Harland Sharp Roller rockers backed off?
#1
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Harland Sharp Roller rockers backed off?
I built this motor about 3000k miles ago, I used red loctite when I installed them and torqued them to 22Ft-lbs. It sounds like it's constantly getting looser and I need to re-torque them again, it's only been about 100 miles since the last time I torqued them.
I'm going to pull them this weekend, clean out/chase the threads to get all of the old loctite out and re-loctite them in. Is there something I'm missing here? I bought them second hand, but they've been fine for 3000 miles until now.
Specs on the motor is just a stock rebuilt short block with PRC 2.5 5.3 heads, 233/239 cam, 7.400 Pushrods, PRC double valve springs. Brand new LS7 lifters.
I'm going to pull them this weekend, clean out/chase the threads to get all of the old loctite out and re-loctite them in. Is there something I'm missing here? I bought them second hand, but they've been fine for 3000 miles until now.
Specs on the motor is just a stock rebuilt short block with PRC 2.5 5.3 heads, 233/239 cam, 7.400 Pushrods, PRC double valve springs. Brand new LS7 lifters.
#3
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Do you know for a fact they are backing out?
Has your torque wrench been calibrated?
Did you clean the threads prior to using loctite (no oil)?
Do not use a tap in the threads, use a thread chaser. The tap will alter the thread class of fit by removing more material from the tapped hole in the head.
Has your torque wrench been calibrated?
Did you clean the threads prior to using loctite (no oil)?
Do not use a tap in the threads, use a thread chaser. The tap will alter the thread class of fit by removing more material from the tapped hole in the head.
#4
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Do you know for a fact they are backing out?
Has your torque wrench been calibrated?
Did you clean the threads prior to using loctite (no oil)?
Do not use a tap in the threads, use a thread chaser. The tap will alter the thread class of fit by removing more material from the tapped hole in the head.
Has your torque wrench been calibrated?
Did you clean the threads prior to using loctite (no oil)?
Do not use a tap in the threads, use a thread chaser. The tap will alter the thread class of fit by removing more material from the tapped hole in the head.
Threads were clean.
I'm leaning more towards this being a pushrod length issue as the rockers are noisy in general. I was actually consdering using brake cleaner to clean out the threads. I upgraded my cam/changed heads when I re-built the motor. For whatever reason I ended up re-using the 7.400 TSP pushrods I had from my previous cam kit from TSP.
I ordered a tool this evening, I'll check 'em and order the new ones probably next week.
#6
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In my opinion, you wasted your money and gave yourself something else to worry about. I have seen engines make 1000hp on the dyno with GM factory rockers with no problems. I have also had a car's engine completely destroyed while I was running it on the dyno due to an aftermarket rocker backing out. This caused a valve to collide hard with the piston...next thing you know, I am mopping up coolant and oil from the shop.
I classify most LS aftermarker rockers as "snake oil". They aren't going to do anything positive for you, and chances are they will upset your stomach.
I classify most LS aftermarker rockers as "snake oil". They aren't going to do anything positive for you, and chances are they will upset your stomach.
#7
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In my opinion, you wasted your money and gave yourself something else to worry about. I have seen engines make 1000hp on the dyno with GM factory rockers with no problems. I have also had a car's engine completely destroyed while I was running it on the dyno due to an aftermarket rocker backing out. This caused a valve to collide hard with the piston...next thing you know, I am mopping up coolant and oil from the shop.
I classify most LS aftermarker rockers as "snake oil". They aren't going to do anything positive for you, and chances are they will upset your stomach.
I classify most LS aftermarker rockers as "snake oil". They aren't going to do anything positive for you, and chances are they will upset your stomach.
Once I get the proper length push rods and put them back down to torque with some fresh red loctite I don't think I'll be worrying about it anymore.
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#8
TECH Senior Member
Get yourself a p-rod guage and check your pushrod length. It is possible also the threads in your head bolt hole going bad, not allowing the bolt to "grip". Double check things carefully, inspect the bolt holes for unnusual wear.
#13
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Harland Sharp = Fail. I have seen them cause more catastrophic failures in LS engines than any other rockers combined. I have a set of low mile (32K) stock rockers from an engine swap that I just did if you want them pm me Ill sell them to you cheap just to stop your head aches.