Valvolean

[Rog246]

Originally Posted by boxhead

Any idea as to the root cause?
To my eye and from camera angles, it looks like the rocker arms are very close to spring retainer?
Are your pushrods maybe a touch too short?

Push rod............what's a push rod !??!

Oh sorry, just realised its one of them Chevvy ARK thingies

Okay I've thrown the burley out...........who's gunna bite ???

[Aussie Mike]

Originally Posted by Rog246

Push rod............what's a push rod !??!

Oh sorry, just realised its one of them Chevvy ARK thingies

Okay I've thrown the burley out...........who's gunna bite ???

You've thrown the burley all over yourself. It's a Ford Windsor motor LOL

[Rog246]

Originally Posted by Aussie Mike

You've thrown the burley all over yourself. It's a Ford Windsor motor LOL

Faaarrk It's really hard to talk with a mouthful of crow feathers...........should have looked harder

[Gaz64]

I've had another look for some time, and the lifter for this valve failure also looks different in your photo compared to the other 7.

The pushrod seat in the lifter looks different.

Pushrod seat has come out?

Gary

[LoBelly]

Originally Posted by Gaz64

I've had another look for some time, and the lifter for this valve failure also looks different in your photo compared to the other 7.

The pushrod seat in the lifter looks different.

Pushrod seat has come out?

Gary

Wow - good eyes - and thank-you for taking the time to look for more clues

I have uploaded a better picture (below - you can zoom in by holding down Ctrl and scrolling up with your mouse)

The lifter looks different because it is not covered in oil - I suspect I wiped it as part of the general inspection - if you zoom in you will be able to make out the various parts of the lifter (as visible from that angle) and those parts will just be cleaner than the ones around it.

[LoBelly]

Originally Posted by Gaz64

Just to clarify...
..I would hope all of the valves were inspected for this condition.

Now this time, with the light spring fitted, every clearance needs to be checked, valve to piston clearance, retainer to rocker, rocker to stud etc, throughout the full 4 stroke cycle of the engine.

Gary

All the valves are new now - I was just looking for the itemised receipt - If I can find it soon I'll post a copy

Originally Posted by Bernica

I just hope you can find all those pesky little metal parts that went somewhere when it broke!

...what harm could they do...?

Originally Posted by Rog246

Faaarrk It's really hard to talk with a mouthful of crow feathers...........should have looked harder

Don't beat yourself up too much Rog - it shows why the LS is perfect for a replica cobra - because it is a replica windsor
(and like replica cobras - has 40 years worth of updates )

[Rog246]

Originally Posted by LoBelly

All the valves are new now - I was just looking for the itemised receipt - If I can find it soon I'll post a copy



...what harm could they do...?



Don't beat yourself up too much Rog - it shows why the LS is perfect for a replica cobra - because it is a replica windsor
(and like replica cobras - has 40 years worth of updates )

Well most of the DOHC ENGINES are made at the Windsor even though most people don't call them that........but hey.............'what's a pushrod ?" LOL

[Gaz64]

I should have mentioned this earlier.

Have you thought about going to beehive springs?

The technology is out there now with a lot of spring manufacturers.

Lighter springs, combined with a lighter retainer.

Would also give a little more clearance with the rocker arm.

Gary

[LoBelly]

Originally Posted by Gaz64

Wow, look at the bend in the valve stem.
Sheared off straight under the valve collets.
Thank god the piston is ok.
Can you see what I mentioned about the lifter for that valve in one of your early photos?
Or is what I see an illusion?

Gary

Hi Gaz
I think it might be an illusion - I just cleaned that lifter to get a good look at it to see if I could find anything wrong

Originally Posted by Bernica

Again, did you find the rest of it somewhere in the engine?

Hi Bernie -
As Gaz says the valve tip just sheared off so the 'rest of it' was retained by the collets in the top of the spring. Its in one of the earlier photos

Originally Posted by Gaz64

I should have mentioned this earlier.
Have you thought about going to beehive springs?
The technology is out there now with a lot of spring manufacturers.
Lighter springs, combined with a lighter retainer.
Would also give a little more clearance with the rocker arm.

Gary

That would have been a good idea - but the top-end is back together now and I have issues elsewhere to attend to...

ta
LoBelly