Date: Sun, 8 Oct 1995 00:11:57 -0500
Sender: Vanagon Mailing List <vanagon@vanagon.com>
From: cheeses@arn.net (Cheese)
Subject: Re: Checking Hydraulic Lifters
>Howdy all
>
>I have some lifter clatter on the '80 Vanagon I'm getting rid of. But
>I'm driving it on a daily basis until the person buying the engine has a
>chance to drive it. But I noticed a clatter like a valve tapping. So I
>checked it last week and found an adjusting screw that had flattened. So
>I replaced it. But there's still some clatter, and it seems like the #4
>intake valve is kind spongy. I think the lifter has been bad since it
>came from GEX, the reciepts say that there was lifter niose at about 400
>miles, and the valves were readjusted. And that there was noise at take
>off at about 1000 miles, but that they didn't see a problem.
>
>Does it seem like it's a bad lifter?
>Or how do you check if a lifter is bad?
>
>Bradley
>
Bradley,
My '79 Bus had a couple of noisy lifters that I quieted down for a while
with a pint of Dextron II with every oil change. Admittedly, not the best
fix but it worked for a while. BTW, if, when pushing on the push rod with
your hand, the lifter seems mushy, that's a sure indication of a hydraulic
lifter that's not doing its job. There should be a firm feeling when you
push. It's almost impossible to get an accurate valve adjustment with a
dirty/clogged lifter.
Finally had to break down and replace all the batterd valve adjustment
screws (can't just file the ends back to roundness; they'll wear out in a
few hundred miles, the tips on new ones are hardened). I then removed the
push rods and push rod tubes, and took all eight hydraulic lifters out,
keeping them in the proper order.
When I took them apart, they were full of grit and greasy, burned gunk.
Soaking everything in naptha and using a couple of old toothbrushes and a
soft brass "toothbrush" cleaned them up nicely. That Chemtool spray stuff
helps break up the gunk, too. I "bled" the assembled lifters while they
were immersed in a small, wide-mouthed jar of motor oil, pushing down the
little ball valve with a pointed object to get all the air out. I also took
the opportunity to clean the lifter bores with lots of motor oil and a
cotton cloth.
I then reassembled everything, reinstalled the lifters, tubes, push rods,
retorqued the bottom four head nuts, replaced the rocker arm assemblies and
adjusted the valves (engine cold, two full turns in, after just making
contact with the end of the valve stem).
Some mechanics just install the hydraulic lifters without bleeding them and
let the engine oil pressure pump them up. I don't see how they can get an
accurate adjustment that way though, at least without readjusting them the
next morning.
Anyway it ran lots more quietly and had more power after that. I think that
the affected valves weren't opening fully and robbing me of horsepower.
I've since replaced the engine but I think I'll rebuild the original one
(136,000 miles) to keep as a spare.
P.S. Don't use cheap oil. Change the oil and filter often and you won't
have to deal with this problem for a long time.
Cheese
'79 Bus
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