Snapped Pushrods....
#1
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Snapped Pushrods....
So I just finished my cam swap. I installed my TPiS ZZ409 Cam, Corvette LS7 lifters, Ford SVO 30# Injectors, and Trick Flow 7.300" Chrome Moly Pushrods. I swapped out the head gaskets, and cleaned everything up as well.
I got it all back together, and went to turn it over...didnt even crank...I figured it was just because I did all that crap and it hasnt run for 3 days so maybe it just need some help.
Cranked it again and it let out a LOUD backfire then turned over but no start...
I figured it just cleaned out excess fuel an gunk in the system...
Cranked it again and I heard a metallic snap and jingling...
Got out and looked. I had 1 Driver side and 2 pass side rockers loose...
Turned out 3 of the Chrome-moly Pushrods snapped.
I have Crane Cams 1.6 Gold Race Roller Rockers and AFR Heads 187cc
I think I had the stupid rockers too tight and they snapped the pushrods when it atarted to turn over. Lord knows how many I bent...
My question to you all is...
I know I have a task not to replace the broken/bent rods, but what else do I need to look at or what else probably broke with this???
I got it all back together, and went to turn it over...didnt even crank...I figured it was just because I did all that crap and it hasnt run for 3 days so maybe it just need some help.
Cranked it again and it let out a LOUD backfire then turned over but no start...
I figured it just cleaned out excess fuel an gunk in the system...
Cranked it again and I heard a metallic snap and jingling...
Got out and looked. I had 1 Driver side and 2 pass side rockers loose...
Turned out 3 of the Chrome-moly Pushrods snapped.
I have Crane Cams 1.6 Gold Race Roller Rockers and AFR Heads 187cc
I think I had the stupid rockers too tight and they snapped the pushrods when it atarted to turn over. Lord knows how many I bent...
My question to you all is...
I know I have a task not to replace the broken/bent rods, but what else do I need to look at or what else probably broke with this???
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Also how well will stock pushrods work with this setup??? I still have my stock 7.200" ones...Might throw them in and try that with some adjustment to my rockers
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I did, but that doesnt matter THAT much because I have adjustable Roller Rockers...even if they WERE slightly off, I can change the rockers to fit...I'm not worried about the CAUSE of the problem...I know what that was. I am going to replace my pushrods and loosen up the rockers before I try again...
I need to know what else I could have or definately did mess up when this happened!
I need to know what else I could have or definately did mess up when this happened!
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Isn't there some kind of warranty on the pushrods? You mite be able to get them replaced.
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I did, but that doesnt matter THAT much because I have adjustable Roller Rockers...even if they WERE slightly off, I can change the rockers to fit...I'm not worried about the CAUSE of the problem...I know what that was. I am going to replace my pushrods and loosen up the rockers before I try again...
I need to know what else I could have or definately did mess up when this happened!
I need to know what else I could have or definately did mess up when this happened!
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#8
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It sounds to me like you didn't do the right research on your build. You don't know if your rockers were self-aligning or non self-aligning? You didn't take any consideration into pushrod length? Big mistake.
Adjustable rockers give you the option to adjust valve lash, not pushrod length.
What did you tighten the rockers too? What lifter did you use? What method did you use to adjust them? Lots of questions to be answered.
Adjustable rockers give you the option to adjust valve lash, not pushrod length.
What did you tighten the rockers too? What lifter did you use? What method did you use to adjust them? Lots of questions to be answered.
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I took a quick look at Summit, it seems they make the Crane Golds in both SA and NSA, so you're going to have to check.
#12
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I'm going to say everything broke because he didn't adjust them properly using the correct method. If it's not spinning over something is obviously binding.
#14
Pushrod length ALWAYS matters. Adjusting rocker arm lash will do little to help improper valvetrain geometry due to the wrong length pushrods.
EDIT: You can roll the pushrods on a sheet of glass to see if they are still straight, but I would replace them all either way. No telling if any have been weakened while still maintaining their straightness.
EDIT: You can roll the pushrods on a sheet of glass to see if they are still straight, but I would replace them all either way. No telling if any have been weakened while still maintaining their straightness.
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I measured the length using a trick flow pushrod length checker. I ordered my 7.3 pushrods AFTER that. I did not buy the rockers myself, they were on the freaking car when I got it...THAT is why I dont know if they are SA or not!!! Stop taking so many damned stabs at me jesus.
I am new at this and I did my research. I know that LS7 lifters dont sit the same as stock LT1 lifters do. I know the lifters that were in the car before this upgrade were not stock but not LS7. They were measured to the cam because this cam has been in the car before. The rods were measured to fit that cam and lifter combo and they worked out to a 7.2" so he just used the stock 7.2" pushrods. When I switched to LS7's I saw that they had a slightly deeper cup depth so I measured. It came out to 7.3. So I ordered 7.3's!
The comment about the rockers was that if I was slightly off, like .100, I could make an adjustment with the rocker nut and compensate slightly if needed. I WAS NOT saying I could go out and buy 7.0 or 7.6 pushrods and "make them work" because my rockers are adjustable......
I went back to the stock 7.2" to see if that fixed it...shorter length. The rockers were FINGERTIGHT. I did not touch them with a ratchet at all. I never even GOT to adjust them, because the engine never started and I did not have the capability to hand crank the engine to set the lash and all, so I fingertightened them, bumped the engine, tightened any that were loose, bumped it, did the same...once they were fingertight I tried to start it...........bent 6 pushrods before it ever started.
I am new at this and I did my research. I know that LS7 lifters dont sit the same as stock LT1 lifters do. I know the lifters that were in the car before this upgrade were not stock but not LS7. They were measured to the cam because this cam has been in the car before. The rods were measured to fit that cam and lifter combo and they worked out to a 7.2" so he just used the stock 7.2" pushrods. When I switched to LS7's I saw that they had a slightly deeper cup depth so I measured. It came out to 7.3. So I ordered 7.3's!
The comment about the rockers was that if I was slightly off, like .100, I could make an adjustment with the rocker nut and compensate slightly if needed. I WAS NOT saying I could go out and buy 7.0 or 7.6 pushrods and "make them work" because my rockers are adjustable......
I went back to the stock 7.2" to see if that fixed it...shorter length. The rockers were FINGERTIGHT. I did not touch them with a ratchet at all. I never even GOT to adjust them, because the engine never started and I did not have the capability to hand crank the engine to set the lash and all, so I fingertightened them, bumped the engine, tightened any that were loose, bumped it, did the same...once they were fingertight I tried to start it...........bent 6 pushrods before it ever started.
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You need someone experianced to come help you in person. You made a huge mistake somehow. Admit it, find someone to help you identify what you have, what you damaged and what you need, and learn from this.
I thought LS7 lifters usually required a shorter pushrod not a longer one?? The heads could have had longer valves meaning they would need taller pushrods but I would have expected that to be offset by the LS7 lifters needing shorter.
I would say best case scenario would be severe bind with SA rockers and guideplates but doubt you will be that lucky doubt it would bend then I think it would just wear them. I would be pulling heads, I just think with that much pushrod damage you had to have hit the pistons.
I thought LS7 lifters usually required a shorter pushrod not a longer one?? The heads could have had longer valves meaning they would need taller pushrods but I would have expected that to be offset by the LS7 lifters needing shorter.
I would say best case scenario would be severe bind with SA rockers and guideplates but doubt you will be that lucky doubt it would bend then I think it would just wear them. I would be pulling heads, I just think with that much pushrod damage you had to have hit the pistons.
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I know I messed up, dont get me wrong...but I think I know what I did and it was not pushrod length...
I think I fucked up installing the cam. I think its at the wrong degree
I also think in the process I bent at leas t 2, maybe 3 valves...at least
I think I fucked up installing the cam. I think its at the wrong degree
I also think in the process I bent at leas t 2, maybe 3 valves...at least
#18
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I went back to the stock 7.2" to see if that fixed it...shorter length. The rockers were FINGERTIGHT. I did not touch them with a ratchet at all. I never even GOT to adjust them, because the engine never started and I did not have the capability to hand crank the engine to set the lash and all, so I fingertightened them, bumped the engine, tightened any that were loose, bumped it, did the same...once they were fingertight I tried to start it...........bent 6 pushrods before it ever started.
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Well...since I am about to buy new valves, I already have titanium retainers, upgraded springs, upgraded guideplates, etc...how likely is it to port the heads slightly and add in larger valves?