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Re: Opinions on rocker arm failure.
[Re: Azzkikrcuda]
#1454033
06/17/13 10:16 AM
06/17/13 10:16 AM
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Joined: Nov 2009
Posts: 2,177
ill
dennismopar73
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Quote:
Had a rocker arm failure last weekend, center three rockers on right side. Looks like they started to seize to the shaft and heated up and stretched and broke. All other rockers on that side and other side are ok. Checked cam lobes (solid cam), valves, coil bind and retainer clearance. Engine has good oil pressure and has oil to rockers on both sides when turning oil pump with drill. These are the older hughes/dove rockers. This engine has been together and running great for a few years. Not sure what caused the failure. Any ideas?
Well the lack of oiling is the root cause!
Whether it is from the shafts on upside down, or cam bearing turned has to be determaned !
It is hard to believe that a street car, that the squelling grinding noises this type of damage that is seen, was not heard ! not to mention the clattering of lifters early on!
If what you say is true about the oiling on that side is still there, then those rocker shafts was installed upside down!! 
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Re: Opinions on rocker arm failure.
[Re: moparlifer]
#1454036
06/17/13 02:10 PM
06/17/13 02:10 PM
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Joined: Sep 2004
Posts: 2,093
oberlin, Ohio
Rapid340
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oberlin, Ohio
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I have used Dove rockers without isssue, the aluminum alloy they use (7129) is stronger than what most manufacturers use.
I dont think the shafts were upside down(I bet the scuffing is not as severe on the opposing side of the shaft - cant see in pic) and if there were burrs left on the banana grooves, problems with changing valve lash ect would have been noticed soon after initial use.
I blame oil starvation. It does look as though the banana groove extends beyond the wear/scuff marks in several rocker locations that can be seen (not good) and I would be looking at this closely.
1971 Factory Appearing Duster 340 11.000 @ 122 mph
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Re: Opinions on rocker arm failure.
[Re: Rapid340]
#1454038
06/17/13 03:44 PM
06/17/13 03:44 PM
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Joined: Jan 2003
Posts: 1,811
North Dakota
Azzkikrcuda
OP
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OP
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North Dakota
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The cam bearing is not turned, as it shoots a nice stream of oil out the feed hole in the head when you turn the oil pump over with a drill. The shaft was installed correctly. The grooves do extend beyond the bodies on most of the rockers.
The only Carbs I care about are under the hood!
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Re: Opinions on rocker arm failure.
[Re: Azzkikrcuda]
#1454039
06/17/13 04:13 PM
06/17/13 04:13 PM
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Joined: Aug 2011
Posts: 2,872
Pattison Texas
CSK
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master
Joined: Aug 2011
Posts: 2,872
Pattison Texas
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did the end plugs on the shaft fall out ??
1968 Charger COLD A/C Hilborn EFI
512ci 9.7 compression, Stealth heads, 4.10 gear A518 ODtrans 4100lb,10.93 full street car trim
2020 T/A 392 Stock 11.79 @ 114.5
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Re: Opinions on rocker arm failure.
[Re: JohnRR]
#1454041
06/17/13 04:32 PM
06/17/13 04:32 PM
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Joined: Dec 2006
Posts: 3,397
Pa
Hot 340
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master
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Pa
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Quote:
Quote:
The grooves do extend beyond the bodies on most of the rockers.
That's a problem .
unless he uses hold-down blocks that the shafts fit through, and clearances were somewhat snug between each rocker set..
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Re: Opinions on rocker arm failure.
[Re: Hot 340]
#1454042
06/17/13 04:47 PM
06/17/13 04:47 PM
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Joined: Jan 2003
Posts: 75,095
A Banana Republic near you.
JohnRR
I Win
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I Win
Joined: Jan 2003
Posts: 75,095
A Banana Republic near you.
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Quote:
Quote:
Quote:
The grooves do extend beyond the bodies on most of the rockers.
That's a problem .
unless he uses hold-down blocks that the shafts fit through, and clearances were somewhat snug between each rocker set..
That is true , if he set it up it's .015ish clearance , but still that's enough to bleed off more oil there than if there were no grooves.
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Re: Opinions on rocker arm failure.
[Re: JohnRR]
#1454043
06/17/13 06:21 PM
06/17/13 06:21 PM
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Joined: Apr 2006
Posts: 3,675
Akron, Ohio U.S.A.
roadhazard
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master
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Akron, Ohio U.S.A.
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Man I have never seen rockers that jacked up before  Possible over torque on the shafts causing less clearance between the rocker and shaft in certain areas  Measure and see how round the shafts are at the mounting points. I just can't get over those rockers 
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Re: Opinions on rocker arm failure.
[Re: Azzkikrcuda]
#1454044
06/17/13 06:21 PM
06/17/13 06:21 PM
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Joined: Nov 2009
Posts: 2,177
ill
dennismopar73
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Quote:
The cam bearing is not turned, as it shoots a nice stream of oil out the feed hole in the head when you turn the oil pump over with a drill. The shaft was installed correctly. The grooves do extend beyond the bodies on most of the rockers.
I will stick to my original statement!
This type of damage only occures thru the lack of oiling issues!
Either blockage, or incorrect install!
and the amount of the damage that the issue had been ran awhile!
Be that as it may the motor has to be torn down and completely gone through everything replaced!
pay close attention to cam bearing install, and cleaning of oil passages!
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Re: Opinions on rocker arm failure.
[Re: dennismopar73]
#1454045
06/17/13 07:02 PM
06/17/13 07:02 PM
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Joined: Nov 2004
Posts: 3,168
Wichita Kansas
B Dartman
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master
Joined: Nov 2004
Posts: 3,168
Wichita Kansas
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Quote:
I would be looking for all the aluminum,and where it went....pull the pan,if not engine to inspect,imho.
Agree. Unfortunately last summer I had a lifter on its way to failure (flat tappet with little to no load) and the bottom of the lifter became concave the associated cam lobe had begun to wear down too. Wear was minimal but took the approach mentioned above and ended up finding metallic residue from cam and lifter on the windage tray and scoring in the oil pump (that metal all has to go somewhere). Went ahead and turned a cam swap into an overhaul.
Hope you get it all sorted out and back in working order!
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Re: Opinions on rocker arm failure.
[Re: Azzkikrcuda]
#1454047
06/17/13 08:12 PM
06/17/13 08:12 PM
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Joined: Jan 2007
Posts: 685
pennsylvania
poboyengineering
mopar
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mopar
Joined: Jan 2007
Posts: 685
pennsylvania
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how are the pushrods?
looks like they cut the side of the rocker...
It may be ugly, but it sure is slow.
Girls comb their hair in rear view mirrors and the boys try to look so hard....
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Re: Opinions on rocker arm failure.
[Re: B Dartman]
#1454051
06/18/13 01:11 AM
06/18/13 01:11 AM
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Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
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Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
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Quote:
Quote:
I would be looking for all the aluminum,and where it went....pull the pan,if not engine to inspect,imho.
Agree. Unfortunately last summer I had a lifter on its way to failure (flat tappet with little to no load) and the bottom of the lifter became concave the associated cam lobe had begun to wear down too. Wear was minimal but took the approach mentioned above and ended up finding metallic residue from cam and lifter on the windage tray and scoring in the oil pump (that metal all has to go somewhere). Went ahead and turned a cam swap into an overhaul.
Hope you get it all sorted out and back in working order!
Hate to tell you but if you had metallic in the pan
doent mean you needed a total rebuild... if you wipe
out a cam the debris will fall to the pan... yes the
pump will be trashed but the filter picks up the crap
before it goes to the bearings... bearings are the
first thing in line after the filter
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Re: Opinions on rocker arm failure.
[Re: loaderpro]
#1454052
06/18/13 09:21 AM
06/18/13 09:21 AM
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Joined: Nov 2003
Posts: 5,048
Atlanta Indiana
Dave Watt
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master
Joined: Nov 2003
Posts: 5,048
Atlanta Indiana
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Quote:
I say oil starvation as well, no disrespect but you say the shafts were on correct...meaning the oil holes were pointing down AND towards the exhaust manifolds?
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