Technical Valve guide installation height

[Vikingsen]

Hi

Im restoring a 650 engine, I have 2 engines which I disassembled and noticed the same fault on both engine heads. The same valve guide has dropped down into the exhaust output. Is this a common problem or just a coincidence?

Now, when im installing new valve guides i can't find any info on the installation height. Other that the correct Fiat tool will take care off this, which i don't have. Any how know the right height?

Allso, any thoughts about valve guides and porting.

 

[bugsymike]

Can you go by the marks on the old guides you removed re depth when installed.
I was going to suggest asking hobbler as highly experienced in that direction, but cannot locate?

 

[Vikingsen]

Can you go by the marks on the old guides you removed re depth when installed.
I was going to suggest asking hobbler as highly experienced in that direction, but cannot locate?

I did mesure the height. 20, 18 and 17mm, i guess I have to by eye. My best guess is, it's not crucial with the height, as long as the valve moves freely, it must be a question having the guides entering the flow tubes as little as possible

 

[bugsymike]

I did mesure the height. 20, 18 and 17mm, i guess I have to by eye. My best guess is, it's not crucial with the height, as long as the valve moves freely, it must be a question having the guides entering the flow tubes as little as possible

That's true , but also don't want it to foul top of spring collet holder area, so maybe put a valve in position without the spring and measure movement both ways including any valve stem oil seal.
There are several who have tuned up versions on Forum maybe they can advise.