Valve sitting

[scottie]

Hi everyone,
I have a 1776 engine with chrome push rods does anyone know the valve settings in mmm.

Thank you

 

[sparkywig]

Cromoly pushrods usually have a loose zero setting. This means zero gap between the rocker and pushrod, but with a clearance that allows you to spin the pushrod with your thumb and forefinger. This will give you 0.000" at room temp, and 0.004-0.006"/0.1-0.15mm gap when fully warm.
You could try 0.01"/0.02mm to be on the safe side.
Ask the engine builder what he recommends?

 

[scottie]

Thank you sparkwig great information, I have set them at 0.02mm but when I took it for a test drive only 4 miles the engine was extremely hot and the valves were tapping making me thinks it not set correctly. I did ask the engine builder but as it been 4 years ago he cannot remember.

 

[K@rlos]

Set at loose zero like sparkywig said. Reason for this is chromoly has different expansion rates. However I will warn you, moly push rods are noisy even when adjusted correctly. They are generally used in more highly strung engines with duel valve springs and aggressive cams due to their extra strength over aluminium rods.

 

[scottie]

Hi K@rlos thank you, that migh explain the tapping noise in the engine however the engine bay was extremely hot, I don't know if that was down to the weather or I hadn't set them right as I said to sparkwig I set them to 0.02 for some reason my feeler gauge is in mm.

 

[K@rlos]

Stock is 6 thou 0.02mm is 7 thou so not exactly a million miles out. I’ve always run moly push rods at loose zero and my motor has never ran hot. What distributor do you have and what’s your timing set too?

 

[StefansBus]

Stock is 6 thou 0.02mm is 7 thou so not exactly a million miles out. I’ve always run moly push rods at loose zero and my motor has never ran hot. What distributor do you have and what’s your timing set too?

I think you have got one too many zeros in there. 0.2mm is 7.8thou. Stock is 0.15mm or is just under 6 thou.

Stefan

 

[K@rlos]

Stock is 6 thou 0.02mm is 7 thou so not exactly a million miles out. I’ve always run moly push rods at loose zero and my motor has never ran hot. What distributor do you have and what’s your timing set too?

I think you have got one too many zeros in there. 0.2mm is 7.8thou. Stock is 0.15mm or is just under 6 thou.

Stefan

Yes it appears I have, my mistake :lol: