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Discussion Starter #1
I put a Herbert Performance Camshaft in my BBC and during the break-in at 2500 RPM for 20 minutes the engine ran perfect, but recently it began to run rough, popping noises out the exhaust and a clanking noise coming from inside the engine, my neighbors thought it was a bent push rod, I suspected a cam failure and pulled the intake and found #6 and #8 exhaust lifters and they are completely trashed, wavy faced and wiped out at a angle. Im so pissed off right now. :mad:
 

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Been there, done that. Do you have dual valve springs? Did you take the inner springs out for break in? Did you use Break-In Oil Additive? I've seen more than a few motors trashed because of cam failure during break-in. Very, very frustrating. I hope you didn't trash your bottom end with all the shavings. Better pull it out and check. Personally I would tear it completely down and have the oil galleries cleaned out at a machine shop. Better safe than sorry.
 

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Just went through this myself a month ago. I had the same symptoms and it was driving me nuts. Finally pulled driver side valve cover when it was running and 3 rockers wern't moving at all. When I pulled the lifters there were deep groves in the face of them and it also sent shavings all though my motor and even destroyed my oil pump so badly it couldnt be turned by hand. Had to have my $700 Eagle crank turned .020 on the mains and .010 on the rods. Definatly pull the motor and have it hot tanked and new cam bearings installed. It not worth the risk hoping metal didnt hurt anything else and throwing it back together. Use lots of assembly lube on the cam and lifters and use the break in oil addative. Set your timing so it will fire the instant you turn it over. You don't want to be cranking it over and over trying to get it to run and wiping all the lube off.
 

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Discussion Starter #4
I did all that stuff, I have broken-in several cams and this is the first one I had do this. I think it was a cheap lifter problem. I used Moly Lube on the cam and oil on the lifters, with Valvoline VR1 oil.
 

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Did you lift the rocker covers to see if the push rods were spinning? You can save an engine if you spot non-spinning lifters and replace them before there is damage.
I always put a paint pen dot on each push rod to make it easier to see them turning.
 

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My engine builder used Joe Gibbs break in oil, I ran the engine for 30 min @ 2000 RPM, road tested it and then changed the oil to 15W40 Rottella T and didn't fire the car up until it completely cooled down. So far so good.
 

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I always put a paint pen dot on each push rod to make it easier to see them turning.
Ok, nuther idea I like. Keep giving yer secrets!! Umm, these tips from the guys that know dont usually come free... Take it all in guys... JR
 

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learn to

love this stuff , cuz it loves your parts


http://www.jegs.com/i/Pro+Blend/797/6080/10002/-1

i used to be a distributor for this stuff ,, i've tested moly type assembly lubes , they're not even close to this stuff

How much pre-load did you have in the adjustment ?? Its another reason i like a hydraulic at .000 or .002with no preload. Whatever you put on the cam will be wiped off with alot of preload.

How much did you have to crank the engine before it fired and started ??
 

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I think Paul is on to it.... non easy spinning lifter have lead to more failures than any combination of other factors combined.....

particularly in BBC with its odd lifter angle

Nothing wrong with your procedure, oils or assembly lube....
 

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Discussion Starter #10
I just called Doug Herbert Performance and the Tech man told me I have something wrong with my engine or it was something I did. I told him I followed the directions exactly. He asked what oil I was running and I told him I use Valvoline VR1 and he laughed and said that oil wont work for a flat tappet ! :mad: Im so pissed at their customer service! BTW, he told me Crane and Comp makes their cams for them.
 

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Did you know Flat tappet lifters aren't flat on the bottom? They are very slightly spherical. The cam lobe is not flat either, it's tapered to one side or the other.
Adjacent lobes are tapered opposite and this keeps the cam in place fore and aft. When the cam turns this taper spins the lifter. If your lifters don't spin they will wear out the lobes. Stop the engine and replace a non spinning lifter before damage occurs.

If you didn't check for spin then it's all speculation what caused it.

Another common problem is excessive cranking trying to get an improperly set distributor to fire at the right time. The lube on the lobes won't last forever. Have the engine ready to fire before cranking. If built and set up right it will fire right up.
 

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Discussion Starter #12
It did fire up right away, I know what I'm doing. I'm a ASE Master tech and I know this was a problem with the lifters. And this isn't the first cam I have broken-in, but it's the first I had fail!
 

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Is it a high lift cam?
 

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.575 Intake .577 exhaust
That's what mine is .575 and .575, the only thing I was told was to remove the inner spring, but my engine builder left it all together and gave me the run down on the new oils. I had my engine fired up and right to 2000 rpm. I recently sheared a lifter in half on initial fire up, even Comp Cams wasn't sure why. It's not hard to wipe them out if they get starved for oil or wont spin, because it's all splashed up to the cam and the BB angled set up doesn't help.

Sorry about your cam!
 

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I run a solid aluminum cam button on most of the flat tappet small blocks I've assembled, don't know if they've benifited from it but I know it didn't hurt. I haven't had any cam/lifter failures.
 

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I run a solid aluminum cam button on most of the flat tappet small blocks I've assembled, don't know if they've benifited from it but I know it didn't hurt. I haven't had any cam/lifter failures.
it wont benefit froma a cam button because flat tappet cams have a taper ground into to them so that the lifter will spin and that taper also forces the cam to push towards the back of the block.....
 

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came in a Lunati box with a Lunati cam card ,, sometimes i wonder if even a solid or hydraulic could benefit from a cam button like a roller needs.
I am running a button in mine and I am running a solid. Less wear on the cam/oil pump/distributor drive gear.
 

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dont know what the guy at herbert was smokingb ut it was good stuff for sure:yes:

ive been running vr1 thru this motor its entire life all be it about 100 miles but its a drag racing only motor with a solid cam. the vr1 has a good amount of zinc in it it is great for a flat tappet cam. its got more zinc then gtx 20-50 by a good ways.

i use VR1 straight 50:yes:
 
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