Rattle

[muskrat]

G'day GB.
It certainly wouldn't help the problem.
One other thing to check is that at half lift of the valve the tappet is inline with the stem. After years of valve grinds and rockerbox facing you may need thicker gaskets. This is where the copper gaskets in varying thickness's from Lani at Coppergaskets Unlimited come in handy. https://tinyurl.com/y5gj5z8a
Cheers

[Swarfcut]

GB.  At least you found something that was not quite right. When measuring the springs yesterday I noticed that there were witness marks on the valve spring caps where they had rubbed on the underside of the rocker arms, so it's a bit tight for space in there anyway, and cylinder height, rocker box refacing and head skimming all alter the geometry from standard. Don't forget to check pushrods for a bow.

 Swarfy.

 Additional. Thinking about it, if the valve clearance was too big, the underside of the rocker would just touch the valve cap before the tappet contacts the stem, so maybe in this case the engine had been run with a rocker box just on the limit for mating face height.

[Greybeard]

G'day GB.
It certainly wouldn't help the problem.
One other thing to check is that at half lift of the valve the tappet is inline with the stem. After years of valve grinds and rockerbox facing you may need thicker gaskets. This is where the copper gaskets in varying thickness's from Lani at Coppergaskets Unlimited come in handy. https://tinyurl.com/y5gj5z8a
Cheers

Musky, will you clarify 'tappet is in line with the stem' please.

[Greybeard]

... cylinder height, rocker box refacing and head skimming all alter the geometry from standard. Don't forget to check pushrods for a bow.

This engine has not had much work done to it; it was off the road for more than thirty years.
I have SRM pushrod. I've rolled them, they are straight.

[chaterlea25]

Hi GB,
Could you post a few photos of the valve spring components?
If the wrong top of the spring components were fitted maybe the same happened with the bottom  cups/ washers ??

Iron head cup

https://www.draganfly.co.uk/index.php/component/hikashop/product/14340-

Alloy head "cup" washer

https://www.draganfly.co.uk/index.php/component/hikashop/product/14797-

Compare the number of turns on the springs and the wire diameter?

John

[berger]

as musky says it will not help, also the inner valve spring is under a lot more compression with the spring collar upside down, it sits on top of the ridge instead of in the recess so both springs are a lot more compressed

[berger]

john 67- 0886 is super rocket and road rocket,  67-0033 is A10/ A7ss A7 and plunger A's

[muskrat]

G'day GB.
The tappet (screw in bit to adjust gap) and the valve stem should be in a straight line at mid lift.
Picture attached has the adjuster on the pushrod end but shows what I mean.
Cheers

[Greybeard]

G'day GB.
The tappet (screw in bit to adjust gap) and the valve stem should be in a straight line at mid lift.
Picture attached has the adjuster on the pushrod end but shows what I mean.
Cheers

Cheers m'dear

[Greybeard]

I've been in the shed this morning. I took some general photos while I was working.

I took a video of the affected, (badly worn cam follower) nearside inlet valve, then the offside, for comparison. Both sides seem to me to have a reasonable range of movement when the rocker is fully depressed. What are your opinions on this?

I've decided that the valves collets are ok. They do not protrude below the collar and they do wedge into place and stay there.

https://www.dropbox.com/sh/32ch005fksuk6t6/AABJ2zv85KBL25tceLoZ6u_Ra?dl=0

The head is torqued down. There is no rocker box or cylinder base gasket on at the moment. The rocker box is only held down by the four long bolts. I've set all gaps to 8 thou.

[RDfella]

Was unable to open the video attachment, but if the valve will open further beyond full lift on the cam, then the problem is not binding as SRM suggest, but poor quality cam followers

[Swarfcut]

GB.. Your collets protrude above the flat area of the spring cap. The head I examined had  the top edge of the collets lying level with or slightly below the centre of the valve cap, in effect  increasing the fitted length of the spring. If your video demonstrates the whole of available spring movement, that looked a bit on the small side in my experience.

 Swarfy.

[Greybeard]

GB.. Your collets protrude above the flat area of the spring cap. The head I examined had  the top edge of the collets lying level with or slightly below the centre of the valve cap, in effect  increasing the fitted length of the spring.

What do others think about that? The previous camshaft, of course, didn't lift so high so the collet position may not have had any detrimental effect.

If your video demonstrates the whole of available spring movement, that looked a bit on the small side in my experience.

No Swarfy, that was additional movement after the spring was fully depressed by the camshaft.

[berger]

swarfy all the valve collars and collets I have sit flush or a tad above but not as much as greybeards do, having said that the position of greybeards wouldn't be helped with the bottom collar on upside down. BUT were both bottom collars on upside down or only one Mr greybeard? if both I still say it was /is a shit follower.

[Swarfcut]

GB. My mistake, I thought the video demonstrated total valve spring movement.   What it shows is more than adequate additional spring movement available after full camshaft lift, so in the grand scheme of things looks to be a soft follower is the likely culprit. Did you have time to compare any measurements with the ones from my sample head?

 bergs. Interesting that there appears slight variation with collet and cap, above, level, below. Any other folks got one apart to check?
 Swarfy.