Bleeding the valve lash adjusters?

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codfizzle
First Gear
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Bleeding the valve lash adjusters?

Post by codfizzle »

Has anyone ever done this? In my FSM, it outlines a procedure for bleeding air out of the hydraulic lash adjusters. So how does one get air in the lash adjusters in the first place? What are some symptoms of air being in the adjusters? My valve lifters have been tapping a little lately, and they never did this until about a week ago. Could this be because there might be compressable air in the lash adjusters, slightly messing up their clearances? Because if there is even a tiny amount of air in there, it seems like it would affect the valve opening and closing clearances. Also my engine's been running really rough lately, could this be a symptom of the valves not opening or closing correctly due to air in the lash adjusters? Anyone ever done this? What was the outcome?
Bdub
Second Gear
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Joined: Mon Nov 12, 2007 1:59 am
Location: Connecticut

Post by Bdub »

They collapse. The rubber over time gets kind of spongy and no longer holds the oil in like it should. Once you get to the adjusters, You can remove the oil, and manually fill them back up, but once they start leaking, it seems the fix is only temporary.
I've actually done this, and after all my work, it still didn't go away after fixing a couple and even replacing a decent amount.

I am not sure what climate you are in, but if it isn't crazy cold, start with a thicker oil. In my N/A 2.2 I ran 10w-40, and then had awesome luck with Valvoline Super Blue diesel grade 15w-40. The ticking predominantly went away after I ran the thicker oil. I had no problem using it in winter CT climates.
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