Head gasket with comb

[Swarfcut]

 Well, never having seen one in the flesh, I reckon incorporating the pushrod comb profile into the rear gasket could be the madcap idea that changes the world. Longstroke design is different, but similarly here the head gasket offers more lateral support to the pushrods and aids rocker box fitment.

 Swarfy.

[Minto]

Exactly that!
They stay where they're supposed to and don't tare when you prod around with various implements in the gap between the head and box.

[Roger (Doomtrainbarx)]

Well, never having seen one in the flesh, I reckon incorporating the pushrod comb profile into the rear gasket could be the madcap idea that changes the world. Longstroke design is different, but similarly here the head gasket offers more lateral support to the pushrods and aids rocker box fitment.

 Swarfy.

Now that would be a good idea !! - if only.

[Greybeard]

Well, never having seen one in the flesh, I reckon incorporating the pushrod comb profile into the rear gasket could be the madcap idea that changes the world. Longstroke design is different, but similarly here the head gasket offers more lateral support to the pushrods and aids rocker box fitment.

 Swarfy.

How could you guarantee the pushrods would not rub on the gasket when the job is done?

[Swarfcut]

 Like I said, madcap idea but simple in concept. Were not talking a precision sliding fit for the pushrods, more of a foolproof way of holding them more or less in the right place, so the box drops straight on. There can be considerable leeway between the gasket and pushrods, and only the rear edge of the front of the rockerbox gasket needs to support the pushrods as they naturally fall forwards. Time for the cardboard template for you experimenters. I mentioned the Longstroke, here the pushrods are some 6mm in diameter, passing thro' a 11mm hole in the head gasket. Hardly a tight fit but aids assembly well enough.

  The possibility of relatively soft copper being rubbed away is of no real consequence, more harder materials end up in the oil and sediment out, and these days oil filters are more commonly fitted.

 Swarfy.

[Greybeard]

It surprises me that that idea hasn't been tried before. Maybe having difficulty fitting the rocker box is really only applicable to us old geezers. The young'uns with nimble fingers, good eyesight and good knees were probably not phased by the job.

[RDfella]

The young'uns with nimble fingers, good eyesight and good knees were probably not phased by the job.

They all drive cars

[Greybeard]

The young'uns with nimble fingers, good eyesight and good knees were probably not phased by the job.

They all drive cars

Well I meant back in the day. Did we worry about jobs like that when we were 20? I would have been in the road, working on my combo.

[muskrat]

G'day Swarfy.
I had often thought of that. The holes for the pushrods would only need to be 2 or 3 mm larger than the pushrod to avoid rubbing. The cups in the rockers would centralize the rod if not too far out.
Now all we need is a drawing for Lani at https://coppergaskets.us/ to make them. He does my head gaskets modified for the through bolting. https://tinyurl.com/yh8vjcwn
Cheers

[Minto]

Great! Just when I'd got doing this down to a 5 minute job someone comes along with a genius idea to render my technique redundant. Story of my life.

[RDfella]

Happens to us all. In the 70's I was doing a lot of rebuilding of a certain 6L Ford diesel engine. I decided a bit more lubrication of the cylinder wall wouldn't go amiss, so I drilled a conrod to achieve that. However, I realised the oil squirt wouldn't be timed appropriately because the crankshaft oil hole didn't co-operate. The only way seemed to be a  hole elongated by 1/2" in the upper big end shell. Duly made a jig to drill the rods and carried out that mod for a while.
Then, about a year or so later, Ford brought out a modified conrod - complete with an upper bearing containing an elongated hole. Always thought Ford must have been looking through my workshop window.......

[RichardL]

If this is seen as an important feature to go with solid copper gaskets. might as well just make holes in a continuous gasket (with extra oil drain holes, of course).  Maybe adds 25¢ for the unrecovered scrap, but who's counting? Maybe it doesn't need to be copper if it's continuous.

Really, unless you are mounting rocker boxes all the time, the basic comb does most of the job. Not saying it's not fiddly, but it's not BIG DEAL fiddly. C'mon, do we really want to lose this bit of the mystique?

Richard L.

[groily]

Somebody here - sorry but I've forgotten who, it was while back - suggested using a comb suitably bent and then clamped to the top cyl head fin.
Following that advice I found rocker box fitting was a one-shot drop-straight-on affair ever after, and held no further horrors. Simplest ideas can often be best.
I wish I could find a similarly easy way for Notruns, which with engine in frame I have always found much harder.

[Swarfcut]

   Should have patented the idea and kept my mouth shut, then sold out to some venture capital outfit.

   My thought was to modify the rear rockerbox gasket, but somehow the topic has morphed into a change to the head gasket. This is perhaps not so good, as this could obstruct oil return to the followers. Probably academic, I'm sure there is enough oil and mist swirling around. The key to all of this is the ability to produce good gaskets that seal properly using CNC techniques. The material cost over a standard profile gasket is zilch, and if anyone pulls it off there is an obvious market for a product with this USP. Put me on 15%

 Swarfy.


 Additional. Off today to the local FolkEast Festival. Fully vaccinated but well aware that I can still catch a dose. Buying a new Rain Poncho on the way, and looking at the forecast I reckon GB should investigate weekend Van Rental!

 Have yo'sel's a good time whatever you're up to.

[BigJim]

Oops. Will tell GB all about it tomorrow if we don't drown!