Valve adjustment question

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Hugues
Switzerland
Posts: 68
Joined: Tue Nov 29, 2022 6:08 am

Valve adjustment question

Post by Hugues »

Hi guys
I have a 710M and would like to check my valves adjustment gaps.
The Pinz repair manual says that I need to measure the gap on the cylinder 1 valves when the cylinder 4 valves “overlap”.
What is meant by “overlap”?
Hugues
From Switzerland
compunerdy
United States of America
Posts: 228
Joined: Wed Feb 13, 2013 12:04 am
Location: Idaho Falls, ID

Re: Valve adjustment question

Post by compunerdy »

This looks like a good thread on the procedure.

http://real4x4forums.com/PinzgauerBBS/v ... ent#p88722
Tim
1975 710K
pinzinator
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Joined: Thu Jul 29, 2004 3:12 pm
Location: Indio, California

Re: Valve adjustment question

Post by pinzinator »

Overlap is the position of the cam when both valves are completely closed.
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Hugues
Switzerland
Posts: 68
Joined: Tue Nov 29, 2022 6:08 am

Re: Valve adjustment question

Post by Hugues »

pinzinator wrote: Sun Dec 17, 2023 8:30 am Overlap is the position of the cam when both valves are completely closed.
Yes, although this situation happens more than once per cycle, i just realised today.
I think the overlap position the Pinz manual is referring to is the following:
"the overlap position for a given cylinder is when its exhaust valve is almost closed, and the intake valve is just starting to open."

This is the position you can see near the beginning of this online simulation:
https://www.geogebra.org/m/fmhfXxu9#material/fCHTsj4R
and pictured below:
overlap.png
overlap.png (186.27 KiB) Viewed 815 times
I have managed to adjust my valves today, a few were around 0.3mm rather than the 0.20mm prescribed in the Pinz manual.
And indeed, when you place cylinder 1 at TDC, cylinder 4 valves should overlap, as described above, so exhaust valve is almost closed while intake is starting to open, this is what I observed on my Pinz.
Hugues
From Switzerland
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