Engine breakin? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

Als454 · 06-10-2002, 01:55 AM

Hey Guys, July 4th I plan on firing up my 454 for the first time since complete rebuild. I've been priming the oil and turning it over by hand for several months. I would appreciate any suggestions and how to properly break it in after startup. Also the transmission (TCI automatic) is new.

Thanks in advance

bowtie · 06-10-2002, 02:13 AM

Use 20w50 oil and change it after the first 500 miles. Drive at different speeds ie 30 mph --> 60mph and back, never at a constant speed. When they primed my engine they used a special tool /drill and primed it through the distributor shaft for a couple of minutes. Its really important to make sure you have properly lubed it up before you fire it up. This will determine how long it lasts.

**GMCPaul** · 06-10-2002, 06:36 AM

Run the motor at 2000RPM and above alternating RPMS for at least 20minutes. This is to break in the cam and seat the lifters to it. By alternating the RPM's above 2000 you create greater oil splash helping to make sure you don't have a dry lobe. If you don't do this you will grind a lobe or 2 off cam normally. Immediately after cam break-in I go and change the oil&filter ( you get alot of metal in oil breaking in cam. Then I recheck everything for proper timing, fluid levels and leaks and go for a 200-250 mile drive. Try to stay out of town and alternate RPM's on drive as much as possible. I then change my oil again after 250 miles. Then drive it normalchanging oil again at 2500 and 5000. Once I hit 5000-10,000 miles I consider the motor broke in and ready to be thrashed to see what performance gains I have made at wide open throttle.
Oil changes at 2500-3000 miles for the rest of the motors life and not over revving and causing valve float will help to insure that you get 200,000-250,000 miles out of the motor.
GMCPaul

Als454 · 06-10-2002, 11:28 AM

I've been running the oil pump with a primer I bought from Summit Racing. My question is how much of the engine is actually being oiled? Does the engine have to turn over for oil to reach the top of the heads.

**GMCPaul** · 06-10-2002, 12:03 PM

By using the primer tool it allows oil to reach everything except the lobes on camshaft and the timing chain, lobes on camshaft only receive oil by a splash effect, and timing chain you need to drill a oil in front plug before installing cover for it to receive oil.
But yes rockers and lifters are receiveing oil if you use a oil pump priming tool.
GMCPaul

chevyhouse · 06-10-2002, 12:16 PM

i just finished installing the 388 in my truck yesterday, so far i have done the20 min cam run in, changed the oil and made about a 20 mile drive, i can't begin to tell you how nervous i am hoping everything is right and that this baby will last. we also primed it for a few min before the start. GMC Paul, i used napa premium 10w40 because i read somewhere not to use synthetic and i couldn't find anything detergent free like i had also read. i plan on switching to mobil one after the first 500 miles, any suggestions? the motor is a pretty hot build and will be doing alot of in town driving.

speeddemon · 06-10-2002, 09:20 PM

You want to use a nondetergent oil durring break-in. Alot of your off the wall oil are detergent free. Run the engine above 2500 rpm for 20 min. Then change the oil. The rings will normally seat by 500 miles. After that you can nail it all you want. I would'nt wait for 5,000-10,000 miles that is too long.

Als454 · 06-10-2002, 09:44 PM

Thanks for the imput Guys! I only got one shot at this just. Might as well do it right the first time.

06-10-2002, 01:55 AM	#1
Als454 Senior Member Join Date: Jan 2002 Location: Vienna, Ohio, USA Posts: 259	Engine breakin? Hey Guys, July 4th I plan on firing up my 454 for the first time since complete rebuild. I've been priming the oil and turning it over by hand for several months. I would appreciate any suggestions and how to properly break it in after startup. Also the transmission (TCI automatic) is new. Thanks in advance __________________ 72 Chevy A/C P/B P/S Tilt 454 Engine 400 TCI Trans C30 Frame C10 Suspension Short Wheel Base (Dually)

06-10-2002, 02:13 AM	#2
bowtie Senior Member Join Date: Dec 1999 Location: Saskatchewan Posts: 1,050	Use 20w50 oil and change it after the first 500 miles. Drive at different speeds ie 30 mph --> 60mph and back, never at a constant speed. When they primed my engine they used a special tool /drill and primed it through the distributor shaft for a couple of minutes. Its really important to make sure you have properly lubed it up before you fire it up. This will determine how long it lasts. __________________ ~70 GMCprostreet swb 396/700r NOS 575 hp "the Brick" ~72 chev swb w/68 front clip "GM Millenium corvette yellow" I use and accept Paypal

06-10-2002, 06:36 AM	#3
GMCPaul Senior Member Join Date: Mar 2000 Location: Rockville,In. USA Posts: 3,718	Run the motor at 2000RPM and above alternating RPMS for at least 20minutes. This is to break in the cam and seat the lifters to it. By alternating the RPM's above 2000 you create greater oil splash helping to make sure you don't have a dry lobe. If you don't do this you will grind a lobe or 2 off cam normally. Immediately after cam break-in I go and change the oil&filter ( you get alot of metal in oil breaking in cam. Then I recheck everything for proper timing, fluid levels and leaks and go for a 200-250 mile drive. Try to stay out of town and alternate RPM's on drive as much as possible. I then change my oil again after 250 miles. Then drive it normalchanging oil again at 2500 and 5000. Once I hit 5000-10,000 miles I consider the motor broke in and ready to be thrashed to see what performance gains I have made at wide open throttle. Oil changes at 2500-3000 miles for the rest of the motors life and not over revving and causing valve float will help to insure that you get 200,000-250,000 miles out of the motor. GMCPaul __________________ Secure Online Catalog for-GMCPauls Truck Parts Email- GMCPAULS@GMAIL.COM

06-10-2002, 11:28 AM	#4
Als454 Senior Member Join Date: Jan 2002 Location: Vienna, Ohio, USA Posts: 259	I've been running the oil pump with a primer I bought from Summit Racing. My question is how much of the engine is actually being oiled? Does the engine have to turn over for oil to reach the top of the heads. __________________ 72 Chevy A/C P/B P/S Tilt 454 Engine 400 TCI Trans C30 Frame C10 Suspension Short Wheel Base (Dually)

06-10-2002, 12:03 PM	#5
GMCPaul Senior Member Join Date: Mar 2000 Location: Rockville,In. USA Posts: 3,718	By using the primer tool it allows oil to reach everything except the lobes on camshaft and the timing chain, lobes on camshaft only receive oil by a splash effect, and timing chain you need to drill a oil in front plug before installing cover for it to receive oil. But yes rockers and lifters are receiveing oil if you use a oil pump priming tool. GMCPaul __________________ Secure Online Catalog for-GMCPauls Truck Parts Email- GMCPAULS@GMAIL.COM

06-10-2002, 12:16 PM	#6
chevyhouse BEER-Vacation in a can... Join Date: Jun 2001 Location: wichita, ks Posts: 444	just did mine yesterday i just finished installing the 388 in my truck yesterday, so far i have done the20 min cam run in, changed the oil and made about a 20 mile drive, i can't begin to tell you how nervous i am hoping everything is right and that this baby will last. we also primed it for a few min before the start. GMC Paul, i used napa premium 10w40 because i read somewhere not to use synthetic and i couldn't find anything detergent free like i had also read. i plan on switching to mobil one after the first 500 miles, any suggestions? the motor is a pretty hot build and will be doing alot of in town driving. __________________ Kurt 03' Trailblazer 69' C10 "SPSHL-K", 388 stroker/BTO 700R4, 2400 stall, 3.73 posi, lwb, fleetside long box, 3.5"/5" drop, 18" Budnik 2000 Yamaha V-Star 1100 Custom For Sale-87' V10-4x4, 408/700r4, 4.10's PM for pics

06-10-2002, 09:20 PM	#7
speeddemon Registered User Join Date: May 2002 Location: lexington,South Carolina Posts: 158	You want to use a nondetergent oil durring break-in. Alot of your off the wall oil are detergent free. Run the engine above 2500 rpm for 20 min. Then change the oil. The rings will normally seat by 500 miles. After that you can nail it all you want. I would'nt wait for 5,000-10,000 miles that is too long. __________________ 69-C10 LWB 71- fleetside shortbed It's a shame stupidity isn't painful Never play leapfrog with a unicorn

06-10-2002, 09:44 PM	#8
Als454 Senior Member Join Date: Jan 2002 Location: Vienna, Ohio, USA Posts: 259	Thanks for the imput Guys! I only got one shot at this just. Might as well do it right the first time. __________________ 72 Chevy A/C P/B P/S Tilt 454 Engine 400 TCI Trans C30 Frame C10 Suspension Short Wheel Base (Dually)



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