Date: Fri, 27 Mar 2009 13:46:08 -0700
Reply-To: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Subject: Re: diagnosis--blown piston ring?
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It's not the end of the world...........it's repairable , even with engine
in place.
it won't be a 'full rebuild good for 100,000 miles' or anything like that,
but..........
since oil is puking out of the dipstick, it's reasonable to assume the low
compression is from piston/rings on that cylinder, and not from burnt
valves.
The pistons and barrels are replaceable individually. ( boring or the
barrel isn't normally done, replacing the pistons and barrels in sets is
standard repair method )
But you could..........pull that head, engine in place in the car, and
remove that piston from the connecting rod ............... it's a little
tricky .........
the pistons are removed starting from the rear bumper end of the engine
..........that means #'s 2 and 4 are 'just one step' to remove'..........
pull up the barrel until the wrist pin clip is exposed, remove the clip,
pull the wrist pin out, remove the piston from the connecting rod - but
.......
for #'s 1 and 3, the 'forward' pistons, you remove those AFTER taking out
the piston and barrel 'in front of it' ......so it would help ease things if
the bad piston is at the rear of the engine, ........# 2 or 4. It helps to
heat the piston gently to get the wrist pin to slide out.
since you just need to keep it working half-decently for a year........you
can put on a good used piston and barrel in that one spot.
don't forget the rest of the engine could be 'close' to being pretty shot
too. Ideally, it's one bad piston/rings, and you still have 3 medium ok.
Also do valve work on that head too.
yes, disconnect the injector wire so you're not spraying fuel into that dead
cylinder, and diluting the oil with raw fuel.
it might be tricky to do in the street, especially with having to move it
every few days.
rod bearings........a weak area in 2.1's since the connection rod bolts
stretch, lowering oil pressure, after very high miles.
A lot of people would say your whole engine has had it, and you need a whole
new good used one, or a rebuilt.
If you don't mind hard dirty work, and possible limited life of the results,
it is patchable.
I sold a used piston and barrel for a 1.9 waterboxer engine to a guy about 2
years ago.......
that worked out just fine for him.
Though at 180,000 miles on a 2.1 ...........there's concern.
I'd say as long as you don't mind if it doesn't work perfectly forever,
.........and you don't mind hard grubby dirty work in the street.......it's
doable. There is risk for sure, even risk that you'll fix one cylinder only
to find out the others are close to death anyway.
it's a westy though..........always a valuable vanagon.
good used engine is your best option, if you can find one that's decent, and
at a fair price, and if you don't mind doing a whole engine swap in the
street, if that's the only place you can find to do the work. I'd say bring
it to my shop , along with your good used engine, and we'll do the swap for
a very fair deal., but I think you are too far away, considering how your
van is right now. I'm in the very southern end of Oregon.
Hope you get someting going that works for a while at least !
Scott
www.turbovans.com
----- Original Message -----
From: "Ben S" <phlogiston420@GMAIL.COM>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Friday, March 27, 2009 12:00 PM
Subject: diagnosis--blown piston ring?
>i was driving my 86 2.1L westy up to tahoe sunday night when i noticed
> oil on my rear window. pulled over and saw that at least a quart of
> oil had been blown out of the dipstick tube. engine was clearly
> running on 3 cylinders. i added oil and limped back home. last night
> i did a compression test. 150 psi in the cylinders that were firing,
> 0 psi in the one that was not.
>
> could this be anything other than a piston ring failure? is it normal
> for them to fail so catastrophically? engine has about 180k on the
> clock and everything looked normal in an oil analysis done about 2k
> miles ago. valve springs seem ok from visual inspection (is that
> enough?). is there anything else worth checking?
>
> how likely is it that i scored the cylinder wall or did other damage
> to the engine during my 30 mile drive home? will i further reduce the
> "rebuildability" of this engine if i continue occasionally driving
> (have to move the van twice a week to avoid parking tickets)? should
> i pull the spark plug and/or fuel injector power for that cylinder?
>
> the body on my van is pretty rusty and shot, so i'm not sure it's
> worth the effort and expense to install a new engine... how feasable
> is it to rebuild one in place? could i just throw in new bearings,
> piston rings and head gasket? or maybe just replace the one that blew?
> or is it likely that the cylinder is all tore up and needs to be
> bored?
>
> i'm planning to leave the country in the next year, so i really only
> need to get another dozen or so road trips out of my van before she
> retires... she's not used daily.
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