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Piston Projection question?

Posted: Sat Dec 14, 2013 8:12 pm
by Rudy
Piston projection question?

I am working on my 1983 1.6 D with 12mm mechanical head.

The block has been bored 40 over and the top of the block "decked" 2 thousands
I have installed KOLBENSCHMIDT 1600 Turbo Diesel pistons and piston projection on pistons 1-3 & 4 is 79-80 mm yet number 2 piston is 82-83 mm.

In addition, I bought a remanufactured KOLBENSCHMIDT cylinder head and it looks like the head surface was cleaned up some.

originally my engine had a 3-notch head gasket is that what I should go with or would I need the 4 notch head gasket?

Thank you for your time.
rudy

Re: Piston Projection question?

Posted: Sat Dec 14, 2013 8:46 pm
by TylerDurden
A Bentley service manual is worth its weight and price.

Bentley say for mech heads with .81mm - .90mm protrusion a 2-holer is the shot.

What's with the oddball height?

Re: Piston Projection question?

Posted: Sat Dec 14, 2013 9:01 pm
by Rudy
thanks Tyler
don't know why number 2 is off

Re: Piston Projection question?

Posted: Sat Dec 14, 2013 10:00 pm
by Quantum-man
That seems like a big difference, but is only 1 to 1.5 thou and might be a variation in the big end shell bearing area.

Re: Piston Projection question?

Posted: Sat Dec 14, 2013 10:27 pm
by Rudy
TylerDurden wrote:A Bentley service manual is worth its weight and price.

Bentley say for mech heads with .81mm - .90mm protrusion a 2-holer is the shot.

What's with the oddball height?
P.S.

Tyler

Found the spec in my Bentley book page 24 I was looking at the wrong year car!

And yes it calls for a 2 notch however it ran well with the 3 notch before

Yet, numbers don't lie it does call for the 2 notch………….

Again thanks for your time.
Rudy

Re: Piston Projection question?

Posted: Thu Dec 19, 2013 11:55 pm
by Fatmobile
How much cleanup on the head surface?
I like to remove the cam caps and buckets to see if the cam rocks in it's saddles, or how much it rocks.
Good wasy to see how much the head is warped.
Good chance to look at the cam journals and check wear,.. they can look pretty bad at times.
I know it was rebuilt but I had a head rebuilt, actually bent straight and line bored. After startup the cam clearances were too loose and I was losing oil pressure.
Whole story is in the black GTI build:
viewtopic.php?f=20&t=5570
in the project fora.