact on newer engines because of the change to roller cams by the manufacturers. With a roller cam, there is no special procedure for break-in. You just oil the lifters, drop them in and no other special break-in procedures are needed for the cam and lifters. Obviously the rings and other new components will still require a break in period, but with a roller cam the biggest problem associated with breaking in a rebuilt engine (flat tappet cam lobe/lifter failure) is a thing of the past. 
  
 
==General recommendations==
 
==General recommendations==
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*Do not break in the cam using the springs that will be eventually run with the cam if the springs are much higher than about 120-130 pounds on the seat at the installed height. Instead, assemble the heads with used '''stock''' springs, ''if they will give enough lift before coil bind''. Keep an old set on the shelf just for running in a new motor, then change them out at the 20-30 minute mark. Another option is to remove the inner springs from a dual valve spring for break in. Replace the inner spring afterwards. Manley makes a lever-type tool for this procedure, to be used with compressed air to keep the valve seated. If you don't have a compressor you can feed thin rope/cord down the spark plug hole with the piston down away from TDC. After the rope is fed in, carefully rotate the engine so the piston is compressing the rope up against the valve head. Do this on the compression stroke. Or have a shop do it. Another way is to use a set of reduced-ratio rocker arms for break-in.  
 
*Do not break in the cam using the springs that will be eventually run with the cam if the springs are much higher than about 120-130 pounds on the seat at the installed height. Instead, assemble the heads with used '''stock''' springs, ''if they will give enough lift before coil bind''. Keep an old set on the shelf just for running in a new motor, then change them out at the 20-30 minute mark. Another option is to remove the inner springs from a dual valve spring for break in. Replace the inner spring afterwards. Manley makes a lever-type tool for this procedure, to be used with compressed air to keep the valve seated. If you don't have a compressor you can feed thin rope/cord down the spark plug hole with the piston down away from TDC. After the rope is fed in, carefully rotate the engine so the piston is compressing the rope up against the valve head. Do this on the compression stroke. Or have a shop do it. Another way is to use a set of reduced-ratio rocker arms for break-in.  
  
*Checking for interference. Nothing will wipe a cam and lifters quicker than mechanical interference in the valvetrain. Check for piston to valve clearance, rocker arm to stud clearance at full lift, spring coil bind (stacking solid) and retainer to valve guide boss clearance at full lift. Also check for pushrod to guide clearance to insure the pushrods are not rubbing or binding. You might have one culprit that you didn't catch, such as a bent pushrod. Roll all pushrods on a piece of plate glass before assembly to insure straightness. See: [http://www.iskycams.com/camshaft.php Installing a Racing Camshaft] and [[Valve train points to check]].
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*Checking for interference. Nothing will wipe a cam and lifters quicker than mechanical interference in the valve train. Check for piston to valve clearance, rocker arm to stud clearance at full lift, spring coil bind (stacking solid) and retainer to valve guide boss clearance at full lift. Also check for pushrod to guide clearance to insure the pushrods are not rubbing or binding. You might have one culprit that you didn't catch, such as a bent pushrod. Roll all pushrods on a piece of plate glass before assembly to insure straightness. See: [http://www.iskycams.com/camshaft.php Installing a Racing Camshaft] and [[Valve train points to check]].
  
 
*Another problem that can occur if you are not diligent in checking tolerances is tight lifter-to-bore clearance. Failure of the lifters to rotate in the lifter bore will gall the lifter crown/cam lobe in short order, and cam and lifter failure will soon follow. Always oil the lifter bores and lifters when doing mock-up and drop them through the lifter bores. With the lifter bores vertical on the engine stand, the lifters should drop through and fall into your hand with oil on them. If they don't, first inspect the oil gallery holes where they intersect the lifter bores for any raised burrs, etc. Then scrub the lifter bores with a shotgun brass bristle brush and acetone/lacquer thinner to remove all traces of shellac. Just running a rag through the bores is not enough. If the bores are still too tight, hone the lifter bores for additional clearance until they will fall through- only do this if all else fails; too much clearance can reduce oil pressure throughout the engine and is not needed in most cases. The cam grinders are beginning to manufacture their lifters with a shorter radius on the crown to assist in lifter rotation.
 
*Another problem that can occur if you are not diligent in checking tolerances is tight lifter-to-bore clearance. Failure of the lifters to rotate in the lifter bore will gall the lifter crown/cam lobe in short order, and cam and lifter failure will soon follow. Always oil the lifter bores and lifters when doing mock-up and drop them through the lifter bores. With the lifter bores vertical on the engine stand, the lifters should drop through and fall into your hand with oil on them. If they don't, first inspect the oil gallery holes where they intersect the lifter bores for any raised burrs, etc. Then scrub the lifter bores with a shotgun brass bristle brush and acetone/lacquer thinner to remove all traces of shellac. Just running a rag through the bores is not enough. If the bores are still too tight, hone the lifter bores for additional clearance until they will fall through- only do this if all else fails; too much clearance can reduce oil pressure throughout the engine and is not needed in most cases. The cam grinders are beginning to manufacture their lifters with a shorter radius on the crown to assist in lifter rotation.
  
*These suggestions are brought to you by John Callies of Callies Crankshaft fame:
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*These suggestions are brought to you by John Callies of Callies Crankshaft:
**Visually inspect for tool chatter and mis-machining.
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**Visually inspect for tool chatter and poor machining.
 
**Clean the shaft with mineral spirits and dry thoroughly.
 
**Clean the shaft with mineral spirits and dry thoroughly.
 
**Use a hand held propane torch and heat the shaft to disperse any moisture.
 
**Use a hand held propane torch and heat the shaft to disperse any moisture.
 
**Spray the cam with graphite. (Another option is to use a dry-film lube made for this)
 
**Spray the cam with graphite. (Another option is to use a dry-film lube made for this)
**Use quality high pressure lube on cam lobes and lifter crowns (molybdenum disulfide black goop that comes with most cam and lifters).
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**Use quality high pressure lube on cam lobes and lifter crowns (molybdenum disulphide black goop that comes with most cam and lifters).
 
**Select a quality lifter since the market is being saturated with offshore lifters that are soft.
 
**Select a quality lifter since the market is being saturated with offshore lifters that are soft.
**Make sure on startup the engine is ready to run at 2000-2500 rpm for 20 minutes. ZERO IDLING FOR 20 MINUTES.
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**Make sure on start up the engine is ready to run at 2000-2500 rpm for 20 minutes. ZERO IDLING FOR 20 MINUTES.
  
 
*Make sure the motor is timed and use a known good carb or other induction system as well as ignition system. The new cam and lifters will not tolerate any grinding on the starter to get the motor fired. They are lubed by splash off the crank at higher engine speeds. Have everything ready to go including having the carb primed with fuel and a fully charged battery.
 
*Make sure the motor is timed and use a known good carb or other induction system as well as ignition system. The new cam and lifters will not tolerate any grinding on the starter to get the motor fired. They are lubed by splash off the crank at higher engine speeds. Have everything ready to go including having the carb primed with fuel and a fully charged battery.
  
*Pre-oil the motor with a drill motor and oil pump primer tool such as [http://www.jegs.com/i/JEGS-Performance-Products/555/23640/10002/-1?parentProductId=754806 this one from Jegs]. Put a socket on the harmonic damper retaining bolt and rotate the motor through at least 2 full revolutions while priming. There are engines (some MOPAR, Chevy Lx-series, etc.) that will be primed easier by using a pressurized pre oiler set-up.
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*Pre-oil the motor with a drill motor and oil pump primer tool such as [http://www.jegs.com/i/JEGS-Performance-Products/555/23640/10002/-1?parentProductId=754806 this one from Jegs]. Put a socket on the harmonic damper retaining bolt and rotate the motor through at least 2 full revolutions while priming. There are engines (some MOPAR, Chevy Lx-series, etc.) that will be primed easier by using a pressurized pre-oiler set-up.
  
*At the end of the 20 minute break-in period, change the oil and filter. Drive the vehicle for 30 miles, altering the speed and letting the motor rev down from 60 mph to 20 mph with your foot off the gas pedal. Change the oil and filter and repeat the EOS again. Change the valve springs to the ones that came with the cam kit. Drive for 500 miles and change the oil and filter again.
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*At the end of the 20 minute break-in period, change the oil and filter. Drive the vehicle for 30 miles, altering the speed and letting the motor rev down from 60 mph to 20 mph with your foot off the gas pedal. Change the oil and filter, using break in oil or added break in oil supplement. If the valve springs were changed, or the inner spring removed for break in, change the valve springs to the correct ones or add the inner spring. Drive for 500 miles and change the oil and filter again. From this point on, use an oil supplement that will provide protection for the flat tappet cam and lifters if that's what is in the engine. This is less than the amount of oil additive that was used at break in.
  
 
==Automatic transmission==
 
==Automatic transmission==

Revision as of 17:20, 30 June 2012

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