southernspeed said:
cant tell you how many times I did that CK5
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new cam, backfires thru intake
- Thread starter 89Burben
- Start date
cant tell you how many times I did that 
mouse
1/2 ton status
Some more to think about. With valve noise happening, more than likely the knock sensor is picking this up and retarding the timing when this occurs. It could go as far as contributing to the back fire issue.
I would eliminate any ticking first, then go from there.
I would eliminate any ticking first, then go from there.
i poped off the valve cover off of the passenger side and saw one of the intake rockers wasnt lifting as much as the others. proceded to take the rocker off and pushrod, took a long magnet to get the lifter out and i can only pull it out about 3/8 of an inch. this leads me to believe that the cam lobe is wiped and mushroomed my lifter..........this sucks. Especially when i called comp cams to specifically ask them what oil to use and whatnot....and the guy stated "Yea weve been having lots of trouble with ppl breaking in their cams and wiping the lobes."
That sucks dude.. I had a suspicion it might be that.. I'd be curious to see a pic of the cam once out... I've always been a devout Comp Cams fan and have never had a prob.. Best of luck with it and keep us updated...
Once a cam lobe has the surface hardening shredded off of it, then the cam lobe goes flat real quick. I do not think the problem was with the cam or the assembally lube you used. More people have shredded new camshafts, when following repair manual instructions and valve lash specifications, than I can count.
Russ
1/2 ton status
I know exactly what you are going through, I recently wiped out #2 exhaust lobe on the first comp cam I put in my big block during break-in. It was the computer friendly comp cam and adjusted exactly to their directions that came with the cam. I even used that aftermarket spray oiler system for the cam to try and prevent a failure. They sent me another cam replacement which is one of their extreme energy line. This one broke in fine but is a noisy cam after it is warmed up. I get a lot of valvetrain noise, sounds just like lifters tapping. I have adjusted them numerous times and finally after a long discussion with a rep at comp cams they told me the extreme energy line is a very noisy cam in a big block and they get a lot of complaints from folks about them. They attributed it to the ramp angle which causes the valve to close fast and make noise. I don't know how much of that I believe, but I am about fed up with the noise and it looks like I am going to tear into the engine for a third time and replace it with a roller cam this time like I should have done in the first place.
Russ
Russ
78Suburban
1/2 ton status
ryoken said:
x2
is a roller cam worth the money? i was reading about them....it basically eliminates the headaches with break in...but you need shorter pushrods, a cam button and wear plate....anyone have luck with retro fitting a roller cam?
i tried to upload pics but i cant.....
one thing that bothers me......
are the lifters supposed to be centered over the lobes on just a regular hydrualic flat tapped cam??
i have read that the lifters have a slight concave machined into them so they will center the cam? is this correct? or does the placement of the timing gear on the crankshaft center the cam on the lobes........on mine i just bottomed the gear till it couldnt go any more......
one thing that bothers me......
are the lifters supposed to be centered over the lobes on just a regular hydrualic flat tapped cam??
i have read that the lifters have a slight concave machined into them so they will center the cam? is this correct? or does the placement of the timing gear on the crankshaft center the cam on the lobes........on mine i just bottomed the gear till it couldnt go any more......
Actually they are concaved so they will spin 360 degrees on the cam lobe. It is bad for a lifter to sit in one spot because it will start to wear out if it does.
Do not worry about centering the camshaft. This is not a major mistake made on a regular basis by people when installing a new cam.
R77K10
Banned
you put any EOS in it ?
on the rocker adjustment deal, it is and always has bene zero lash plus one full turn adjustment
this centers the plunger in the body of the lifter- of its travel inside there
no matter what anyone or anything states
good luck
on the rocker adjustment deal, it is and always has bene zero lash plus one full turn adjustment
this centers the plunger in the body of the lifter- of its travel inside there
no matter what anyone or anything states
good luck
Russ
1/2 ton status
The lifters will not sit on the center of the lobe, they will sit a little forward of it. The cam has a small bevel ground into it to make the lifter spin on the lobe as the cam turns.
Russ
Russ
I'm sure when I did my last TBI motor build, the cam timing marks were both at 12o/clock, not 6 and 12 like yours. Maybe someone else can comment on this.
I seem to remember setting them up as you have but noticing it was wrong while I was rotating the engine to do the valve lash.
Just a thought about your spitting back problem although I'm not even sure it would run 180* out.
I seem to remember setting them up as you have but noticing it was wrong while I was rotating the engine to do the valve lash.
Just a thought about your spitting back problem although I'm not even sure it would run 180* out.
Russ
1/2 ton status
That is the same way mine sit on the cam. As far as I know that is the correct placement. I know what you are going through, your lifters look exactly like mine did on the TBI Cam after break-in. Just out of curiosity, which lobe was it that flattened?
Russ
Russ
Russ
1/2 ton status
Mine was #2 exhaust. My engine still seems to make more valvetrain noise out of the front passenger side than it does on the drivers side, even with the replacement cam. I was running the cam oiler and was concerned that it was robbing too much oil from the lifters in that corner since that is where it taps into the block so I took it off, but it did not seem to make any difference with the noise. That is mainly why I am considering swapping to a roller cam.
Russ
Russ
mouse
1/2 ton status
I guess that I can join the club today. Last week I noticed some rocker noise (that gave the knock sensor fits), so I tried to adjust it. It would go in and out, noisy, quiet. Just #2 intake. I pulled the intake to see whats going on...lifter is almost like the one above. I'll call Comp cams tomorrow for a stock computer friendly replacement.
