engine break-in techniques hows, whys, and suggestions?

sdiesel

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fellas,

i'm close to start-up on the ranch truck
any comments experiences and suggestions helpful.

honestly i have not done many of these start ups. beings a n engine lasts a long time

how do u-all go about your first start ups


My particular concern is i built the motor two years ago; i hope i remembered to do everything right!
 
On a flat tappet camshaft, I use decent oil(not energy saving) and then a break in additive. Start engine, 2000rpm idle for 20 minutes. Shut it off and let it cool.

Change oil, drive easy for 750 miles, drive normal for the next 250, then change oil and call it broken in.
 
Flat tappet cams need to be "broken in" and they do so by wearing there respective parts together when the engine is first run. That break in period is the most critical time in the cams life because of the parts wearing together, and if it is not done correctly, the cam can develop a "flat lobe" and will be ruined. The cam assembly lube that is applied to the lobes upon installation will keep things lubed and safe for just the first few seconds of the cams life, after that it will be wiped away and the cam will need the engine oil to keep it happy from that point on. Cam/lifter lubrication is achieved by oil "splashing" and that is the need for the higher rpm during break in as there is next to zero oil splashing taking place at idle.

Another major concern is that virtually every engine currently produced and the majority of the engines on the road today are equipped with roller cams and lifters that do not require the expensive additives that flat tappet cams do so the oil companies have removed these agents, primarily zinc, from their formulas as it is no longer widely required. The reason you need a break in oil or an additive while first firing the engine is to ensure that there is sufficient zinc in the oil to properly "break in" the cam. Once the cam and lifters have worn together, regular old modern oil is usually good to use for our old stuff, ONCE IT IS BROKEN IN. If you have crazy valve spring pressures or other high loads on the cam/lifter you should continue to use better oil thereafter as well.
 
very helpful explaination here thank you

can i put some very light oil in the spark plug holes b4 start up so the rings have a slippery surface to ride on?
 
Can't see that a little oil in the cylinders would hurt anything if it's been sitting a while.

More importantly however is to double and triple check your distributor settings and ensure there is fuel in the carb and that it will function correctly. You want the engine to fire immediately and to begin the cam break in. If there is a silly mistake like having the timing off or an empty carb, dead fuel pump, missing vacuum line etc., the engine will crank and crank until all the cam assembly lube is scraped off the lobes and they no longer have that protection and a cam may be lost because of it. If the engine does not fire immediately, stop and look for the problem.

This has been public service message. 8)
 
Make sure your lifter bores are all clean and free of varnish, and pre lubed. the lifters need to rotate freely, can wipe a new cam pretty quick if one is sticky. I dont know about you guys but i was always told the first 20 minutes you want to vary rpms 1500-2000 a bit to promote lifter rotation.
 
if the engine has sat awhile or it is new (or both)

pull the hexagonal drive shaft out of the bottom of the distributor
attach the hex shaft to a 5/16" socket... it will have a spring retainer clip on the distributor end... and put it on a long extension and put it back down into the engine block into the oil pump drive.
use an electric drill to run the oil pump up to pressure for a couple minutes until oil starts coming out of the pushrods on the top end

even better, get a buddy (or moderately willing wife) to run the drill while you turn the engine over with a socket on the damper bolt. I'd say 20 complete engine rotations minimum, but that might be overkill.


The cam thing is important but it becomes more important with stiff valve springs and high lift cams... i think on our engines, the chance of wiping a cam lobe is pretty minimal.

IE: ford probably just started these up and drove them off the assembly line without any kind of sophisticated break-in procedure.
 
Reviving this older thread on Initial fire-up and break in' is reasonable considering how many trouble in paradise posts after fire ups'.

I completed the assembly of the turbo project 250 and instead of working in a car, decided to fire-up and run-in' on a stationary engine stand. The engine is a stock 250 block (@ 35K miles) with the Head re worked with V8 springs, back cut valves etc, but no milling to retain 62cc chambers for a SCR around 7.81 with a modern composite head gasket. Cam is still OEM with Lunati lifters and adj. ' rockers. Liberal assembly lube, cam guard and oil pump priming before adding HEI ignition and cooling accessories to fire it up.

1st attempt: Started on less than a full revolution with OEM 'Maverick YFA and ran fairly well through a suitable cam/lifter part throttle sequence. BUT , coolant leaked from defective heat sensor, VC leaked a bit and the carb stumbled and missed on throttle.

2Nd attempt : A known good YF from a maverick 170 adapted to the 250 ran excellent and made me confident carb was problem but is too small for the 250. Adapted a good running 2300 350 CFM and found the accel pump leaking onto manifold (Gasahol?). Next the planned Turbo prepped QuadraJet from the Buick Turbo V6 once it's cleaned and rebuilt ...

The run stand has a spare radiator from my '50, a Mercedes elec fan,the motor has FW clutch and toploader 3.03 to complete the setup.

have fun

. . . .
 
engine break-in techniques hows, whys, and suggestions?
continued...

break-in and run-up of 250 six turbocharger project proceeds two steps forward and a step or stumble back...

3rd Attempt: : Initial fire up the rockers hit the valve cover throwing a scare into me until figgered out' (relieved VC baffles with the BFH...)

> Assembling the 250 I found the adjustable rockers are at the end of adjuster - screwed OUT to ball end like the pusrods are too long. I can't account for this as the Cyl Head was specifically NOT MILLED to retain 62 cc chambers and I cleaned and blue printed the block. . My machinist (for 40 years) left surface intact after we measured no appreciable warpage/deflection .
Pushrods are spec @ 9.350 length and head gasket is modern composite ( @ .040 ) which should make head higher . Engine runs fine for over an hour total so far but will probabbly have set of Pushrods built to center adjusters more typically. Just one of those Ford things ? .


'started adding the Turbo setup adapted from Buick 3.8 , it's a Draw-Thru carbureted setup usiing OEM application big 4Bbl and simple turbo routing with home machined adapter , also adding mechanical brackets and vacuum/boost and A/f, oil pressure at turbo and fuel pressure guages .




have fun
 
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