rocker pedastals & shafts

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Seight-V8
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rocker pedastals & shafts

Post by Seight-V8 »

hiya all,

Is it usual for the rocker shafts to bend during use???

I know mine where knackered but..didnt expect them to be bent upto about 3mm over the length.

Also the rocker pedastals are no longer round where the shaft goes...i recon about 0.50mm out of round.

anyone have exprience of this.

Shall i use the pedastals or gets some new ones.

cheers

scott


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Post by katanaman »

At a guess I would say something bad has happened in the past. The shafts can flex slightly but personally I have never seen them bend without a major incident. I would get new pedestals as well or at least good second hand ones. Your in an area of the engine where a slight change in size can make a fair difference because of the lever action
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Post by kiwicar »

They sound knackered to me 8) :? :lol:
I would look at the threads in the heads where the pedistals bolted down. To do all that to the shafts must have put some loads into the head castings. That is if someone didn't just put them on the floor and trod on them during a previous rebuild.
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Post by ppyvabw »

Also, someone has possibly used shims in the past and used different ones on different pedestals maybe?

Before reassembling make sure the platforms on the heads are all the same height (and the pedestals for that matter)
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Post by sidecar »

The pedestals going slightly oval is due to the bolts pushing the top of the pedestal down on the shaft. IMHO they will still be OK to use. Some bright spark mentioned this before and said the you can warm them up to get them to slide over the new shaft a bit easier, which is a good idea.
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Post by katanaman »

Sorry I was thinking the pedestals were oval the other way, my bad.
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Seight-V8
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Post by Seight-V8 »

hiya all,

So anyone doing replacement pillars...maybe in steel or billet.

That aint gonna break the bank so to speak.

Was thinking some outrigger posts may also be a good idea.

cheers

scott
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