Wiped old cam NEED HELP
#1
Junior Member
SHOW GUEST
Thread Starter
Join Date: Mar 2007
Posts: 5
Wiped old cam NEED HELP
I have a 468 Chevy motor in my 67 Chevelle. This winter I took the motor out of the car to fix an oil pan gasket leak. While I had the pan off, I checked the main bearings and decided to replace them. I also replaced the rod bearings. The camshaft and the lifters were replaced less then 4000 miles ago. I miked the lobes of the cam and they were all within a couple of thousand of each other. I reused this cam and the lifters.
I tested the old valve springs and found that they had 70 pounds when closed. The cam requires 144 pounds when closed. I replaced the springs with a set of Comp cams beehive springs, 26120-16 The cam was a Crane cam 134781. solid lift .567 intake .590 exhaust 314 duration.
Since the was a used cam, I did not think to use a break in start up. I did coat the cam and lifters with Lucas Oil stabilizer. I did prime the motor and used Valvoline 10w30 nsl oil in the motor.
In less then 200 miles, I started to wipe a lobe off the cam.
Did the new, heavy, spring pressure without moly lube and a proper start up kill this cam? Should I pull the motor out and do a total dissemble and clean the insides?
Or can I replace the cam and lifters, change the oil and filter and hope for the best?
Thank You
Tony
I tested the old valve springs and found that they had 70 pounds when closed. The cam requires 144 pounds when closed. I replaced the springs with a set of Comp cams beehive springs, 26120-16 The cam was a Crane cam 134781. solid lift .567 intake .590 exhaust 314 duration.
Since the was a used cam, I did not think to use a break in start up. I did coat the cam and lifters with Lucas Oil stabilizer. I did prime the motor and used Valvoline 10w30 nsl oil in the motor.
In less then 200 miles, I started to wipe a lobe off the cam.
Did the new, heavy, spring pressure without moly lube and a proper start up kill this cam? Should I pull the motor out and do a total dissemble and clean the insides?
Or can I replace the cam and lifters, change the oil and filter and hope for the best?
Thank You
Tony
#2
Senior Member
RACING JUNKIE
Join Date: Jan 2006
Location: La.
Posts: 2,890
I've seen this happen if you did not put the same lifter on the same lobe that it was removed from (this has happened to me). Each lifter and lobe wears differently while in use. Normally it's best to install new lifters, or to grind and lap the old lifters before re-installing them. I realize that not everyone has access to a surface grinder, so it's best to spend the bucks on new lifters in most cases.
JMO
Zip.
JMO
Zip.