Date: Sun, 15 Apr 2007 12:02:13 -0700
Reply-To: Robert Fisher <refisher@MCHSI.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Robert Fisher <refisher@MCHSI.COM>
Subject: Re: leakdown test
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I think the relatively odd design of the WBX makes it a bit of a different
application/situation than it would a V8, for instance. However, to my mind
the more (good) information you have the better off you are; I certainly
don't like to waste time doing exploratory surgery and experimenting.
If you're going to do either test it isn't much extra trouble to do the
other one while you're at it, at least with my set up- do the compression
test, manually turn the engine back to TDC for that cylinder, pop the gauge
off the hose, put the leak-down portion on, do that test and move on to the
next cylinder. Write down the numbers and note where you heard what and
you've got a pretty decent picture of what's going on without removing
anything more than the spark plugs and the dizzy cap. As far as I'm
concerned that beats the hell out of opening the thing up and poking around.
TETO.
Cya,
Robert
----- Original Message -----
From: "Benny boy" <huotb@VIDEOTRON.CA>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Sunday, April 15, 2007 9:32 AM
Subject: Re: leakdown test
> What is the point of leak down test? if you have bad compression you have
> a
> problem anyway! the engine need to be open!
>
> If you are curious about where is the leak is, just pop out the valve
> cover
> and look at valves height,
> http://www.benplace.com/bjp_head1/29-11-05_1848b.jpg
>
> If the are even, your problem is on the pistons side or or the gasket
> side,
> anyway, your up for a re-seal, burned valve/seat always show on the valve
> height.
>
> You burn oil= pistons side, now, forget about new rings, it's way more
> labor
> to do so and unless the top compression ring is broken, news rings won't
> fix
> anything.
>
> EX: removing old pistons, 1 hour, working on the cylinder and pistons to
> prep them for new rings, a good 2.5-4 hours + another 75$ for new rings,
> (those always have to be gap, rings groove need cleaning), thats (in the
> US
> and not at my cheap rate) more than 300$ in labor, new pistons kit are
> ready
> to slide in. I have check ring gap for 2 years on new pistons (Brasil)
> kit,
> the gap as alsway been perfect, i don't check them anymore. So that said,
> new pistons kit are 400-500$ Forget about ring position, they move anyway.
>
> Bottom line, it cost too much to the customer trying to save old pistons.
>
> If you are ready to open an engine, put new heads & pistons, you will have
> some peace of mind for a wile.
>
> Lately, when a top-end or a semi top end or a re-seal is needed, i explain
> to the customer that if i mess with pistons, he is better off with new
> one.
>
> In my book, engine open = new heads and pistons... MINIMUM. If a cutomer
> is
> ready to pay 20-30 hours, he should be enough intelligent to put new stuff
> in.
>
> lately, cam are pitted, and that another newer problem, in the last 3 core
> i
> had to open, center camshaft bearing where shot. this is a classic bottom
> end problem with 2.0L AC engine, i think old wasser are getting there
> also.
>
> Anyway, sorry if i sound crude but it's sunday and i have my hands full in
> 2
> open core, and that is what i'm seeing. The 2.1L in front of me as a crack
> in the second crank bearing (from back, pulley side). You should see all
> the
> coolant trace in that block. I had so much metal at the bottom of the case
> that i had no choice to check the crank bering. Now i have to call the
> guys
> to tell him that bad news. That is another customer van who will leave the
> shop with the engine in pieces in the passenger area of the van, i know
> now
> that he as not enough money to fix the engine.
>
> The short story, engine are getting old.
>
> I'll show you a few pics later.
>
> Cheers, Ben
> http://www.benplace.com/pistons_heads_video.htm
> ps.: you will say, well that page show that you do try to save pistons,
> yea,
> of course, i make more money :-)))) no joke, that job cost more than to
> have
> put new pistons, we learn each day.
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