Rocker bearing failures
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Rocker bearing failures
Every year we have had to replace multiple rocker arm shaft bearings this year seems worse. Does anyone have much experience using a full compliment bearing over a caged bearing for same application? Seems like there would be more surface area both in number of needles and length of needles. Hence more load carrying capabilities. Circle track application. Maybe bushings but with no positive oiling I’m not going there. I don’t think lubrication is an issue it’s to random.
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Re: Rocker bearing failures
Enough oil or not, you can NOT get away from the SMALL contact area of the needle bearings, THAT is the Achilles heel of needle bearing roller lifters. Mark H.
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Re: Rocker bearing failures
Would be the same with rocker arms, made worse with higher rocker arm ratios.
Re: Rocker bearing failures
Alum or steel rockers? Steel rockers being stronger than alum don't need as much metal to wrap around the bearing to maintain equivalent strength. All the steel & s/s rockers I have seen use larger bearings for this reason, with resulting longer life.
Re: Rocker bearing failures
Valve float. How much base circle runout? Any lobes with more than others? What is the cam?
Re: Rocker bearing failures
Alum rockers. I doubt valve float I use soft lobes all ti valves. It could be the substrate we have less issues with steel rockers. I’ve spent a lot of time and finally found a bearing supplier that sells full compliment in the specs I need. Keep in mind every peer that I’ve contacted that uses this brand has this issue on occasion.
Re: Rocker bearing failures
What engine family and type? What max. rpms.? What valve lifts and rocker ratios? What style rocker arm? What racing use? What oil weights and pressures?
To much unknown here to even make a intelligent WAGMAR.
To much unknown here to even make a intelligent WAGMAR.
The Older I Get, The Dumber I Get
- midnightbluS10
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Re: Rocker bearing failures
MAR would be? Made at random?
JC -
bigjoe1 wrote:By the way, I had a long talk with Harold(Brookshire) last year at the PRI show. We met at the airport and he told me everything he knew about everything.It was a nice visit. JOE SHERMAN RACING
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Re: Rocker bearing failures
In my opinion ... not enough oil flow at that point for lubrication or cooling those needle bearings.
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Specialty engine building at its finest.
Specialty engine building at its finest.
Re: Rocker bearing failures
Do the rollers roll over the one in front and one behinds path by at least 50%?
- af2
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Re: Rocker bearing failures
I have a feeling what rockers are being used. After 2 sets the second was provided free of charge LOL! I went to a whole different set up and never been happier. 10 years and the the lash has never been more than .002 different.
GURU is only a name.
Adam
Adam
Re: Rocker bearing failures
410 sprints, rpm 8400 some as hi as 9000 on occasion, .440 lobe 1.70 or 1.75 ratio, no oil restrictors, 7/16 .165 pushrods,
I have so many customers on oil sponsorship that each uses a diff brand. When the cars are hooked up the low rpms for a lap will be 5800/6200 and the highs the aforementioned 8400 and up. Sometimes like holding it wot for 7 minutes.
I have so many customers on oil sponsorship that each uses a diff brand. When the cars are hooked up the low rpms for a lap will be 5800/6200 and the highs the aforementioned 8400 and up. Sometimes like holding it wot for 7 minutes.
Re: Rocker bearing failures
Are you using the Jesel Pro Steel series rockers and stands?
The Older I Get, The Dumber I Get