How do you know when to do an adjustment on the valve lash? I have a B7100 with 1300 hrs, a B6200 with 2300 (guessing) and my son has a b6100 with unknown hours.
John in VA
John in VA
Valve Adjustment?
- Thread starter 300zx
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The obvious one would be one would hear them tapping if loose.
If they are tight the engine would run uneven which is harder to diagnose as it could be caused by other causes.
In the absence of any symptoms I check the clearance as part of bi anual service which for my b7100 is around 100 hours but as a matter of course on a new purchase
.
Dave
Lil Foot
Well-known member
Lifetime Member
Equipment
1979 B7100DT Gear, Nissan Hanix N150-2 Excavator
When I got my B7100, previous owner maintenance was at best, suspect. I did not think that it ran rough or that the valve train was noisy, but I was stunned at how much smoother & more quietly it ran after adjusting the valves. I would check & adjust them (if necessary) just to establish a baseline. Mine were all loose, & a couple were .020-.022. 
If you slacken the retaining nuts off, give the cover a sideways tap with a rubber hammer and it comes loose,you'll probably get away without a new one.
dave
That's IF the valve cover has ever been off. I don't think the vavle cover had ever been off on my L175.
When we first got it running, you could tell the vavles needed adjusting; but just attempting to loosen the two vavle cover bolts made a change in the vlaves. Very strange, but it did lead to me discovering this very helpful website.
One of my first questions was to find out the proper vavle lash for my tractor.
Robert
You guys are right, the decompression lever was also way out of adjustment. The handle is broken from it, so right now I have the decomp adjusted to not touch anything. One of these days I will replace it and get everything in spec.
Going from memories (3 or 4 years anyway) my valves had anywhere from .016 to .022" clearance, when the book calls for .007-.009". I know the seat of the pants dyno said I gained about twice the HP when I had them set properly.
Robert