'56 G80CS Inlet valve Oil Feed?

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'56 G80CS Inlet valve Oil Feed?

Postby Matchymarty » Sat Oct 07, 2017 6:31 am

Hi all,

Fiiiiiiiiiiiinally putting back together my '56 Short Stroke. I've had the head done, and new guides made and installed. It seems however, whilst I was cleaning it and blowing out all the holes, that no air came out the inlet valve guide. Surprise surprise, there is no hole - as fed by the inlet oil feed regulating screw orifice.

I can't remember if the original guide had a hole or not.

Is the '56 G80CS supposed to have a inlet valve guide oil feed hole? I'm not sure... as I seem to remember someone telling me that the short strokes didn't have one..... though my memory is not all it's cracked up to be...

Anyone ?

Cheers.

Marty

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Re: '56 G80CS Inlet valve Oil Feed?

Postby Rob Harknett » Sat Oct 07, 2017 3:02 pm

Check your 56 parts list. For adjusting screw it does state "all " models. Still there in 59 note in parts drawings a hole is shown in the guide.

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Re: '56 G80CS Inlet valve Oil Feed?

Postby ajscomboman » Sat Oct 07, 2017 3:46 pm

My 56 CS's have an oil hole in the inlet guide.

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Re: '56 G80CS Inlet valve Oil Feed?

Postby cbranni » Sat Oct 07, 2017 5:56 pm

Mine too

Colin
only dead fish go with the flow

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Re: '56 G80CS Inlet valve Oil Feed?

Postby ajscomboman » Sat Oct 07, 2017 6:03 pm

ajscomboman wrote:My 56 CS's have an oil hole in the inlet guide.


Further to my original posting I would add that the oil metering screw is all but screwed right in and not 1/6th of a turn out as per manual without any adverse effects.

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Re: '56 G80CS Inlet valve Oil Feed?

Postby Matchymarty » Sat Oct 07, 2017 7:55 pm

Thanks all,
I had checked my parts list, and it indeed shows the hole and screw. Though, I had heard from an 'old guy' that they may not have used the hole in the guide on comp models.

I may have to check with the head machinist, but perhaps he put in guides that do not need addition oiling?

Also, interestingly, how is it that the exhaust valve does not get oiled as it is the one that gets hotter?

Cheers.

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Re: '56 G80CS Inlet valve Oil Feed?

Postby SPRIDDLER » Sat Oct 07, 2017 8:43 pm

Matchymarty wrote:Also, interestingly, how is it that the exhaust valve does not get oiled as it is the one that gets hotter?


I believe that part of the reason is that the oil for the inlet valve stem is being constantly washed away by the incoming fuel/air mix.
Zorst valves were (still are?) made from a different material from the inlet. The early zorst valve stems were hollow and contained some type of sulphur compound which was intended to carry heat away from the valve head.
I'm not aware of any guides made from a material that doesn't require oiling.

It seems odd to me that the zorst stem gets any oil at all from the puddle in the rocker box via the hole in the valve guide since one would think that on the zorst stroke when there is positive pressure in the cylinder (and the zorst valve is open) it would tend to 'blow' any oil back up through the clearance 'twixt the valve stem and its guide............ :?
What if the Hokey-Cokey is what it's all about?

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Re: '56 G80CS Inlet valve Oil Feed?

Postby Rob Harknett » Sat Oct 07, 2017 11:00 pm

This has been discussed before. I believe the exhaust side is where oil enters the top of the rocker box, some gets channelled to the exhaust valve enough to lubricate it.

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Re: '56 G80CS Inlet valve Oil Feed?

Postby Rob Harknett » Sun Oct 08, 2017 10:42 am

Rob Harknett wrote:This has been discussed before. I believe the exhaust side is where oil enters the top of the rocker box, some gets channelled to the exhaust valve enough to lubricate it.

You had already been told that on the yahoo e group forum. Once again the machines literature also gives the answer. There's a diagram in the Instruction book that shows oil entering the rocker box and how parts are lubricated along the way as oils drains back to the sump.

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Re: '56 G80CS Inlet valve Oil Feed?

Postby Matchymarty » Mon Oct 09, 2017 7:20 pm

Rob Harknett wrote:
Rob Harknett wrote:This has been discussed before. I believe the exhaust side is where oil enters the top of the rocker box, some gets channelled to the exhaust valve enough to lubricate it.

You had already been told that on the yahoo e group forum. Once again the machines literature also gives the answer. There's a diagram in the Instruction book that shows oil entering the rocker box and how parts are lubricated along the way as oils drains back to the sump.


Yes, Thanks Rob.
I've checked my manuals. I'm merely trying to make sure the manual is correct, as according to the old guy I mentioned, the factory did many different things here and there, and particularly with the Comp models.
I just wanted to be sure, before I take the head back to the engineer and get him to put a hole in the new guide.

Cheers.

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