Date:         Sat, 4 Oct 2014 19:18:47 -0500
Reply-To:     mcneely4@COX.NET
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Dave Mcneely <mcneely4@COX.NET>
Subject:      Re: drive from Oklahoma to Spokane, WA
Comments: To: mark drillock <mdrillock@COX.NET>
Content-Type: text/plain; charset=utf-8

Mark, thanks.  Would the CV joint/axle be more likely to knock under the conditions I experienced?  I was prepared to think it was an engine knock simply because of the conditions.  The knock did not recur at other times, and then reappeared when I climbed another steep grade.  I'll have everything checked when I get settled in at Spokane.  Meanwhile, I won't be driving the beast all that much, anyway.  As DeanB suggested, I'll switch to a synthetic oil, too.  After all, for one or two oil changes a year, the cost is trivial compared to tearing up an engine. If it makes a difference, it is cheap insurance.  mcneely

---- mark drillock <mdrillock@COX.NET> wrote:
> Given your descriptions I would put a knocking CV joint/axle at the top
> of the list. Just about every other moving part turns too fast. Wear in
> a CV joint can result in a rhythmic knocking sound. Assuming that is it
> the good news is that it probably isn't an impending doom just yet and
> isn't all that expensive to fix.
>
> Mark
>
>
> Dave Mcneely wrote:
> > Mark, this may be the  most astute query anyone has made.  I did not time the frequency of the tapping sound, but did think about it, and thought that it should have been more frequent if it was one of the parts you mentioned or a bearing. But the sound itself did make me think it was engine, not chassis or drive system.   It actually was more on the order of a few times per second, rather than several tens of taps per second.  So it might be more likely to be a drive system component rather than an engine component?  I think I just need to get it in to a good Vanagon mechanic.  But to reproduce the conditions might require waiting till late spring, as I will not be where the van is until mid to late November, and don't expect warm weather any time real soon after that.  Dave
> >
> > ---- mark drillock <mdrillock@COX.NET> wrote:
> >> What was the frequency of the sound you heard? At 3400 rpm the engine is
> >> turning almost 60 times per second. Valves, lifters, pistons, and rods
> >> are each stressed most at half that frequency, so 30 times per second.
> >> At 45 mph CV joints/axles rotate at about 9 times per second.
> >>
> >> Mark
> >
> > --
> > David McNeely
> >

--
David McNeely