I have a loud tapping that is definetly valve train related that only appears after a WOT sprint.
I have hardened 7.42'' pushrods and new, OEM comp lifters to go along with my Comp cam (214*-.601'').
What could be the culprit? To me it almost sounds like I may have sort of oil starvation problem? Why would it only tick after WOT? Oil pressure is 40-60 at all times.
Any guesses or help would be appreciated...
__________________ 2007 Chevrolet Colorado Crew Cab
3.7L I5, 4L60E
Alpine speakers/Kicker amp/Boston G8 subs
HP Tuners - self tuned
Generally speaking, the oil would be up top after a blast, not in the pan, so oil starvation I wouldn't think would do it. Does it get quieter after you do it and let it cool down (while running) or does it stay the same until you shut it off, cool, then try again?
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Generally speaking, the oil would be up top after a blast, not in the pan, so oil starvation I wouldn't think would do it. Does it get quieter after you do it and let it cool down (while running) or does it stay the same until you shut it off, cool, then try again?
I wouldnt necessarily say 'every' time but for the most part yes, I have to cut it off, let it cool, and then recrank for the tapping to go away.
So therefore, we are looking at a valve train part... Somethings changing after WOT to...... idk, I'm stuck.
__________________ 2007 Chevrolet Colorado Crew Cab
3.7L I5, 4L60E
Alpine speakers/Kicker amp/Boston G8 subs
HP Tuners - self tuned
sounds like a problem I had awhile back, it was a lifter collapsing under high RPM, then when it did, the rocker would clatter. If I shut it off for a bit it would be fine
__________________ Dad--
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sounds like a problem I had awhile back, it was a lifter collapsing under high RPM, then when it did, the rocker would clatter. If I shut it off for a bit it would be fine
Should I swap in Morels? Or... What exactly did you do to fix your problem?
__________________ 2007 Chevrolet Colorado Crew Cab
3.7L I5, 4L60E
Alpine speakers/Kicker amp/Boston G8 subs
HP Tuners - self tuned
What valvesprings are you using?Take a look at your pushrods.
I was using 918s with stock pushrods. Then, I swapped in 7.4'' hardened pushrods. I even went to a 7.5'' pushrod thinking my preload was completely off. Motor wouldn't even crank. Now, I'm using a 7.425'' pushrod.
This is with the 214-.601'' cam (1.43 base circle), .043'' head gasket, and .030'' mill.
I've been under the assumption that it was pushrod related the entire time. Now, I'm starting to believe it has nothing to do with push rod length and preload has been correct from the get go. I even used a pushrod length checker but was led to believe, it had to be wrong seeing as it was still tapping.
__________________ 2007 Chevrolet Colorado Crew Cab
3.7L I5, 4L60E
Alpine speakers/Kicker amp/Boston G8 subs
HP Tuners - self tuned
When you say wot, you mean a wot run up to what RPM for how long?
When did this start?
I took it from 2800-6000 + (1st gear) yesterday, and it started it's routine of the loud taps.
It started after the cam swap. So we replaced the heads, swapped in new lifters and pushrods. Still, the same noise is there. These are Comp OEM, replacement lifters by the way.
__________________ 2007 Chevrolet Colorado Crew Cab
3.7L I5, 4L60E
Alpine speakers/Kicker amp/Boston G8 subs
HP Tuners - self tuned
Let me ask you this. When you did your camswap, did you pull your oil pump off? What im getting at is i FUBARd my o-ring during mine but still had pressure. I hopped on it and saw a large amount of tapping afterward. Just a thought and if so, thats an easy fix.
Stock pushrod length is like 7.398 or so The Comp lifters are probably a couple thousandths taller than the stockers. 1.551" is the stock base circle and your runnin a 1.430" basecircle cam so that would require a .060" longer pushrod to take up the slack but you milled the heads .030" so a .030" longer pushrod is whats required...on paper, which is about what youve got now. I think when you had the 7.400"s in it and swapped to 7.500"s you may have damaged one of the lifters, was the noise there when you was runnin the 918s and stock pushrods?
Let me ask you this. When you did your camswap, did you pull your oil pump off? What im getting at is i FUBARd my o-ring during mine but still had pressure. I hopped on it and saw a large amount of tapping afterward. Just a thought and if so, thats an easy fix.
I should note that the tapping fluctuates with RPM. Would a damaged o-ring have any correlation?
Quote:
Originally Posted by Bo White
Stock pushrod length is like 7.398 or so The Comp lifters are probably a couple thousandths taller than the stockers. 1.551" is the stock base circle and your runnin a 1.430" basecircle cam so that would require a .060" longer pushrod to take up the slack but you milled the heads .030" so a .030" longer pushrod is whats required...on paper, which is about what youve got now. I think when you had the 7.400"s in it and swapped to 7.500"s you may have damaged one of the lifters, was the noise there when you was runnin the 918s and stock pushrods?
Possibly but, the problem has been around since the cam swap and at that time I was using stock pushrods.
Quote:
Originally Posted by DaddySS
Let's see, it was there right after the cam swap, you then put in new heads, lifters, pushrods and it is still there - correct?
For the original cam work, what was done - just a cam? Did you do oil pump? What are the full specs of the cam? Are you still using the 918 springs?
It sounds like you have either an oil starvation problem at higher rpm, or something is forcing one of the lifters to collapse a bit.
How is the P/V clearance?
What oil are you using, what oil filter?
Here's how it went. About three months ago, I swapped in a 214/212 .601''/571'' 108LSA cam, 918 springs, and a new timing chain. Everything else was left stock. There was a slight ticking that was audible, and this soon became a loud tap after WOT and a few times, just plain randomly.
Then I decided to swap in new pushrods (7.4''), Comp OEM lifters, and 5.3L heads that had been milled .030''. As soon as I cranked it up, the barely audible ticking was still lingering around. Going WOT would almost guarantee the loud tapping that does not go away until you let the motor cool down.
I'm not positive on P2V, however the stock 5.3L pistons are dished and I'm at a 108 ICL with this cam. (Very common setup)
Lastly, I've been using FRAM filter and Penzoil 10-30 oil.
__________________ 2007 Chevrolet Colorado Crew Cab
3.7L I5, 4L60E
Alpine speakers/Kicker amp/Boston G8 subs
HP Tuners - self tuned
Im runnin a "Flam" filter, never had a problem with any of the hundreds Ive ran on the 11 Camaros, 3 Mustangs, 2 S10s, 3 Explorers(that were mail delivery vehicles with 600+ stops a day), a F150, a Beretta, and a Grand Marquis that my family has had. I will say(and admit) that some filters are better than others but as long as your runnin a filter its all good.
I should note that the tapping fluctuates with RPM. Would a damaged o-ring have any correlation?
Possibly but, the problem has been around since the cam swap and at that time I was using stock pushrods.
Here's how it went. About three months ago, I swapped in a 214/212 .601''/571'' 108LSA cam, 918 springs, and a new timing chain. Everything else was left stock. There was a slight ticking that was audible, and this soon became a loud tap after WOT and a few times, just plain randomly.
Then I decided to swap in new pushrods (7.4''), Comp OEM lifters, and 5.3L heads that had been milled .030''. As soon as I cranked it up, the barely audible ticking was still lingering around. Going WOT would almost guarantee the loud tapping that does not go away until you let the motor cool down.
I'm not positive on P2V, however the stock 5.3L pistons are dished and I'm at a 108 ICL with this cam. (Very common setup)
Lastly, I've been using FRAM filter and Penzoil 10-30 oil.
So if you let it get completely warm but don't run it up in the RPM range it remains quiet?
Check the oil ump o-ring I told Beau and he didnt believe me that, that was his problem but he pulled it and there it was, a crimped o-ring. It is VERY easy to screw up the ring. Hell I even did it when I installed the pick up tube while the motor was on an ENGINE STAND I have the same issue in my 418 with what you are talking about, cold it doesnt tap at all but once the oil gets hot(thin) it starts tapping, and a WOT run makes it sound like its about to fall apart. If its not teh o-ring on the pump then you got me stumped. If it is a chewed o-ring then make sure when you put the new one to put a bunch of oil on it and the intake of the pump so it slides in nice and easy.
Loud Tapping, only after WOT 
I told Beau and he didnt believe me that, that was his problem but he pulled it and there it was, a crimped o-ring. It is VERY easy to screw up the ring. Hell I even did it when I installed the pick up tube while the motor was on an ENGINE STAND
I have the same issue in my 418 with what you are talking about, cold it doesnt tap at all but once the oil gets hot(thin) it starts tapping, and a WOT run makes it sound like its about to fall apart. If its not teh o-ring on the pump then you got me stumped. If it is a chewed o-ring then make sure when you put the new one to put a bunch of oil on it and the intake of the pump so it slides in nice and easy.
