W/NG rocker box - clearence?

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christian.mutke
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W/NG rocker box - clearence?

Postby christian.mutke » Sun Nov 08, 2015 6:55 pm

Hi everybody!

At the first go-off of my engine I noticed a rattling noise which seems to come from the exhaust valve. I discovered a slight sideways movement of the rockerarm and decided to remove the rocker box.
There is a clearence of about 3mm on the exhaust side (pictures) and clearence of about 1mm on the inlet side. The spindles, boxes and arms show no signs of wear.

Image
Image

After some research I found out that later models had a spring on the spindle between arm and box. Concerning the parts book this spring is not provided on my engine (built 1941). Besides I guess the clearence is not adequate to fit the spring.

Does anyone have any advice what to do?

Best Regards
Christian

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Re: W/NG rocker box - clearence?

Postby dave.owen » Sun Nov 08, 2015 7:15 pm

I believe there is s hard steel washer missing
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Re: W/NG rocker box - clearence?

Postby christian.mutke » Mon Nov 09, 2015 8:54 am

Hi Dave,
you're right I guess. I hadn't thought about this simple solution :D The washer is missing on both sides. I was wondering because of the different clearence of inlet and exhaust. Therefor the washers were individual?
Hard steels means quenched and tempered steel?
Chris

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Re: W/NG rocker box - clearence?

Postby dave.owen » Mon Nov 09, 2015 10:56 am

Try Peter Kemp ,single spares or Drags

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Re: W/NG rocker box - clearence?

Postby Steven.Carter » Mon Nov 09, 2015 12:51 pm

Welcome Christian
It's nice to see a variety of hair styles in this thread :D

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Re: W/NG rocker box - clearence?

Postby christian.mutke » Mon Nov 09, 2015 3:33 pm

Haha, you're welcome, Steven :lol:

Thanks Dave! Drags got the part listed. Should be 945A-31.
Since I need some other bits I may write an e-mail to Peter Kemp as soon as I got my list completed.
Chris

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Re: W/NG rocker box - clearence?

Postby nevhunter » Mon Nov 09, 2015 11:03 pm

The W/NG ran the hardened steel washers, which are about .125 (1/8) thick. Same for both rocker boxes. The shaft comes hard against the washer held there by the oil pipe acorn nut. The other end is larger so the rocker is trapped between the washer and the large dia section of the shaft. If the end float is not enough, oilstone one end of the rocker face, carefully. Normally a couple of thou is enough float. Nev

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Re: W/NG rocker box - clearence?

Postby Vincent.vanGinneke » Tue Nov 10, 2015 12:14 am

Welcome Christian,
sorry for jumping this..... Nev, I think later engines had short springs there ?
or am I mixing up things ?
If so, could with later engines move the rocker a bit from side to side in order to get the valve rotating...or ?

Steven yes!, we need more hair do's, I'll try to make a new flashy one of meself......just tell me if I should not......

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Re: W/NG rocker box - clearence?

Postby christian.mutke » Tue Nov 10, 2015 8:06 pm

Thank you Nev! The float would have been my next question therefor this helps me a lot :)
Guess I have to find out next why the clearence of the inlet is only 0.04" even without the washer.

Hi Vincent, the box in the picture should be a later model. I think after 1952 they had these spring. My first idea was that maybe the rockers after 52 were different to those before 52 and I've got a spare from a later model fitted. It might well be... my W/NG is some kind of Frankenstein's Monster.
Chris
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Re: W/NG rocker box - clearence?

Postby nevhunter » Wed Nov 11, 2015 1:19 am

You have a spring there but the washer goes on the other side (The oil feed side) and the spring is removed. WNG rocker boxes are not polished anywhere originally. They are as cast.. The end float is determined by the shaft distance that is machined for the rocker to fit on. I think there are two (2) types of shaft. The "normal" ones have a spring which is considered quieter in operation. For competition work I would prefer no spring I never hear any unpleasant noise from the top of my W/NG..Nev


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