Burn in interrupted
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Joined: Sep 2024
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From: Richmond, Virginia
Burn in interrupted
So I got my 268H CAM in my 1980 L48. Bad valve adjustment, bad timing, other issues prevented me from starting for about 30+ cranks. Once I got her roughly timed correctly I got her started and she ran for about 15 minutes between 2000-2500rpm, smokey as hell. The valve noise was so bad (overloaded carb too) that I had to shut her down worrying that I was doing damage.
Now she is timed right and the valves are adjusted correctly (thanks @stingr69 ). Now I can start her easy.
QUESTION: Should I continue to break her in at 2000-2500 for another 15 minutes and shut her down and change the break in oil. Do I break her in for the full 25 minutes as if the first 15 minutes weren't even there? Or am I screwed entirely?
Thanks in advance.
Now she is timed right and the valves are adjusted correctly (thanks @stingr69 ). Now I can start her easy.
QUESTION: Should I continue to break her in at 2000-2500 for another 15 minutes and shut her down and change the break in oil. Do I break her in for the full 25 minutes as if the first 15 minutes weren't even there? Or am I screwed entirely?
Thanks in advance.
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The factory never did any of that back when it was new.
Set the timing, top up the coolant and go for a drive!
when I put in my Xtream energy cam. That's all I did.
15 thousand miles later, still purring.
Set the timing, top up the coolant and go for a drive!
when I put in my Xtream energy cam. That's all I did.
15 thousand miles later, still purring.
Le Mans Master
Joined: Mar 2004
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From: Little Rock AR
Glad I could help.
You can continue breaking in the cam for the total half hour. If something needs to be addressed, you can stop, fix it, then continue again.
Once that is done, you want to check ignition timing, carb settings, leaks etc. Make sure everything is right. If it all checks out, you go for a drive.
if you want to do an oil change, you can. I like to use an oil filter cutter and look inside to see if you got any metal in there. Just a check to make me feel better.
You can continue breaking in the cam for the total half hour. If something needs to be addressed, you can stop, fix it, then continue again.
Once that is done, you want to check ignition timing, carb settings, leaks etc. Make sure everything is right. If it all checks out, you go for a drive.
if you want to do an oil change, you can. I like to use an oil filter cutter and look inside to see if you got any metal in there. Just a check to make me feel better.
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Yes, that is fine. Comp cams even had a 3 seperate 10 minute break in periods. YOu would run for 10 mins, let the engine cool then do that again 2 more times. Ive done it both ways with no negative effects. I also do the breakin for the total 30 min time, then change the oil and drive it for 500 miles and change the oil again
Le Mans Master
Joined: Aug 2017
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From: Cool Northern Michigan
Uniquemicro,
There is not really a maximum time to break-in the cam. But there is certainly a minimum time.
You will not do any harm if you continue to break in for hours.
But wait! I know you don't want to hear this or do this but,
you really should remove one valve cover at a time. Using a white paint pen mark a line on the upper portion of the pushrod.
Just lay the V.C. back on the head and run the engine again. Remove V.C.
Note if ALL 8 pushrods are truly rotating. If so, the lifters are also, GOOD!
Now do the other side.
There is not really a maximum time to break-in the cam. But there is certainly a minimum time.
You will not do any harm if you continue to break in for hours.
But wait! I know you don't want to hear this or do this but,
you really should remove one valve cover at a time. Using a white paint pen mark a line on the upper portion of the pushrod.
Just lay the V.C. back on the head and run the engine again. Remove V.C.
Note if ALL 8 pushrods are truly rotating. If so, the lifters are also, GOOD!
Now do the other side.
